EL PASO ELECTRIC COMPANY (EPE)
FACILITIES STUDY FOR PROPOSED HVDC TERMINAL
INTERCONNECTION AT NEW ARTESIA 345 KV BUS
El Paso Electric Company
System Operations Department
System Planning Section
May 2004
TABLE OF CONTENTS
1.0
Executive Summary .......................................................................................Page
1
2.0
Introduction....................................................................................................Page
2.1 Performance Criteria................................................................................Page
2.1.1 Voltage Violation Criteria ..........................................................Page
2.1.2 Loading Violation Criteria .........................................................Page
5
6
7
7
3.0
Methodology ..................................................................................................Page 8
3.1 Assumptions..........................................................................................Page 8
3.2. Procedure ..............................................................................................Page 8
3.2.1 Base Case Development and Description of Cases....................Page 8
3.2.2 Powerflow Analysis ...................................................................Page 9
3.2.3 Delta Analysis ............................................................................Page 9
3.2.4 Q-V Analysis..............................................................................Page 10
3.2.5 Transient Stability Analysis .......................................................Page 10
4.0
Powerflow Analysis Results ..........................................................................Page 11
5.0
Delta V Analysis Results ...............................................................................Page 14
6.0
Q-V Analysis Results.....................................................................................Page
6.1 2008 Case 1...........................................................................................Page
6.2 2008 Case 2...........................................................................................Page
6.3 2008 Case 3...........................................................................................Page
6.4 2008 Case 4...........................................................................................Page
6.5 2013 Case 1...........................................................................................Page
6.6 2013 Case 2...........................................................................................Page
6.7 2013 Case 3...........................................................................................Page
6.8 2013 Case 4...........................................................................................Page
19
19
20
21
21
22
23
23
24
7.0
Transient Stability Analysis Results ..............................................................Page
7.1 2008 Case 1...........................................................................................Page
7.2 2008 Case 2...........................................................................................Page
7.3 2008 Case 3...........................................................................................Page
7.4 2008 Case 4...........................................................................................Page
7.5 2013 Case 1...........................................................................................Page
7.6 2013 Case 2...........................................................................................Page
7.7 2013 Case 3...........................................................................................Page
7.8 2013 Case 4...........................................................................................Page
26
26
27
28
28
29
30
31
32
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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May 2004
TABLE OF CONTENTS
8.0
Cost Estimates................................................................................................Page 33
9.0
Disclaimer ......................................................................................................Page 34
10.0
Certification ...................................................................................................Page 35
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Interconnection At New Artesia 345 kV Bus
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APPENDICIES
EPE’s FERC Form 715 Filing .............................................................................Appendix 1
Powerflow Maps – One-Line Diagrams ..............................................................Appendix 2
List of Contingencies ..........................................................................................Appendix 3
Contingency Powerflow Analyses Table Results ..............................................Appendix 4
Delta V Table Results .........................................................................................Appendix 5
Q-V Plots ............................................................................................................Appendix 6
Stability Plots .......................................................................................................Appendix 7
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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May 2004
1.0 EXECUTIVE SUMMARY
El Paso Electric Company’s Generation Division (EPEGD) submitted a request to
System Planning for a Facilities Study of a proposed new project for native load service.
The purpose of this Facility Study is to determine all impacts on the El Paso Electric
(EPE) system due to the interconnection of a new HVDC terminal with Southwestern
Public Service Company (SPS) at Artesia, New Mexico.
The proposed HVDC terminal will provide up to 200 MW of additional native load
service for EPE and will be located near the existing SPS HVDC terminal located in
Artesia, New Mexico. The Study analyzed the HVDC configuration as being paralleled
with the existing HVDC terminal. System Planning analyzed the proposed increase in
interconnection capacity assuming that a second Artesia to El Paso 345 kV transmission
line, in addition to the existing Artesia-Amrad 345 kV line, will be needed to
accommodate the new HVDC terminal. Two options were considered, a second line
from then new Artesia HVDC terminal to Amrad 345 kV Substation, or a new line from
the new Artesia terminal to Caliente 345 kV Substation. Based on lower costs and
greater system reliability, the Artesia-Caliente 345 kV line option was selected as the
option to analyze in this study.
System modifications to correct impacts to the EPE transmission system and estimated
costs of these modifications were recommended in this Study. As requested by EPEGD,
the proposed HVDC terminal will deliver up to 200 MW of power into the EPE system in
addition to the power already being delivered by the existing HVDC terminal at Artesia
Substation. The proposed HVDC terminal was modeled as a resource for serving native
load. This study analyzed 2008 and 2013 Heavy Summer (HS) and Light Winter (LW)
base case scenarios. In the 2013 scenarios, the Rio Grande (RG) 6 and 7 generating units
were modeled as having been retired and replaced by a new EPE owned Newman 5
generation unit. Each case was studied using the reliability criteria and methodologies
described in subsequent sections of this report.
This Study included power flow, Q-V reactive margin, delta-V, and transient stability
analyses. Four cases representing the 2008 and 2013 HS and LW seasons were modeled.
Descriptions of these cases are listed below:
Case 1:
Case with the proposed HVDC terminal modeled to provide 50 MW of
power into EPE’s system.
Case 2:
Case with the proposed HVDC terminal modeled to provide 100 MW of
power into EPE’s system.
Case 3:
Case with the proposed HVDC terminal modeled to provide 150 MW of
power into EPE’s system.
Case 4:
Case with the proposed HVDC terminal modeled to provide 200 MW of
power into EPE’s system.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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Sensitivity powerflow analyses were performed on the 2008 HS cases described above.
These sensitivities analyzed single contingency conditions under two different HVDC
terminal interconnection configurations, one with the new HVDC terminal operating
separately to the existing HVDC terminal and the other with the new HVDC terminal tied
to the existing HVDC terminal. These analyses were performed to determine whether the
two HVDC terminals (new and existing) should be tied together or operated
independently of each other for system reliability reasons. The concern of tying the two
terminals together was whether the EPE underlying transmission system could handle up
to 400 MW of power flow in the event that either of the two lines coming out of Artesia
(Amrad-Artesia 345 kV line or the new Artesia-Caliente 345 kV line) and their
interconnections to the EPE system were lost due to a single contingency situation.
These analyses determined that the underlying transmission system can handle the
increased power flow in the event of an outage of either of the 345kv lines with no
criteria violations. It was determined that tying the two terminals together will provide
the best scenario for providing the greatest reliability to the system. Therefore, all
subsequent cases were analyzed using the configuration with the two HVDC terminals
tied together.
System Impact Estimated Costs
Utilizing study results and engineering judgment, proposed system modifications to
correct the criteria violations found in the analyses and estimated costs for those proposed
modifications are included in this Study. Further analyses of the system with the
recommended modifications installed were performed to insure that these modifications
will relieve all reliability criteria violations found in the analyses.
Results of the analyses show that two criteria violations occur on the existing EPE system
when the proposed HVDC terminal is interconnected into the EPE system. Power flow
analyses revealed overloading violations of the Arroyo and Caliente 345/115 kV
transformers due to the interconnection of the proposed project. The Caliente
autotransformer overload occurs during single contingency outage conditions in all cases
modeling the proposed project in the 2008 HS scenarios. The Arroyo autotransformer
overload occurs in all cases where the proposed project is delivering 100 MW or more
(Cases 2-4) to the EPE system in the 2008 HS scenarios. The estimated costs of these
two system modifications are shown below:
SYSTEM MODIFICATIONS AND ESTIMATED COSTS FOR
PROPOSED HVDC TERMINAL
SYSTEM MODIFICATION *
YEAR
Add 2nd Arroyo 200 MVA 115/345 kV autotransformer.
Add 3rd Caliente 200 MVA 115/345 kV autotransformer.
TOTAL COSTS
2008
2008
*
ESTIMATED
COST (2004$)
$2,710,050
$2,710,050
$5,420,100
Estimates include all material (i.e. breakers, switchgear, relays, etc.) necessary for the
installation as well as labor required for installation.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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May 2004
Caliente-Artesia2 345 kV Line Estimated Costs
In addition to the cost estimates shown above, the cost to build the new 345 kV
transmission line from the new HVDC terminal (Artesia2) to Caliente 345 kV Substation,
the cost to install the 50 MVAR line reactors on each end of the new line required for line
switching, and the cost for any associated substation work needed to connect the line are
also included in this Study. The cost for these system improvements are estimated to be
as follows:
Caliente Substation
In order to connect the new line from the proposed Artesia2 Sub, it will be
necessary to build a new 345kV bay, and connect it to the 345 kV ring bus. To do
this, one 345kV breaker and one 345kV disconnect switch into the ring bus will
be needed. This will create a new position for connecting the new line. A 345 kV
50 MVAR reactor will be connected to the line in parallel through a 345 kV
circuit breaker and a 345 kV disconnect switch. Since there is no room available
in the existing control house, it will be necessary to expand the control house at
least 18 ft, to accommodate seven relay racks, and an additional RTU. Land
acquisition, right of way and permits costs are not included. These substation
costs at Caliente are in addition to the estimated costs to install the third 345/115
kV autotransformer recommended above.
TOTAL
*
$2,772,000 *
Includes 50 MVAR reactor, bus work, breaker, disconnect switch, control
house expansion, relays, RTU, and labor necessary to connect the new line
into Caliente Substation
Artesia2 Substation
The configuration to connect the new line from Caliente sub will have three 345
kV breakers; one connecting the line to the new DC Tie, another will be the
reactor breaker and the third will be part of the partial ring bus. Each breaker will
have two sets of disconnect switches except the reactor breaker which will only
have one set. The line will have a 345 kV 50 MVAR reactor connected for line
switching. It is assumed that the relay racks will be in the control house where
the new DC Tie will be located. The cost for the DC Tie and its control house as
well as land acquisition, right of way and permits costs are not included in this
estimate.
TOTAL
*
$2,897,000 *
Includes 50 MVAR reactor, bus work, breakers, disconnect switches, relays,
and labor necessary to connect the new line into the new Artesia2
Substation.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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El Paso Electric Company
May 2004
170 mile 345 kV Transmission Line from Caliente-Artesia2
This estimate includes material (structures and conductor), labor, engineering,
surveying, inspection and permitting. Right of way and land acquisition are not
included.
TOTAL
$104,550,000
Therefore, the total estimated cost to construct the line (including modifications to
the substations to connect the line) is $110,219,000.
The total estimated costs of the project are show below:
System Impacts Cost
Caliente-Artesia2 345 kV line Cost
$5,420,100
$110,219,000
Estimated Total Project Cost
$115,639,100.
This study also assumes that the proposed HVDC terminal will be designed to include a
Static Var Compensating (SVC) device that regulates voltage levels in the area and
provides a 100% load factor correction at the new HVDC terminal (Artesia2). Delta-V,
Q-V, and Transient Stability analyses indicate that the transmission system will require
this SVC device to have a range of at least 50 capacitive (MVAC) and 130 reactive
(MVAR) to maintain voltage stability during single contingency or fault conditions.
More detailed studies will need to be performed in order to determine the exact size of
this device. Costs for the design and construction of the proposed terminal (including the
SVC) have not been included in this Study. However, a previous study performed in
April 1999 estimated costs to construct an HVDC terminal similar to the one being
studied here to be between $45 million and $50 million.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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El Paso Electric Company
May 2004
2.0 INTRODUCTION
This study was performed in response to a request for a Transmission and Facilities
Study by El Paso Electric Company’s Generation Division (EPEGD) to determine any
impacts on the El Paso Electric (EPE) system due to the interconnection of a new HVDC
terminal power resource to the EPE system. The proposed HVDC terminal will provide
up to 200 MW of power to EPE and will be located next to the existing SPS HVDC
terminal located in Artesia, New Mexico. EPEGD has requested that EPE T&D analyze
the proposed interconnection assuming that a new 345 kV transmission line from the
proposed HVDC terminal to EPE’s Caliente Substation will be built to import the power
into the EPE system. Modifications needed to correct impacts to the EPE system along
with estimated costs are provided in this Study.
As requested by EPEGD, the proposed HVDC terminal will deliver up to 200 MW of
power into the EPE system in addition to the power that is already being delivered by the
existing HVDC terminal at Artesia Substation. The proposed project was modeled as a
source for serving native load only. This Study analyzed power flow, Q-V reactive
margin, delta-V, and transient stability analyses. Four cases, representing 2008 and 2013
Heavy Summer (HS) and Light Winter (LW) seasons were modeled. Descriptions of the
cases studied are listed below:
Case 1:
Case with the proposed HVDC terminal modeled to provide 50 MW of
power into EPE’s system.
Case 2:
Case with the proposed HVDC terminal modeled to provide 100 MW of
power into EPE’s system.
Case 3:
Case with the proposed HVDC terminal modeled to provide 150 MW of
power into EPE’s system.
Case 4:
Case with the proposed HVDC terminal modeled to provide 200 MW of
power into EPE’s system.
Sensitivity powerflow analyses were performed on the 2008 HS cases described above.
These sensitivities analyzed single contingency conditions under two different HVDC
terminal interconnection configurations, one with the new HVDC terminal operating
separately to the existing HVDC terminal and the other with the new HVDC terminal tied
to the existing HVDC terminal. These analyses were performed to determine whether the
two HVDC terminals (new and existing) should be tied together or operated
independently of each other for system reliability reasons. The concern of tying the two
terminals together was whether either of the two lines coming out of Artesia (AmradArtesia 345 kV line or the new Artesia-Caliente 345 kV line) could handle up to 400 MW
of power flow in the event of the loss of the other 345 kV line. These analyses
determined that both lines could handle the increased power flow in the event that the
other line was lost with no criteria violations and that tying the two terminals together
will provide the best scenario for providing the greatest reliability to the system. This
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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El Paso Electric Company
May 2004
configuration also improves system reliability in the event of a Caliente-Amrad 345 kV
line outage. Therefore, all subsequent cases were analyzed using the configuration with
the two HVDC terminals tied together.
Given that the power imported from the proposed project will be modeled to serve EPE’s
native load, only impacts to EPE’s system were noted in this study. The evaluation
process in studying these impacts included powerflow, Delta V, Q-V reactive margin,
and transient stability analyses. All recommended modifications needed to correct the
impacts on the EPE system due to the proposed project and their corresponding estimated
costs were noted in this report.
It must also be noted that this study was not meant to analyze every scenario that may
occur on the EPE system. This study analyzed the boundaries around which the EPE
system can operate, under the scenarios agreed to by EPEGD and EPE T&D.
Results of the analyses indicate that two criteria violations will occur to the existing EPE
system when the proposed project is interconnected to the EPE transmission system.
Overload criteria violations were found on the Caliente and Arroyo 345/115 kV
autotransformers during single contingency conditions. Utilizing study results and
engineering judgment, proposed system modifications and estimated costs for these
modifications were made to correct these criteria violations. Further evaluation of the
system with the recommended modifications installed was performed to insure that the
recommended modifications will relieve all impacts observed in the scenarios analyzed.
2.1 Performance Criteria
The reliability criteria standards used by EPE in performing this study are readily
acceptable standards and are listed in Section 4 of EPE’s FERC Form 715 (Appendix 1).
This analysis was performed using the GE PSLF program. For pre-contingency
solutions, transformer tap phase-shifting transformer angle movement, static Var device
switching and area interchange control were allowed. For each contingency studied, all
regulating equipment (transformer controls and switched shunts) were fixed at precontingency positions. All buses, lines, and transformers in the El Paso control area with
base voltages of 69 kV and above were monitored.
Pre-contingency flows on EPE’s network elements must remain at or below the normal
rating of the element, and post-contingency flows on network elements must remain at or
below the emergency rating. Flows above 100% of an element’s rating are considered
overload criteria violations.
The minimum and maximum allowed voltages are specified in EPE’s latest FERC Form
715. Any voltage which did not meet criteria in the benchmark cases (without the
proposed HVDC terminal interconnection) was considered an exception to the criteria for
that specific bus and did not have a penalizing effect when evaluating the
interconnection.
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The criteria used in monitoring the EPE bus voltages are shown in Table 2-1.
Table 2.1: Voltage Performance Criteria.
Area
Conditions
Loading
Limit
Voltage
(p.u.)
Maximum
Volt. Drop
(∆V)
0.95 – 1.05
0.95 – 1.10
Normal
< Normal
Rating
0.95 – 1.08
0.90 – 1.05
EPE
Contingency
< Emergency
Rating
0.925 - 1.05
0.95 – 1.10
7%
0.95 – 1.08
7%
0.90 – 1.05
0.95 – 1.05
7%
Comments
69kV and above
Artesia 345 kV
Arroyo 345 kV PS
source side
Alamo, Sierra Blanca
and Van Horn 69kV
60 kV to 115 kV
Artesia 345kV
Arroyo 345kV PS
source side
Alamo, Sierra Blanca
and Van Horn 69kV
Hidalgo, Luna, or other
345 kV buses
It should be noted that the voltage drop criteria is specified as a percentage of the precontingency voltage. For example, if the pre-contingency voltage at a specific 345kV
bus is 1.030 pu, and the voltage drops to 0.9579 pu during the contingency, the voltage
drop would be 7%, calculated as:
∆V = ((Vpre-Vpost) ÷ Vpre) x 100% = ((1.030 – 0.9579) ÷ 1.030) x 100%
= (0.0721÷1.030) x 100% = 7.0%
2.1.1 Voltage Violation Criteria
The voltage criteria used in this study are shown in Table 2.1 above. In general, all bus
voltages 69 kV and above during All Lines In Service (ALIS) conditions must have per
unit voltages between 0.95 and 1.05 pu and between 0.925 and 1.05 pu during single
contingency (N-1) conditions. There are some exceptions to these criteria and are noted
in Table 2.1.
2.1.2 Loading Violation Criteria
The loading criteria used in this Study are based on WECC loading criteria. An element
(transmission line, transformer) cannot be loaded to over 100% of its continuous/normal
rating for an ALIS condition. During N-1 contingency conditions, the element many not
exceed 100 % of its emergency rating.
Facilities Study For Proposed HVDC Terminal
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3.0 METHODOLOGY
3.1
Assumptions
The following assumptions are consistent for all study scenarios unless otherwise
noted.
•
•
•
•
3.2
Project dollar amounts shown are in 2004 U.S. dollars. The cost of the
proposed project and associated equipment (i.e. HVDC terminal and associated
SVC) is separate and not included in this study.
This study assumes that EPE substation space is available for the system
recommended modifications.
The cost estimates provided here include material, labor, and overhead costs for
installing new equipment.
This study does not analyze any transmission service from the interconnection
point to any point on the grid. The study only determined modifications needed
to deliver the proposed HVDC terminal output to the interconnection point
(Caliente 345 kV Substation) for the purpose of serving native load.
Procedure
As previously mentioned, the analyses performed in this study include Powerflow,
Delta V, Q-V, and Transient Stability Analyses. Detailed discussions for each topic
have been included in this report (for quick reference of any topic, refer to the Table
of Contents). The following is a description of the procedures used to complete the
analyses.
3.2.1
Base Case Development and Description of Cases
Four cases, each representing the 2008 and 2013 Heavy Summer (HS) and
Light Winter (LW) seasons were modeled in these analyses. Descriptions of
the cases analyzed are listed below:
Case 1:
Case with the proposed HVDC terminal modeled to provide 50
MW of power into EPE’s system.
Case 2:
Case with the proposed HVDC terminal modeled to provide 100
MW of power into EPE’s system.
Case 3:
Case with the proposed HVDC terminal modeled to provide 150
MW of power into EPE’s system.
Case 4:
Case with the proposed HVDC terminal modeled to provide 200
MW of power into EPE’s system.
Facilities Study For Proposed HVDC Terminal
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Each of the cases described above was analyzed in the 2008 HS and 2013 HS
and LW seasons. In order to determine which impacts resulted from the
proposed HVDC terminal interconnection, each case was analyzed both with
and without the HVDC terminal representation. Power output levels of
between 50 MW and 200 MW were modeled for the HVDC terminal as
described in the description of cases above.
Base cases were developed for each case (Cases 1-4), simulating the system
with all lines in service and without the proposed HVDC terminal. Single
contingency powerflow analyses were then performed on these cases to
identify any existing system impacts without the proposed project. Voltage
and/or loading criteria violations in the EPE area were noted and corrected in
these cases.
The four “Base Cases” without the proposed HVDC terminal were then used
to develop cases which included the HVDC terminal at various power output
levels ranging from 50 Mw to 200 MW. Single contingency powerflow
analyses were then performed on these cases. The cases with the new HVDC
terminal were then compared against the cases without the new HVDC
terminal to determine the impacts due to the proposed interconnection project.
3.2.2 Powerflow Analysis
Once the base cases were developed for each of the 2008 and 2013 HS and
LW seasons, powerflow single contingency analyses were performed. The
same contingencies were evaluated for all cases and are identified in
Appendix 3. Based on engineering judgment, these contingencies were
selected because they are the ones most likely to stress the EPE system.
Contingencies in the areas of neighboring utilities were not analyzed because
the proposed generation will be used to serve native load and thus should only
affect the EPE area. Contingency powerflow analyses table results can be
found in Appendix 4.
3.2.3 Delta V Analysis
Delta V (∆V) studies were performed with the proposed HVDC terminal
interconnection modeled. Pre-contingency and post-contingency voltages
were measured at various EPE 345 kV buses to determine if the voltage drop
or ∆V from a pre–contingency to a post-contingency condition did not violate
the EPE voltage criteria as described in Table 2.1 shown in Section 2.1 of this
report. The ∆V is calculated using the following equation:
∆V = (Vpre-Vpost) / Vpre x 100%
Tables listing the ∆V analyses for all the cases can be found in Appendix 5.
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May 2004
3.2.4
Q-V Analysis
Q-V analyses were performed on the 2008 and 2013 HS and LW cases to
verify that the WSCC criteria for reactive power margin will be met under the
worst contingencies on the EPE system. A procedure developed by WECC
was used to determine the reactive power margin. As outlined in this
procedure, EPE’s load was increased by 5% and the worst contingency was
analyzed to determine the reactive margin on the system. The margin is
determined by identifying the critical (weakest) bus on the system during the
worst contingency. The critical bus is the most reactive deficient bus. Q-V
curves are developed and the minimum point on the curve is defined as the
critical point. If the critical point of the Q-V curve is positive, the system is
reactive power deficient. If it is negative, then the system has sufficient
reactive power margin and meets the WSCC criteria.
Prior experience has shown that the worst contingencies impacting reactive
power margin are the Springerville-Luna, Luna-Diablo, and Greenlee-Hidalgo
345 kV lines and the buses most impacted are the 345 kV buses at Arroyo,
Newman, Caliente, Diablo, Luna, and Hidalgo. However, for this study, three
other contingencies were analyzed in the area of the proposed project to
determine the worst contingency. Q-V analyses were performed for the 2008
HS and 2008 LW Case 1 scenarios for outages of the Caliente-Artesia2
(proposed line), Artesia-Amrad, and Amrad-Artesia 345 kV lines. These
analyses determined that the Caliente2-Artesia 345 kV line contingency was
the worst contingency. Therefore, this contingency was used to evaluate
reactive power margins for all the remaining cases. Q-V plots were created
showing the margins available at the Arroyo 345 kV, Caliente 345 kV, Diablo
345 kV, Luna 345 kV, and Newman 345 kV buses. Plots showing the results
of the Q-V analyses can be found in Appendix 6.
3.2.5
Transient Stability Analysis
The stability data representation for the EPEGD proposed HVDC terminal and
corresponding SVC device were based on data found in the WECC stability
data base. The SPS Blackwater HVDC terminal data was used as an
approximation to simulate the proposed HVDC terminal and the SVC device.
EPE used these generic equivalent models for the HVDC terminal and SVC
device components. Since the specific devices that will be used for this
proposed HVDC terminal have not been determined yet, these generic models
were used as the best data available to complete the study. The models were
then represented in the WECC master stability file (dated 3/16/04) for use in
the GE Transient Stability Program. Transient stability analyses were
conducted on all 2008 and 2013 HS and LW cases. Plots showing the results
of the Transient Stability analyses can be found in Appendix 7.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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El Paso Electric Company
May 2004
4.0
POWER FLOW ANALYSIS RESULTS
The four cases described in section 3.2.1 of this report were developed for use in this
analysis. Each of the four cases was developed to represent the 2008 and 2013 Heavy
Summer (HS) and Light Winter (LW) seasons. These cases represent four scenarios in
which the EPE system may operate with the interconnection of the proposed HVDC
terminal at various output levels.
The table below shows transmission loadings with the proposed HVDC terminal
interconnection for the 2008 HS cases. Once the overloads were corrected in the 2008
HS cases, no other overloads were found in the 2008 LW, 2013 HS, or 2013 LW cases.
2008 HS TRANSMISSION FACILITY OVERLOADS
CASE
#
1
CONTINGENCY
Caliente 115/345 kV transformer #1
OVERLOADED ELEMENT
Caliente 115/345 kV transformer #2
PERCENT
LOADING *
106.8
2
Caliente 115/345 kV transformer #1
Caliente 115/345 kV transformer #2
112.8
Luna-Diablo 345 kV line
Arroyo 115/345 kV transformer
100.4
Anthony-Newman 115 kV line
Arroyo 115/345 kV transformer
101.7
Amrad 115/345 kV transformer
Arroyo 115/345 kV transformer
100.4
3
Caliente 115/345 kV transformer #1
Luna-Diablo 345 kV line
Anthony-Newman 115 kV line
Amrad 115/345 kV transformer
Caliente 115/345 kV transformer #2
Arroyo 115/345 kV transformer
Arroyo 115/345 kV transformer
Arroyo 115/345 kV transformer
117.3
102.0
102.1
102.3
4
Caliente 115/345 kV transformer #1
Caliente 115/345 kV transformer #2
Luna-Diablo 345 kV line
Arroyo 115/345 kV transformer
Anthony-Newman 115 kV line
Arroyo 115/345 kV transformer
Amrad 115/345 kV transformer
Arroyo 115/345 kV transformer
* Percent loadings are based on the element’s emergency rating.
121.9
103.7
102.7
104.3
Notes:
As can be seen from the tables above, one of the Caliente autotransformers experiences a
criteria violation during an outage of the second Caliente autotransformer and the Arroyo
autotransformer experiences criteria violations during each of three single contingency
conditions. Therefore, the following system modifications are recommended in order to
eliminate these criteria violations:
1. Add 2nd Arroyo 115/345 kV auto transformer in 2008
2. Add 3rd Caliente 115/345 kV auto transformer in 2008
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
11
El Paso Electric Company
May 2004
Making these system improvements eliminates the criteria violations shown above for all
other cases (2008 LW, 2013 HS, and 2013 LW) in this study. No other criteria violations
were found in any of the other cases after these modifications were made.
Please note that these analyses assume that the proposed HVDC terminal will be
interconnected to the EPE system through a new 345 kV line from the new HVDC
terminal at Artesia to EPE’s Caliente 345 kV Substation. As such, the new line, the
associated modifications needed to connect this line to the substations (Caliente and
Artesia2), and the line reactors required for line switching, must be included as part of the
system improvements to allow the interconnection of the proposed HVDC terminal and
the importation of up to 200 MW of additional power into the EPE transmission system.
These analyses also assume that the proposed HVDC terminal is tied together with the
existing HVDC terminal as described in Section 2.0 above.
Below are tables which show the flows and percent loadings of elements in the AmradArtesia area during single contingency outages of the new Caliente-Artesia and the
existing Caliente-Amrad 345 kV lines in the 2008 HS and 2013HS Case 4 scenarios with
the above system modifications included.
2008 HS CASE 4 ELEMENT LOADINGS
DURING CALIENTE-ARTESIA 345 KV LINE OUTAGE
ELEMENT
FLOW (MVA)
% LOADING
Amrad-Artesia 345 kV line
398.2
45.4
Amrad 345/115 kV autotransformer
148.2
63.6
Caliente-Amrad 345 kV line
248.2
28.5
Caliente 345/115 kV autotransformer(s)
114.3
57.9
2008 HS CASE 4 ELEMENT LOADINGS
DURING AMRAD-ARTESIA 345 KV LINE OUTAGE
ELEMENT
FLOW (MVA)
% LOADING
Caliente-Artesia2 345 kV line
400.8
50.7
Amrad 345/115 kV autotransformer
105.4
45.3
Caliente-Amrad 345 kV line
107.9
14.6
Caliente 345/115 kV autotransformer(s)
114.2
57.8
2013 HS CASE 4 ELEMENT LOADINGS
DURING CALIENTE-ARTESIA 345 KV LINE OUTAGE
ELEMENT
FLOW (MVA)
% LOADING
Amrad-Artesia 345 kV line
400.6
45.7
Amrad 345/115 kV autotransformer
139.8
60.0
Caliente-Amrad 345 kV line
258.6
29.5
Caliente 345/115 kV autotransformer(s)
104.4
52.7
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
12
El Paso Electric Company
May 2004
2013 HS CASE 4 ELEMENT LOADINGS
DURING AMRAD-ARTESIA 345 KV LINE OUTAGE
ELEMENT
FLOW (MVA)
% LOADING
Caliente-Artesia2 345 kV line
398.4
49.7
Amrad 345/115 kV autotransformer
102.5
44.1
Caliente-Amrad 345 kV line
104.5
14.0
Caliente 345/115 kV autotransformer(s)
107.7
54.3
As can be seen from the tables above, there are no additional criteria violations during
outages of the new Caliente-Artesia 345 kV line or the Amrad-Artesia 345 kV line when
the system improvements recommended above are made. Additionally, no voltage
criteria violations were found during these contingencies because the Static Var
Compensating (SVC) device located at the proposed HVDC terminal provides adequate
VAR support during the contingencies. Therefore, the EPE system can handle an outage
of the proposed Caliente-Artesia 345 kV line without the need for any additional system
improvements other than the ones listed above.
It should be noted that the costs associated with the design and construction of the new HVDC
terminal have not been included in this study. The study assumes that the proposed HVDC
terminal will be designed to include an SVC device to regulate voltage levels in the area.
Delta-V, Q-V, and Transient Stability analyses indicate that the transmission system will
require this SVC device to have a range of at least 50 capacitive (MVAC) and 130
reactive (MVAR) to maintain voltage stability during single contingency conditions.
However, more detailed analyses will need to be performed in order to determine the
exact size of this device. The study also assumes that the new terminal will be designed
to provide 100% load factor correction.
Please refer to Appendix 2 for the powerflow maps of these analyses and to Appendix 4
for the tables showing the criteria violations found during these contingency analyses.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
13
El Paso Electric Company
May 2004
5.0
DELTA V ANALYSIS RESULTS
A delta V (∆V) analysis was performed on all 2008 and 2013 HS and LW cases with the
proposed HVDC terminal interconnection modeled. Pre-contingency and postcontingency voltages were measured at various EPE 345 kV buses to determine if the
voltage drop or ∆V from a pre–contingency to a post-contingency condition does not
violate the EPE voltage criteria as described in Table 2.1 shown in Section 2.1 of this
report. The ∆V is calculated using the following equation:
∆V = (Vpre-Vpost) / Vpre
∆V analyses were performed for single contingencies of the three 345 kV lines that will
cause the greatest impact with the proposed project on the EPE system. The analyses
were performed on the Caliente-Artesia2, Caliente-Amrad, and Amrad-Artesia 345 kV
lines. The tables below show the results of the analyses with the greatest ∆V for some of
the 345 kV and 115 kV buses in the area.
2008 HS CASE 1 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.032
1.039
1.031
1.021
1.019
CAL-ART2
OUTAGE
V (PU)
1.009
1.016
1.009
0.999
0.996
∆V
(PU)
2.23
2.21
2.07
2.21
2.29
CAL-AMRAD
OUTAGE
V (PU)
1.019
1.038
1.020
1.012
1.007
∆V
(PU)
1.26
0.10
1.06
0.95
1.17
AMRAD-ART
OUTAGE
V (PU)
1.032
1.033
1.030
1.019
1.018
∆V
(PU)
0.00
0.58
0.12
0.20
0.13
2008 HS CASE 2 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.031
1.038
1.030
1.020
1.018
CAL-ART2
OUTAGE
V (PU)
0.996
1.008
0.998
0.988
0.984
∆V
(PU)
3.39
2.89
3.03
3.16
3.36
CAL-AMRAD
OUTAGE
V (PU)
1.018
1.037
1.019
1.010
1.006
∆V
(PU)
1.26
0.10
1.02
0.95
1.13
AMRAD-ART
OUTAGE
V (PU)
1.031
1.028
1.028
1.017
1.016
∆V
(PU)
0.00
0.96
0.15
0.26
0.16
∆V
(PU)
1.17
0.19
0.98
0.97
1.09
AMRAD-ART
OUTAGE
V (PU)
1.029
1.021
1.026
1.014
1.014
∆V
(PU)
0.00
1.45
0.18
0.38
0.21
2008 HS CASE 3 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.029
1.036
1.028
1.018
1.016
CAL-ART2
OUTAGE
V (PU)
1.005
1.011
1.005
0.994
0.991
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
∆V
(PU)
2.33
2.41
2.17
2.38
2.40
14
CAL-AMRAD
OUTAGE
V (PU)
1.017
1.034
1.018
1.008
1.005
El Paso Electric Company
May 2004
2008 HS CASE 4 ∆V ANALYSIS
BUS
AMRAD
CALIENTE
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.027
1.034
1.026
1.016
1.014
CAL-ART2
OUTAGE
V (PU)
0.979
0.994
0.983
0.972
0.967
∆V
(PU)
4.67
3.87
4.17
4.38
4.63
CAL-AMRAD
OUTAGE
V (PU)
1.015
1.031
1.016
1.006
1.003
∆V
(PU)
1.17
0.29
0.98
1.01
1.08
AMRAD-ART
OUTAGE
V (PU)
1.011
1.002
1.013
1.001
1.000
∆V
(PU)
1.56
3.09
1.29
1.47
1.42
∆V
(PU)
0.62
0.14
0.49
0.45
0.51
AMRAD-ART
OUTAGE
V (PU)
1.035
1.035
1.039
1.036
1.054
∆V
(PU)
0.00
0.64
0.12
0.22
0.12
∆V
(PU)
0.57
-0.97
0.33
0.14
0.34
AMRAD-ART
OUTAGE
V (PU)
1.035
1.028
1.039
1.035
1.054
∆V
(PU)
0.00
1.01
0.16
0.32
0.17
∆V
(PU)
0.54
-1.01
0.33
0.14
0.34
AMRAD-ART
OUTAGE
V (PU)
1.034
1.024
1.039
1.035
1.054
∆V*
(PU)
0.00
1.39
0.16
0.32
0.17
2008 LW CASE 1 ∆V ANALYSIS
BUS
AMRAD
CALIENTE
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.035
1.041
1.041
1.038
1.055
CAL-ART2
OUTAGE
V (PU)
1.021
1.023
1.027
1.023
1.041
∆V
(PU)
1.44
1.85
1.29
1.43
1.35
CAL-AMRAD
OUTAGE
V (PU)
1.029
1.040
1.036
1.050
1.003
2008 LW CASE 2 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.035
1.038
1.041
1.038
1.055
CAL-ART2
OUTAGE V
(PU)
0.996
1.004
1.005
1.002
1.018
∆V
(PU)
3.87
3.43
3.40
3.51
3.55
CAL-AMRAD
OUTAGE
V (PU)
1.029
1.048
1.037
1.036
1.052
2008 LW CASE 3 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.034
1.038
1.040
1.037
1.054
CAL-ART2
OUTAGE
V (PU)
1.010
1.013
1.017
1.014
1.018
∆V
(PU)
2.33
2.43*
2.15
2.29
2.05
CAL-AMRAD
OUTAGE
V (PU)
1.028
1.048
1.037
1.036
1.052
* The ∆V at the Caliente 345 kV bus was above the 7% limit. This was corrected by
increasing the range on the capacitive side of the proposed SVC at the HVDC terminal
from 0 MVAC to 25 MVAC.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
15
El Paso Electric Company
May 2004
2008 LW CASE 4 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.033
1.037
1.039
1.037
1.054
CAL-ART2
OUTAGE
V (PU)
0.989
1.000
0.998
0.995
1.010
∆V *
(PU)
4.33
3.67
3.95
4.06
4.13
CAL-AMRAD
OUTAGE
V (PU)
1.027
1.047
1.037
1.036
1.052
∆V *
(PU)
0.57
-0.98
0.33
0.14
0.34
AMRAD-ART
OUTAGE
V (PU)
1.033
1.023
1.039
1.035
1.054
∆V *
(PU)
0.00
1.36
0.16
0.32
0.17
* The analysis of the ∆V for this case assumes the same SVC range used in the 2008 LW
Case 3 scenario.
2013 HS CASE 1 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.032
1.038
1.030
1.018
1.034
CAL-ART2
OUTAGE
V (PU)
1.007
1.014
1.008
0.994
1.009
∆V
(PU)
2.40
2.32
2.18
2.36
2.43
CAL-AMRAD
OUTAGE
V (PU)
1.020
1.036
1.020
1.009
1.023
∆V
(PU)
1.12
0.15
0.94
0.87
1.05
AMRAD-ART
OUTAGE
V (PU)
1.032
1.031
1.029
1.016
1.032
∆V
(PU)
0.00
0.67
0.13
0.23
0.15
∆V
(PU)
1.26
0.13
0.98
0.92
1.10
AMRAD-ART
OUTAGE
V (PU)
1.031
1.030
1.029
1.016
1.033
∆V
(PU)
0.00
0.89
0.15
0.27
0.16
∆V
(PU)
1.27
0.13
1.05
1.01
1.15
AMRAD-ART
OUTAGE
V (PU)
1.032
1.027
1.029
1.016
1.033
∆V
(PU)
0.00
1.20
0.18
0.35
0.19
2013 HS CASE 2 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.031
1.039
1.031
1.019
1.035
CAL-ART2
OUTAGE
V (PU)
0.996
1.011
1.002
0.989
1.002
∆V
(PU)
3.39
2.69
2.80
2.98
3.12
CAL-AMRAD
OUTAGE
V (PU)
1.018
1.037
1.021
1.010
1.023
2013 HS CASE 3 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.032
1.039
1.031
1.020
1.035
CAL-ART2
OUTAGE
V (PU)
0.989
1.006
0.991
0.978
0.990
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
∆V
(PU)
4.13
3.20
3.93
4.12
4.37
16
CAL-AMRAD
OUTAGE
V (PU)
1.019
1.038
1.020
1.009
1.023
El Paso Electric Company
May 2004
2013 HS CASE 4 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.031
1.040
1.031
1.020
1.035
CAL-ART2
OUTAGE
V (PU)
0.965
0.992
0.972
0.959
0.969
∆V
(PU)
6.41
4.57
5.77
5.99
6.43
CAL-AMRAD
OUTAGE
V (PU)
1.018
1.038
1.020
1.009
1.022
∆V
(PU)
1.34
0.13
1.10
1.11
1.23
AMRAD-ART
OUTAGE
V (PU)
1.030
1.022
1.028
1.015
1.032
∆V
(PU)
0.11
1.71
0.28
0.52
0.32
∆V
(PU)
1.08
0.29
0.93
0.88
0.98
AMRAD-ART
OUTAGE
V (PU)
1.031
1.029
1.030
1.022
1.008
∆V
(PU)
0.00
0.79
0.14
0.27
0.15
∆V
(PU)
1.13
0.24
0.93
0.88
0.98
AMRAD-ART
OUTAGE
V (PU)
1.031
1.027
1.030
1.022
1.008
∆V
(PU)
0.00
1.04
0.16
0.34
0.18
2013 LW CASE 1 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.031
1.037
1.031
1.024
1.009
CAL-ART2
OUTAGE
V (PU)
0.996
1.004
0.998
0.990
0.975
∆V
(PU)
3.53
3.29
3.19
3.39
3.36
CAL-AMRAD
OUTAGE
V (PU)
1.021
1.034
1.022
1.016
1.000
2013 LW CASE 2 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
1.031
1.037
1.031
1.025
1.010
CAL-ART2
OUTAGE
V (PU)
0.987
0.999
0.990
0.982
0.967
∆V
(PU)
4.47
3.85
4.01
4.21
4.22
CAL-AMRAD
OUTAGE
V (PU)
1.020
1.035
1.022
1.016
1.000
2013 LW CASE 3 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
CAL-ART2
OUTAGE V
(PU)
∆V
(PU)
CAL-AMRAD
OUTAGE
V (PU)
∆V
(PU)
AMRAD-ART
OUTAGE
V (PU)
∆V
(PU)
1.031
1.038
1.017
1.019
1.45
1.89*
1.019
1.036
1.22
0.24
1.019
1.036
1.22
0.24
1.031
1.025
1.010
1.018
1.010
0.995
1.39
1.58
1.47
1.022
1.016
1.000
0.93
0.88
0.98
1.030
1.022
1.008
0.16
0.34
0.18
* The ∆V at the Caliente 345 kV bus was above the 7% limit. This was corrected by
increasing the range on the capacitive side of the proposed SVC at the HVDC terminal
from 0 MVAC to 50 MVAC.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
17
El Paso Electric Company
May 2004
2013 LW CASE 4 ∆V ANALYSIS
BUS
AMRAD 345
CALIENTE 345
AMRAD 115
ALAMOTAP 115
HOLLOMAN 115
BASE
VOLT
(PU)
CAL-ART2
OUTAGE V
(PU)
∆V *
(PU)
CAL-AMRAD
OUTAGE
V (PU)
∆V *
(PU)
AMRAD-ART
OUTAGE
V (PU)
∆V *
(PU)
1.031
1.039
1.014
1.018
1.70
2.02
1.018
1.036
1.29
0.26
1.031
1.026
0.00
1.21
1.032
1.027
1.010
1.018
1.010
0.995
1.62
1.82
1.70
1.021
1.016
0.999
1.06
1.05
1.11
1.030
1.025
1.009
0.14
0.22
0.14
* The analysis of the ∆V for this case assumes the same SVC range used in the 20013
LW Case 3 scenario.
As stated in EPE’s FERC Form 715 Transmission Planning Reliability Criteria,
(Appendix 1) EPE’s post disturbance post-transient voltage drop (∆V) must not exceed
7% at the Hidalgo 345 kV, Luna 345 kV, or any EPE 345 kV buses.
Results of these analyses indicate that the ∆V criteria violations experienced in the 2008
and 2013 LW Case 3 and Case 4 scenarios can be corrected by increasing the capacitive
range of the SVC device. These analyses determined that the SVC device required as
part of the HVDC terminal design will need to have a range of at least 25 MVAC to 130
MVAR in 2008 and 50 MVAC to 130 MVAR in 2013. Again, more detailed analyses
will have to be performed in order to determine the exact size of this SVC device.
Please refer to Appendix 5 for the tables showing the results of the ∆V analyses.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
18
El Paso Electric Company
May 2004
6.0
Q-V ANALYSIS RESULTS
Q-V analyses are conducted in order to verify that the scenarios, which include the
interconnection of the proposed HVDC terminal, comply with the WECC Voltage
Stability Criteria. Q-V analysis provides a way to investigate the potential for voltage
collapse during the post-transient period within 3 minutes after the disturbance. Q-V
analyses were performed for all cases in this Study.
A procedure developed by WECC is used to determine the reactive power margin. As
outlined in this procedure, load is increased by 5% and the worst contingency is analyzed
to determine the reactive margin on the system. The margin is determined by identifying
the critical (weakest) bus on the system during the worst contingency. The critical bus is
the most reactive deficient bus. Q-V curves are developed and the minimum point on the
curve is the critical point. If the minimum point of the Q-V curve is positive, i.e., above
the x-axis, the system is reactive power deficient. If it is negative, i.e., below the x-axis,
then the system has some reactive power margin and meets the WECC criteria.
From experience, it has been established that the worst contingency impacting reactive
power margin on the EPE system is the Luna-Diablo (LD) 345 kV line. However, for
this study, three additional contingencies were analyzed in the vicinity of the proposed
project to determine if any of them would cause more of an impact than the LD outage.
Q-V analyses were performed on the 2008 HS and 2008 LW Case 1 scenarios for an
outage of the Caliente-Artesia2 (proposed line), Artesia-Amrad, and Amrad-Artesia 345
kV lines. These analyses determined that the Caliente2-Artesia 345 kV line contingency
was the worst contingency which impacted the reactive power margin. Therefore, this
contingency was used to evaluate reactive power margins for all the remaining cases to
verify that EPE reactive power margins are in compliance with the WECC criteria. Q-V
analyses were conducted for the 2008 and 2013 HS and LW system load configurations.
EPE 345 kV buses monitored included Arroyo, Caliente, Diablo, Luna, and Newman 345
kV buses. EPE 115 kV buses monitored included the Amrad, Holloman, White Sands,
Caliente, and Alamogordo 115 kV buses. Resulting plots and reactive power margins of
the analyses can be found in Appendix 6.
Following are the results of the Q-V analysis. The tables that follow show the reactive
power margins available and the most critical bus in each case. Please note that a
negative number indicates that there is sufficient reactive power to meet WSCC criteria
and a positive number indicates that the system is deficient in reactive power and does
not meet the criteria.
6.1 2008 Case 1
The 2008 HS and LW Case 1 scenarios simulated the existing EPE system with the
proposed HVDC terminal interconnection. As outlined in the WECC procedure for
determining reactive power margin, EPE’s load was increased by 5% and the worst
contingency was analyzed. The margin was determined by identifying the critical
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
19
El Paso Electric Company
May 2004
(weakest) bus on the system during the worst contingency. This case was modeled
with the HVDC terminal output at 50 MW.
The following table shows the results of the 2008 HS and LW Case 1 analyses.
Available reactive margins for the critical buses on both the 345 kV and 115 kV
systems during a Caliente-Artesia2 (CA) 345 kV line contingency are shown below.
2008 Case 1 – Available Reactive Margin during CA 345 kV Outage
System Condition
MVAR Margin
Critical Bus
2008 HS 345 kV
-162.3
Caliente 345 kV
2008 HS 115 kV
-19.8
Holloman 115 kV
2008 LW 345 kV
-144.5
Caliente 345 kV
2008 LW 115 kV
-16.3
Amrad 115 kV
As can be seen in the above table, there were no reactive power margin deficiencies
in either of the two 2008 Case 1 scenarios analyzed. The 345 kV Q-V reactive
power margin plots for the 2008 HS and LW Case 1 scenarios can be found on
pages 1-2 and the 115 kV Q-V reactive power margin plots for these scenarios can
be found on pages 18-19 of Appendix 6.
6.2 2008 Case 2
The 2008 HS and LW Case 2 scenarios simulated the existing EPE system with the
proposed HVDC terminal interconnection. As outlined in the WECC procedure for
determining reactive power margin, load was increased by 5% and the worst
contingency was analyzed. The margin was determined by identifying the critical
(weakest) bus on the system during the worst contingency. This case was modeled
with the HVDC terminal output at 100 MW.
The following table shows the results of the 2008 HS and LW Case 2 analyses.
Available reactive margins for the critical buses on both the 345 kV and 115 kV
systems during a CA 345 kV line contingency are shown below.
2008 Case 2 – Available Reactive Margin during CA 345 kV Outage
System Condition
MVAR Margin
Critical Bus
2008 HS 345 kV
-130.9
Caliente 345 kV
2008 HS 115 kV
-16.8
Holloman 115 kV
2008 LW 345 kV
-105.6
Caliente 345 kV
2008 LW 115 kV
-15.0
Holloman 115 kV
As can be seen in the above table, there were no reactive power margin deficiencies
in either of the two 2008 Case 2 scenarios analyzed. The 345 kV Q-V reactive
power margin plots for 2008 HS and LW Case 2 scenarios can be found on pages 34 and the 115 kV Q-V reactive power margin plots for these scenarios can be found
on pages 20-21 of Appendix 6.
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May 2004
6.3 2008 Case 3
The 2008 HS and LW Case 3 scenarios simulated the existing EPE system with the
proposed HVDC terminal interconnection. As outlined in the WECC procedure for
determining reactive power margin, load was increased by 5% and the worst
contingency was analyzed. The margin was determined by identifying the critical
(weakest) bus on the system during the worst contingency. This case was modeled
with the HVDC terminal output at 150 MW.
The following table shows the results of the 2008 HS and LW Case 3 analyses.
Available reactive margins for the critical buses on both the 345 kV and 115 kV
systems during a CA 345 kV line contingency are shown below.
2008 Case 3 – Available Reactive Margin during CA 345 kV Outage
System Condition
MVAR Margin
Critical Bus
2008 HS 345 kV
-93.8
Caliente 345 kV
2008 HS 115 kV
-19.7
Holloman 115 kV
2008 LW 345 kV
-74.1
Caliente 345 kV
2008 LW 115 kV
-23.2
Holloman 115 kV
As can be seen in the above table, there were no reactive power margin deficiencies
in either of the two 2008 Case 3 scenarios analyzed. The 345 kV Q-V reactive
power margin plots for 2008 HS and LW Case 2 scenarios can be found on pages 56 and the 115 kV Q-V reactive power margin plots for these scenarios can be found
on pages 22-23 of Appendix 6.
6.4 2008 Case 4
The 2008 HS and LW Case 4 scenarios simulated the existing EPE system with the
proposed HVDC terminal interconnection. As outlined in the WECC procedure for
determining reactive power margin, load was increased by 5% and the worst
contingency was analyzed. The margin was determined by identifying the critical
(weakest) bus on the system during the worst contingency. This case was modeled
with the HVDC terminal output at 200 MW.
The following table shows the results of the 2008 HS and LW Case 4 analyses.
Available reactive margins for the critical buses on both the 345 kV and 115 kV
systems during a CA 345 kV line contingency are shown below.
2008 Case 4 – Available Reactive Margin during CA 345 kV Outage
System Condition
MVAR Margin
Critical Bus
2008 HS 345 kV
-45.5
Caliente 345 kV
2008 HS 115 kV
-12.5
Holloman 115 kV
2008 LW 345 kV
-68.8
Caliente 345 kV
2008 LW 115 kV
-13.2
Holloman 115 kV
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May 2004
As can be seen in the above table, there were no reactive power margin deficiencies
in either of the two 2008 Case 4 scenarios analyzed. The Q-V margin determined
in the 2008 LW Case 4 scenario assumed that the SVC device at the proposed
HVDC terminal will have a range of 25 MVAC to 130 MVAR. The 2008 HS Case
4 scenario margin was determined based on an SVC range of 0 MVAC to 130
MVAR. As stated previously, more detailed studies will be needed in order to
determine the exact size of the SVC device. The 345 kV Q-V reactive power
margin plots for 2008 HS and LW Case 2 scenarios can be found on pages 7-8 and
the 115 kV Q-V reactive power margin plots for these scenarios can be found on
pages 24-25 of Appendix 6.
6.5 2013 Case 1
The 2013 HS and LW Case 1 scenarios simulated the existing EPE system with the
proposed HVDC terminal interconnection. As outlined in the WECC procedure for
determining reactive power margin, load was increased by 5% and the worst
contingency was analyzed. The margin was determined by identifying the critical
(weakest) bus on the system during the worst contingency. This case modeled a
2013 load pattern and the HVDC terminal output at 50 MW.
The following table shows the results of the 2013 HS and LW Case 1 analyses.
Available reactive margins for the critical buses on both the 345 kV and 115 kV
systems during a CA 345 kV line contingency are shown below.
2013 Case 1 – Available Reactive Margin during CA 345 kV Outage
System Condition
MVAR Margin
Critical Bus
2013 HS 345 kV
-179.1
Caliente 345 kV
2013 HS 115 kV
-18.8
Holloman 115 kV
2013 LW 345 kV
-43.1
Caliente 345 kV
2013 LW 115 kV
-14.2
Holloman 115 kV
As can be seen in the above table, there were no reactive power margin deficiencies
in either of the two 2013 Case 1 scenarios analyzed. The Q-V margin determined
in the 2013 LW Case 1 scenario assumed that the SVC device at the proposed
HVDC terminal would have a range of 50MVAC to 130 MVAR. The 2013 HS
Case 1 scenario margin was determined based on an SVC range of 0 MVAC to 130
MVAR. As stated previously, more detailed studies will be needed in order to
determine the exact size of the SVC device. The 345 kV Q-V reactive power
margin plots for 2008 HS and LW Case 2 scenarios can be found on pages 9-10 and
the 115 kV Q-V reactive power margin plots for these scenarios can be found on
pages 26-27 of Appendix 6.
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Interconnection At New Artesia 345 kV Bus
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El Paso Electric Company
May 2004
6.6 2013 Case 2
The 2013 HS and LW Case 2 scenarios simulated the existing EPE system with the
proposed HVDC terminal interconnection. As outlined in the WECC procedure for
determining reactive power margin, load was increased by 5% and the worst
contingency was analyzed. The margin was determined by identifying the critical
(weakest) bus on the system during the worst contingency. This case modeled a
2013 load pattern and the HVDC terminal output at 100 MW.
The following table shows the results of the 2013 HS and LW Case 2 analyses.
Available reactive margins for the critical buses on both the 345 kV and 115 kV
systems during a CA 345 kV line contingency are shown below.
2013 Case 2 – Available Reactive Margin during CA 345 kV Outage
System Condition
MVAR Margin
Critical Bus
2013 HS 345 kV
-131.4
Caliente 345 kV
2013 HS 115 kV
-13.8
Holloman 115 kV
2013 LW 345 kV
-31.1
Caliente 345 kV
2013 LW 115 kV
-14.0
Holloman 115 kV
As can be seen in the above table, there were no reactive power margin deficiencies
in either of the two 2013 Case 2 scenarios analyzed. The Q-V margin determined
in the 2013 LW Case 2 scenario assumed that the SVC device at the proposed
HVDC terminal would have a range of 50 MVAC to 130 MVAR. The 2013 HS
Case 1 scenario margin was determined based on an SVC range of 0 MVAC to 130
MVAR. As stated previously, more detailed studies will be needed in order to
determine the exact size of the SVC device. The 345 kV Q-V reactive power
margin plots for 2008 HS and LW Case 2 scenarios can be found on pages 11-12
and the 115 kV Q-V reactive power margin plots for these scenarios can be found
on pages 28-29 of Appendix 6.
6.7 2013 Case 3
The 2013 HS and LW Case 3 scenarios simulated the existing EPE system with the
proposed HVDC terminal interconnection. As outlined in the WECC procedure for
determining reactive power margin, load was increased by 5% and the worst
contingency was analyzed. The margin was determined by identifying the critical
(weakest) bus on the system during the worst contingency. This case modeled a
2013 load pattern and the HVDC terminal output at 150 MW.
The following table shows the results of the 2013 HS and LW Case 3 analyses.
Available reactive margins for the critical buses on both the 345 kV and 115 kV
systems during a CA 345 kV line contingency are shown below.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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El Paso Electric Company
May 2004
2013 Case 3 – Available Reactive Margin during CA 345 kV Outage
System Condition
MVAR Margin
Critical Bus
2013 HS 345 kV
-108.0
Caliente 345 kV
2013 HS 115 kV
-16.8
Holloman 115 kV
2013 LW 345 kV
-52.0
Caliente 345 kV
2013 LW 115 kV
-12.9
Holloman 115 kV
As can be seen in the above table, there were no reactive power margin deficiencies
in either of the two 2013 Case 3 scenarios analyzed. The Q-V margin determined
in the 2013 LW Case 3 scenario assumed that the SVC device at the proposed
HVDC terminal would have a range of 50 MVAC to 130 MVAR. The 2013 HS
Case 3 scenario margin was determined based on an SVC range of 0 MVAC to 130
MVAR. As stated previously, more detailed studies will be needed in order to
determine the exact size of the SVC device. The 345 kV Q-V reactive power
margin plots for 2008 HS and LW Case 2 scenarios can be found on pages 13-14
and the 115 kV Q-V reactive power margin plots for these scenarios can be found
on pages 30-31 of Appendix 6.
6.8 2013 Case 4
The 2013 HS and LW Case 4 scenarios simulated the existing EPE system with the
proposed HVDC terminal interconnection. As outlined in the WECC procedure for
determining reactive power margin, load was increased by 5% and the worst
contingency was analyzed. The margin was determined by identifying the critical
(weakest) bus on the system during the worst contingency. This case modeled a
2013 load pattern and the HVDC terminal output at 200 MW.
The following table shows the results of the 2013 HS and LW Case 4 analyses.
Available reactive margins for the critical buses on both the 345 kV and 115 kV
systems during a CA 345 kV line contingency are shown below.
2013 Case 4 – Available Reactive Margin during CA 345 kV Outage
System Condition
MVAR Margin
Critical Bus
2013 HS 345 kV
-67.1
Caliente 345 kV
2013 HS 115 kV
-21.8
Holloman 115 kV
2013 LW 345 kV
-23.8
Caliente 345 kV
2013 LW (W/Reactors)
-76.1
Caliente 345 kV
2013 LW 115 kV
-19.1
Holloman 115 kV
As can be seen in the above table, there were no reactive power margin deficiencies
in either of the two 2013 Case 4 scenarios analyzed. A sensitivity analysis was
performed on the 2013 LW Case 4 scenario to determine if the addition of the line
reactors on the proposed Artesia2-Caliente 345 kV line would have any additional
impact on the reactive margin. Results of this analysis indicates that the addition of
these reactors on the proposed line actually enhance the reactive margin on the
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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El Paso Electric Company
May 2004
system. Therefore, the worst cases in all the scenarios analyzed are the cases
without the line reactors modeled. Even in this case, there were no reactive margin
deficiencies in any of the cases analyzed. The Q-V margin determined in the 2013
LW Case 4 scenario assumed that the SVC device at the proposed HVDC terminal
would have a range of 50 MVAC to 130 MVAR. The 2013 HS Case 4 scenario
margin was determined based on an SVC range of 0 MVAC to 130 MVAR. As
stated previously, more detailed studies will be needed to determine the exact size
of the SVC device. The 345 kV Q-V reactive power margin plots for 2008 HS and
LW Case 2 scenarios can be found on pages 15-17 and the 115 kV Q-V reactive
power margin plots for these scenarios can be found on pages 32-33 of Appendix 6.
In conclusion, results of the Q-V analyses indicate that there is sufficient VAR margin on
the EPE transmission system to meet WECC criteria without having to make any
additional system upgrades other than the ones recommended in Section 4.0. These
analyses assume that the design of the proposed HVDC terminal will include an SVC
device with a range of at least 50 MVAC to 130 MVAR and that it will also be designed
to provide a 100% power factor correction. Again, more detailed analyses will have to be
performed in order to determine the exact size of this SVC device.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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El Paso Electric Company
May 2004
7.0
TRANSIENT STABILITY ANALYSIS RESULTS
Transient stability fault analyses on the Case1, Case 2, Case 3, and Case 4 scenarios were
performed for a three-phase 3.5 cycle bus fault. The loss of the proposed HVDC terminal
was analyzed in the 2008 and 2013 HS and LW cases in order to verify that this proposed
new interconnection does not violate WECC transient stability criteria. The transient
stability analysis was performed simulating the loss of the proposed Artesia2 345 kV bus.
The fault was cleared at 3.5 cycles and the Caliente-Artesia2 345 kV line was restored.
Plots of the analyses show a detail of what occurs before, during, and after the fault
occurs over a ten second time period.
NERC/WECC Planning Standards require that the transient voltage dip not exceed 25%
at load buses or 30% at non-load buses and that the minimum transient frequency not fall
below 59.6 Hz for 6 cycles or more at a load bus. Results of the analyses for each of the
cases are listed below.
7.1
2008 Case 1
The 2008 HS and LW Case 1 scenarios simulated the existing EPE system with the
proposed HVDC terminal output at 50 MW. These cases were analyzed for a threephase fault at the proposed Artesia2 bus as described in Section 7.0 above. The
tables below show the worst case transient voltage dips and frequency responses for
the 2008 HS and LW Case 1 Scenarios.
2008 CASE 1 WORST CASE VOLTAGE DIPS
CASE
2008 HS
2008 HS
2008 HS
2008 LW
2008 LW
2008 LW
BUS
% V DIP
White Sands 13.8(vbul)
Largo 115 (vbus)
Artesia2 345 (vbug)
Artesia 345 (vbul)
Amrad 115 (vbus)
Artesia2 345 (vbug)
1.40
1.90
2.20
2.25
1.00
1.05
2008 CASE 1 WORST CASE FREQUENCY RESPONSES
CASE
2008 HS
2008 HS
2008 HS
2008 LW
2008 LW
2008 LW
BUS
LOWEST
FREQUENCY (Hz)
Ruidoso 115 (fbul)
Leo 115 (fbus)
Newman G1 13.8 (fbug)
Chaparral 13.8 (fbul)
Milagro 115 (fbus)
Artesia2 345 (fbug)
59.95
59.97
59.98
59.96
59.95
59.97
Appendix 7 contains plots of the six worst case deviations of angle (ang), bus
voltage (vbu*) and bus frequency (fbu*) for the 2008HS and LW Case 1 scenarios.
Facilities Study For Proposed HVDC Terminal
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El Paso Electric Company
May 2004
The “*” represents “l” for a bus with load, “s” for a bus without load, or “g” for a
generator bus. The case was reviewed for conformance to the WECC criteria for
voltage and frequency deviations. As can be seen in the tables above, no criteria
violations were found in either the 2008 HS or LW Case 1 scenarios. Please refer
to pages 1-14 in Appendix 7 for the plots showing the results of the 2008 HS and
LW Case 1 transient stability analyses.
7.2
2008 Case 2
The 2008 HS and LW Case 2 scenarios simulated the existing EPE system with the
proposed HVDC terminal output at 100 MW. These cases were analyzed for a
three-phase fault at the proposed Artesia2 bus as described in Section 7.0 above.
The tables below show the worst case transient voltage dips and frequency
responses for the 2008 HS and LW Case 2 Scenarios.
2008 CASE 2 WORST CASE VOLTAGE DIPS
CASE
2008 HS
2008 HS
2008 HS
2008 LW
2008 LW
2008 LW
BUS
% V DIP
White Sands 13.8(vbul)
Amrad 115 (vbus)
Artesia2 345 (vbug)
White Sands 115 (vbul)
ArtesiaR 345 (vbus)
Artesia2 345 (vbug)
2.50
1.90
2.40
2.20
4.75
4.75
2008 CASE 2 WORST CASE FREQUENCY RESPONSES
CASE
2008 HS
2008 HS
2008 HS
2008 LW
2008 LW
2008 LW
BUS
LOWEST
FREQUENCY (Hz)
Artesia 345 (fbul)
Milagro 115 (fbus)
Newman G2 13.8 (fbug)
Artesia 345 (fbul)
ArtesiaR 345 (fbus)
Artesia2 345 (fbug)
59.90
59.95
59.96
59.98
59.97
59.95
Appendix 7 contains plots of the six worst case deviations of angle (ang), bus
voltage (vbu*) and bus frequency (fbu*) for the 2008HS and LW Case 2 scenarios.
The “*” represents “l” for a bus with load, “s” for a bus without load, or “g” for a
generator bus. The case was reviewed for conformance to the WECC criteria for
voltage and frequency deviations. As can be seen in the tables above, no criteria
violations were found in either the 2008 HS or LW Case 2 scenarios. Please refer
to pages 15-28 in Appendix 7 for the plots showing the results of the 2008 HS and
LW Case 2 transient stability analyses.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
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El Paso Electric Company
May 2004
7.3
2008 Case 3
The 2008 HS and LW Case 3 scenarios simulated the existing EPE system with the
proposed HVDC terminal output at 150 MW. These cases were analyzed for a
three-phase fault at the proposed Artesia2 bus as described in Section 7.0 above.
The tables below show the worst case transient voltage dips and frequency
responses for the 2008 HS and LW Case 3 Scenarios.
2008 CASE 3 WORST CASE VOLTAGE DIPS
CASE
2008 HS
2008 HS
2008 HS
2008 LW
2008 LW
2008 LW
BUS
% V DIP
Artesia 345 (vbul)
ArtesiaR 345 (vbus)
Artesia2 345 (vbug)
Amrad 24.9 (vbul)
Amrad 115 (vbus)
Artesia2 345 (vbug)
7.60
7.50
7.50
2.25
2.25
2.00
2008 CASE 3 WORST CASE FREQUENCY RESPONSES
CASE
2008 HS
2008 HS
2008 HS
2008 LW
2008 LW
2008 LW
BUS
LOWEST
FREQUENCY (Hz)
Chaparral 115 (fbul)
Milagro 115 (fbus)
Newman G2 13.8 (fbug)
Artesia 345 (fbul)
Newman 115 (fbus)
Newman G3 13.8 (fbug)
59.95
59.97
59.95
59.97
59.98
59.98
Appendix 7 contains plots of the six worst case deviations of angle (ang), bus
voltage (vbu*) and bus frequency (fbu*) for the 2008HS and LW Case 3 scenarios.
The “*” represents “l” for a bus with load, “s” for a bus without load, or “g” for a
generator bus. The case was reviewed for conformance to the WECC criteria for
voltage and frequency deviations. As can be seen in the tables above, no criteria
violations were found in either the 2008 HS or LW Case 3 scenarios. Please refer
to pages 29-42 in Appendix 7 for the plots showing the results of the 2008 HS and
LW Case 3 transient stability analyses.
7.4
2008 Case 4
The 2008 HS and LW Case 4 scenarios simulated the existing EPE system with the
proposed HVDC terminal output at 200 MW. These cases were analyzed for a
three-phase fault at the proposed Artesia2 bus as described in Section 7.0 above.
The tables below show the worst case transient voltage dips and frequency
responses for the 2008 HS and LW Case 4 Scenarios.
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May 2004
2008 CASE 4 WORST CASE VOLTAGE DIPS
CASE
BUS
2008 HS
2008 HS
2008 HS
2008 LW
2008 LW
2008 LW
% V DIP
Artesia 345 (vbul)
ArtesiaR 345 (vbus)
Artesia2 345 (vbug)
Amrad 24.9 (vbul)
Amrad 115 (vbus)
Artesia2 345 (vbug)
4.80
3.50
5.20
2.00
2.25
2.00
2008 CASE 4 WORST CASE FREQUENCY RESPONSES
CASE
BUS
2008 HS
2008 HS
2008 HS
2008 LW
2008 LW
2008 LW
LOWEST
FREQUENCY (Hz)
Artesia 345 (fbul)
Milagro 115 (fbus)
Newman G2 13.8 (fbug)
Artesia 345 (fbul)
ArtesiaR 345 (fbus)
Artesia2 345 (fbug)
59.98
59.97
59.96
59.90
59.95
59.96
Appendix 7 contains plots of the six worst case deviations of angle (ang), bus
voltage (vbu*) and bus frequency (fbu*) for the 2008HS and LW Case 4 scenarios.
The “*” represents “l” for a bus with load, “s” for a bus without load, or “g” for a
generator bus. The case was reviewed for conformance to the WECC criteria for
voltage and frequency deviations. As can be seen in the tables above, no criteria
violations were found in either the 2008 HS or LW Case 4 scenarios. Please refer
to pages 43-56 in Appendix 7 for the plots showing the results of the 2008 HS and
LW Case 4 transient stability analyses.
7.5
2013 Case 1
The 2013 HS and LW Case 1 scenarios simulated the existing EPE system with the
proposed HVDC terminal output at 50 MW. These cases were analyzed for a threephase fault at the proposed Artesia 2 bus as described in Section 7.0 above. The
tables below show the worst case transient voltage dips and frequency responses for
the 2013 HS and LW Case 1 Scenarios.
2013 CASE 1 WORST CASE VOLTAGE DIPS
CASE
2013 HS
2013 HS
2013 HS
2013 LW
2013 LW
2013 LW
BUS
% V DIP
Artesia 345 (vbul)
ArtesiaR 345 (vbus)
Artesia2 345 (vbug)
Amrad 24.9 (vbul)
Amrad 115 (vbus)
Artesia2 345 (vbug)
Facilities Study For Proposed HVDC Terminal
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2.20
1.50
2.85
1.00
0.50
1.00
El Paso Electric Company
May 2004
2013 CASE 1 WORST CASE FREQUENCY RESPONSES
CASE
BUS
2013 HS
2013 HS
2013 HS
2013 LW
2013 LW
2013 LW
LOWEST
FREQUENCY (Hz)
Artesia 345 (fbul)
Milagro 115 (fbus)
Artesia2 345 (fbug)
Artesia 345 (fbul)
ArtesiaR 345 (fbus)
Artesia2 345 (fbug)
59.95
59.90
59.92
59.82
59.82
59.82
Appendix 7 contains plots of the six worst case deviations of angle (ang), bus
voltage (vbu*) and bus frequency (fbu*) for the 2008HS and LW Case 1 scenarios.
The “*” can represent an “l” for a bus with load, “s” for a bus without load, or “g”
for a generator bus. The case was reviewed for conformance to the WECC criteria
for voltage and frequency deviations. As can be seen in the tables above, no criteria
violations were found in either the 2013 HS or LW Case 1 scenarios. Please refer
to pages 57-70 in Appendix 7 for the plots showing the results of the 2013 HS and
LW Case 1 transient stability analyses.
7.6
2013 Case 2
The 2013 HS and LW Case 2 scenarios simulated the existing EPE system with the
proposed HVDC terminal output at 100 MW. These cases were analyzed for a
three-phase fault at the proposed Artesia 2 bus as described in Section 7.0 above.
The tables below show the worst case transient voltage dips and frequency
responses for the 2013 HS and LW Case 2 Scenarios.
2013 CASE 2 WORST CASE VOLTAGE DIPS
CASE
2013 HS
2013 HS
2013 HS
2013 LW
2013 LW
2013 LW
BUS
% V DIP
Artesia 345 (vbul)
ArtesiaR 345 (vbus)
Artesia2 345 (vbug)
Amrad 24.9 (vbul)
ArtesiaR 345 (vbus)
Artesia2 345 (vbug)
2.94
2.94
2.85
2.85
1.96
1.96
2013 CASE 2 WORST CASE FREQUENCY RESPONSES
CASE
2013 HS
2013 HS
2013 HS
2013 LW
2013 LW
2013 LW
BUS
LOWEST
FREQUENCY (Hz)
Artesia 345 (fbul)
Milagro 115 (fbus)
Artesia2 345 (fbug)
Artesia 345 (fbul)
ArtesiaR 345 (fbus)
Artesia2 345 (fbug)
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
30
59.92
59.92
59.90
59.76
59.76
59.76
El Paso Electric Company
May 2004
Appendix 7 contains plots of the six worst case deviations of angle (ang), bus
voltage (vbu*) and bus frequency (fbu*) for the 2013 HS and LW Case 2 scenarios.
The “*” can represent an “l” for a bus with load, “s” for a bus without load, or “g”
for a generator bus. The case was reviewed for conformance to the WECC criteria
for voltage and frequency deviations. As can be seen in the tables above, no criteria
violations were found in either the 2013 HS or LW Case 2 scenarios. Please refer
to pages 71-84 in Appendix 7 for the plots showing the results of the 2013 HS and
LW Case 2 transient stability analyses.
7.7
2013 Case 3
The 2013 HS and LW Case 3 scenarios simulated the existing EPE system with the
proposed HVDC terminal output at 150 MW. These cases were analyzed for a
three-phase fault at the proposed Artesia 2 bus as described in Section 7.0 above.
The tables below show the worst case transient voltage dips and frequency
responses for the 2013 HS and LW Case 3 Scenarios.
2013 CASE 3 WORST CASE VOLTAGE DIPS
CASE
2013 HS
2013 HS
2013 HS
2013 LW
2013 LW
2013 LW
BUS
% V DIP
Artesia 345 (vbul)
ArtesiaR 345 (vbus)
Artesia2 345 (vbug)
Amrad 24.9 (vbul)
ArtesiaR 345 (vbus)
Artesia2 345 (vbug)
8.82
8.82
8.82
3.04
1.00
1.00
2013 CASE 3 WORST CASE FREQUENCY RESPONSES
CASE
2013 HS
2013 HS
2013 HS
2013 LW
2013 LW
2013 LW
BUS
LOWEST
FREQUENCY (Hz)
Artesia 345 (fbul)
Milagro 115 (fbus)
Artesia2 345 (fbug)
Artesia 345 (fbul)
ArtesiaR 345 (fbus)
Artesia2 345 (fbug)
59.90
59.90
59.90
59.74
59.74
59.74
Appendix 7 contains plots of the six worst case deviations of angle (ang), bus
voltage (vbu*) and bus frequency (fbu*) for the 2013 HS and LW Case 3 scenarios.
The “*” can represent an “l” for a bus with load, “s” for a bus without load, or “g”
for a generator bus. The case was reviewed for conformance to the WECC criteria
for voltage and frequency deviations. As can be seen in the tables above, no criteria
violations were found in either the 2013 HS or LW Case 3 scenarios. Please refer
to pages 85-98 in Appendix 7 for the plots showing the results of the 2013 HS and
LW Case 3 transient stability analyses.
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El Paso Electric Company
May 2004
7.8
2013 Case 4
The 2013 HS and LW Case 4 scenarios simulated the existing EPE system with the
proposed HVDC terminal output at 200 MW. These cases were analyzed for a
three-phase fault at the proposed Artesia 2 bus as described in Section 7.0 above.
The tables below show the worst case transient voltage dips and frequency
responses for the 2013 HS and LW Case 4 Scenarios.
2013 CASE 4 WORST CASE VOLTAGE DIPS
CASE
2013 HS
2013 HS
2013 HS
2013 LW
2013 LW
2013 LW
BUS
% V DIP
Artesia 345 (vbul)
ArtesiaR 345 (vbus)
Artesia2 345 (vbug)
Amrad 24.9 (vbul)
ArtesiaR 345 (vbus)
Artesia2 345 (vbug)
5.88
6.86
6.86
5.88
5.88
5.88
2013 CASE 4 WORST CASE FREQUENCY RESPONSES
CASE
2013 HS
2013 HS
2013 HS
2013 LW
2013 LW
2013 LW
BUS
LOWEST
FREQUENCY (Hz)
Artesia 345 (fbul)
Milagro 115 (fbus)
Artesia2 345 (fbug)
Artesia 345 (fbul)
ArtesiaR 345 (fbus)
Artesia2 345 (fbug)
59.90
59.90
59.90
59.80
59.80
59.80
Appendix 7 contains plots of the six worst case deviations of angle (ang), bus
voltage (vbu*) and bus frequency (fbu*) for the 2013 HS and LW Case 4 scenarios.
The “*” can represent an “l” for a bus with load, “s” for a bus without load, or “g”
for a generator bus. The case was reviewed for conformance to the WECC criteria
for voltage and frequency deviations. As can be seen in the tables above, no criteria
violations were found in either the 2013 HS or LW Case 4 scenarios. Please refer
to pages 99-112 in Appendix 7 for the plots showing the results of the 2013 HS and
LW Case 4 transient stability analyses.
In conclusion, the results of the transient stability analyses indicate that no criteria
violations occur in any of the 2008 and 2013 LW case scenarios. NERC/WECC
Planning Standards require that the transient voltage dip not exceed 25% at load buses or
30% at non-load buses and that the minimum transient frequency not fall below 59.6 Hz
for 6 cycles or more at a load bus. The tables above indicate that all the scenarios
analyzed were within the required NERC/WECC minimum planning criteria.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
32
El Paso Electric Company
May 2004
8.0 COST ESTIMATES
The following cost estimates are for system modifications required to meet WECC
reliability criteria if the proposed HVDC terminal is interconnected into the EPE
transmission system via a new 345 kV line from Artesia2 to Caliente 345 kV Substation
and a tie between Artesia2 and Artesia in the 2008 through 2013 time frame. Project
dollar amounts shown are in 2004 U.S. dollars. Labor and overhead costs are included in
these estimates.
The study results show that there are a few impacts to the EPE system when the proposed
HVDC terminal is interconnected into the EPE 345 kV system. Powerflow, Delta V and
Q-V analyses revealed overloading criteria violations of the Caliente and Arroyo 115/345
kV autotransformers during single contingency conditions. The estimated costs to correct
these criteria violations are shown below.
SYSTEM IMPACT ESTIMATED COSTS
SYSTEM MODIFICATION
3rd Caliente 200 MVA 115/345 kV autotransformer
2nd Arroyo 200 MVA 115/345 kV autotransformer
TOTAL SYSTEM IMPACT COSTS
YEAR
2008
2008
ESTIMATED
COST
(2004$)
$2,710,050
$2,710,050
$5,420,100
In addition, this Study assumed that a new 345 kV line from Artesia2-Caliente
Substations will be constructed to import the power into the EPE system. Cost estimates
to construct this new transmission line, add 50 MVAR line reactors, and perform the
required work at Caliente and Artesia2 Substations to connect the line are listed below.
CALIENTE-ARTESIA2 345 kV LINE ESTIMATED COSTS
SYSTEM MODIFICATION
New Artesia2-Caliente 345 kV line
50 MVAR reactor at Caliente end of 345 kV line and associated substation work
50 MVAR reactor at Artesia2 end of 345 kV line and associated substation work
TOTAL CALIENTE-ARTESIA2 345 kV LINE COSTS
YEAR
2008
2008
2008
ESTIMATED
COST
(2004$)
$104,550,000
$2,772,000
$2,897,000
$110.219,000
Therefore, the total cost of the project is estimated to be $115,539,100. It should be noted that
the costs for the design and construction of the proposed HVDC terminal have not been
included in this Study. Also, this Study assumed that a Static Var Compensating (SVC)
device will be included as part of the design of the proposed HVDC terminal. This Study
indicates that the SVC device should have a range of at least 50 MVAC to 130 MVAR.
However, a more detailed study will need to be performed to determine the exact size of the
SVC device. A previous Study performed in April 1999 estimated costs to construct an
HVDC terminal (including the SVC) similar to the one being studied here to be between $45
million and $50 million.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
33
El Paso Electric Company
May 2004
9.0 DISCLAIMER
Since the EPEGD proposed HVDC terminal interconnection will be used solely to serve
native load, this study assumed no transmission service to sell power out of the EPE
control area would be required and the output from the HVDC terminal will be delivered
to the EPE system. However, if in the future EPEGD decides to utilize this power to sell
to other entities outside of the EPE control area, EPEGD will have to purchase the
required transmission rights from the appropriate entity. This study makes no warranties
as to the existence or availability of that transmission. Also, the transfer capacities of
certain transmission lines and paths within the southern New Mexico transmission system
are limited by contracts between the New Mexico transmission owners and any use of the
transfer capacities above the contractual limits will require approval by the contractual
parties and renegotiation of the applicable contract(s).
This study also assumed that a new 345 kV line from the proposed HVDC terminal
(Artesia2) to Caliente Substation will be part of the interconnection configuration. If this
line is not constructed as part of the project, a re-evaluation of this study will need to be
performed to determine the impacts of importing up to 200 additional MW into the EPE
system without the assumed line (and corresponding line reactors).
The study also assumes that an SVC device will be included as part of the design of the
proposed HVDC terminal. Analyses in this study indicate that the system will require an
SVC with a range of between 50 MVAC to 130 MVAR. A more detailed study will be
needed to determine the exact size of this SVC device once the actual specifications of
the proposed HVDC terminal are known. The study also assumes that the terminal will
be designed to provide a 100% load factor correction similar to the modeling of SPS’
Blackwater 345 kV HVDC terminal.
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
34
El Paso Electric Company
May 2004
10.0 CERTIFICATION
El Paso Electric Company’s System Planning Department has performed this Facilities
Study as requested by El Paso Electric Company’s Generation Division (EPEGD). The
Study determined the impacts to the EPE system due to the interconnection of the
proposed HVDC terminal near Artesia, New Mexico and new Artesia-Caliente 345 kV
line. Analyses were performed for the 2008 and 2013 Heavy Summer and Light Winter
timeframes. The study recommended facility modifications to correct impacts due to the
addition of the proposed project and estimated costs for installing the required system
modifications. System Planning performed power flow, Delta V, Q-V reactive margin,
and transient stability analyses in this study.
Name:
Dennis H. Malone
Title:
Manager, System Planning
Signature:
Date:
Facilities Study For Proposed HVDC Terminal
Interconnection At New Artesia 345 kV Bus
35
El Paso Electric Company
May 2004