采用IMC-PID增强超临界机组功率控制的鲁棒性

介绍了一种机组协调控制系统，其在汽轮机主控回路中采用基于闭环辨识模型的IMC-PID方法，采用该方法解决火电机组功率振荡的问题。该方法首先通过闭环回路的设定值阶跃扰动试验，对测取的试验数据进行频率响应特性辨识，估计闭环控制过程中的频率响应矩阵和变换函数矩阵，用最小二乘法计算得出被控对象的模型。然后基于辨识出的模型，通过使用内部模型控制(IMC)方法，设计出汽轮机主控回路的鲁棒 PID 控制器。火力发电厂现场实际应用表明:汽轮机主控采用IMC-PID 控制器后，具有较好的鲁棒性，能够较好地抵御各种电网的外扰及发电过程内扰的影响，避免机组功率振荡。

Robustness Enhancement of Supercritical Unit Power Control with IMC-PID Controller

This paper proposes a novel boiler-turbine coordinated control system in which the IMC-PID controller is adopted to tackle the power oscillation problem based on closed-loop identification in the turbine control loop. The set-point additive step disturbance is first imposed onto the closed loop to carry out frequency response characteristic identification using process inputs and outputs of the control loops. The process frequency-response matrix is then estimated, and a transform function matrix is obtained with the least square method. The robust PID controller of the turbine control loop is finally designed by using the internal model control(IMC) method based on the previously obtained model. The practical application shows that the IMC-PID controller maintains the robust performance and minimizes the effects of the external or the internal disturbances in the power plant, thus the occurrence of the power oscillation can be avoided.