Fluctuations in steam temperature
reduced to less than ± 2 K
in Dingzhou, China
SPPA-P3000 Temperature Optimizer
reduces temperature fluctuations and permits an
increase in setpoints, thus increasing efficiency.
The Plant
The two 600 MW coal-fired units of Hebei Guohua
in Dingzhou, China were completed in 2004.
The drum-type boilers and turbines are licensed
GE products of the Shangai Electric Group and
the process control system is SPPA-T2000.
The Task
Due to large fluctuations in steam temperature,
the temperature setpoints regularly had to be
reduced manually to levels significantly below the
design value so as to avoid violation of permitted
limits. This was especially the case during load
ramps. The result was a significant reduction in
efficiency. The task was to reduce the fluctuations
in steam temperature in all load situations to such
an extent that a reduction in efficiency due to
reduced steam temperatures could be avoided.
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associated companies or the
individual holder.
The information in this document
contains general descriptions
of the technical options available, which
are not necessarily implemented in all
Individual cases. The required features
should therefore be specified in each
individual case at the time of closing
the contract.
550
100
„
Greater efficiency due to higher average
steam temperature
„
Fully automatic operation of temperature
controls without manual intervention
550
100
540
70
540
70
40
530
Time / min
530
0
20
HP steam temp. A
40
60
80
HP steam temp. B
100
120
140
HP steam temp. setpoint
160
Load
Situation prior to implementation of SPPA-P3000: Slow load ramps,
major temperature fluctuations, temporary setpoint decreases
Process Optimization References
Power Generation
The Result
Load / %
P311TO_FR_Dingzhou_e_V1-0
Shang Wei PM of project (CIO) Hebei Guohua
Dingzhou Power Generation Co. Ltd.
Temperature/°C
Siemens AG
Power Generation
Instrumentation & Controls
Siemensallee 84
D-76187 Karlsruhe
[email protected]
www.siemens.com/sppa-p3000
Our Solution
SPPA-P3000 Temperature Optimizer detects critical
heat input perturbations at an extremely early
stage and automatically initiates prompt
countermeasures. The basis for the solution
includes online models of non-linear superheater
time behavior and model-based monitoring
structures. Even age-related changes in valve
characteristics are automatically detected and
compensated.
In this way temperature deviations can be
restricted to the extraordinarily low level of ± 2K
"We have solved the problem of
temperature fluctuations completely
through the use of SPPA-P3000
Temperature Optimizer."
Load / %
Siemens AG
Power Generation
Freyeslebenstraße 1
D-91058 Erlangen
during load ramps with gradients of 4%/min. Even
in exceptional situations, ± 5K is not exceeded.
Temperature/°C
Published by and Copyright © 2008
Increased efficiency for Dingzhou power plant in China thanks
to SPPA-P3000 Temperature Optimizer
Instrumentation & Controls
Time / min
0
20
HP steam temp. A
40
60
80
HP steam temp. B
100
120
140
HP steam temp. setpoint
40
160
Load
Situation subsequent to implementation of SPPA-P3000: Fast load
ramps, minor temperature fluctuations, no setpoint decreases