抽水蓄能机组调速系统非线性预测控制方法研究

调速系统是抽水蓄能机组频率及出力控制的主要部件,其控制性能及控制品质对于工况变化频繁,在电网中担任削峰填谷任务的抽水蓄能机组尤为重要。本文针对传统抽蓄机组的PID控制器中控制参数受工况影响大,控制器缺乏状态预测能力等缺点,提出一种适用于抽蓄机组调速系统不同工况的快速非线性预测控制方法。该方法应用抽蓄机组全特性曲线作为水泵水轮机模型,考虑压力引水管道的水击现象,利用模糊PID控制与预测控制的滚动状态预测原理计算得到调速器控制信号,使得调速器在根据运行工况精确控制机组频率与出力的同时,保证了控制计算的实时性。通过以某抽水蓄能电站实际资料进行抽水蓄能机组发电方向开机和负荷调节动态过程仿真,结果表明该预测控制方法较传统控制方式效果优越。

Nonlinear Predictive Control Method for Pumped Storage Unit Governing System

Turbine governing system is the major part for rotating speed and output mechanical power control.Its control performance is paramount for the pumped storage units that undertake the tasks of peak load shifting.To overcome the shortcomings of conventional PID control method in its weakness of parameters seriously affected by working conditions and of its limited performance in state prediction,this paper proposed a fast nonlinear predictive control method which is suitable for the power output adjusting case of the governing system of pumping storage turbines.This control strategy puts the complete characteristic curves of the pump turbine which has been widely recognized in the field into application and takes account of the water-hammer effect of the pressure pipeline.It calculates the control signal based on the integration of fuzzy PID control and the model predictive control,which makes the governor precisely control both the speed and power of the unit with its computational speed guaranteed.The proposed predictive control method and the conventional PID method along with fuzzy PID method have been applied under both the start-up and load schedule conditions which are simulated according to the measured data of a pumping storage unit.The simulation result indicated the preponderance of the proposed control compared with the conventional control.