Failure Analysis and Control Optimization of RB Test Due to Feed-water Excess Reducing for the 1000MW Ultra-supercritical Once-through Unit

3rd International Symposium on Resource Exploration and Environmental Science

生态环境科学

Xing, Zhiwei^1 ; Wang, Li^2 ; You, Mo^1 ; Li, Weihua^1 ; Luo, Yi^1 ; Shang, Yong^1 ; Gao, Aiguo^1

North China Electric Power Research Institute Co. Ltd, Beijing

100045, China^1

North China Electric Power Research Institute (xi'An) Co. Ltd, Xi'an

710065, China^2

关键词: Analysis and controls;    Control logic;    Effect of temperature;    Feed pumps;    Once through;    Pressure changing;    Supercritical;    Supercritical units;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/300/4/042128/pdf
DOI  :  10.1088/1755-1315/300/4/042128

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

As for the 1000MW ultra-supercritical unit of Beijiang Power Generation Co., Ltd, the FDF runback test (RB) is failed for the excess reducing of feed-water flow, and the reason is analized. In order to optimize the RB control logic, the method by using "slow-to-fast" pressure changing rate is applied during the RB process. Besides, the slowly interlock opening control logic of the motor-driven valve is added, which controls the inlet steam from auxiliary steam to feed pump steam turbine, in order to keep the inlet steam stable. In addition, the lag time of boiler to feed-water demand and the prohibit increasing time of fuel master are both increased, which benefit to the control effect of temperature. The test results show that, control logics after optimization can ensure the load reducing promptly and steadily during the runback process of the unit, and the transition of major parameters remains smooth.