关键词: 火力发电厂, 给水泵, 给水泵再循环控制, 优化, 控制策略, 电厂辅机, PID调节, 协同控制

Abstract: The feedwater pump is one of the most important auxiliary equipments of thermal power plants. It constitutes the water supply system which is essential to the unit safe and economic operation. In order to improve the secure and economic operation level of the water supply system, in combination with the analysis of the related fault mechanism, the optimized control strategy of the feedwater pump recirculation system is put forward after systematic research and testings. This optimized strategy is established according to the relationship between the speed and flow of the feedwater pump on the basis of the new PID control with three-layer coordinated controls. The implementation of the optimized PID closed-loop control strategy can not only improve the security of the unit, but also reduce the energy consumption of the recirculation system as well as the valve repair costs. The security and economics of the system with optimized control is verified through testing.

Key words: thermal power plant, feedwater pump, feedwater pump recirculation control, optimization, control strategy, auxiliary equipment, PID control, coordinated control