基于模型预测控制算法的供热机组负荷控制

Load control of heating unit based on model prediction algorithm

供热机组协调控制系统目前采用PID控制器,该控制器在发电功率调节过程中会使机组汽轮机机前压力与供热抽汽流量产生波动,同样在供热抽汽流量调节过程中会使汽轮机机前压力与发电功率产生波动。对此,以330 MW供热机组为研究对象,在非线性的供热机组模型基础上辨识得到线性的机组状态空间模型,以状态空间模型为基础进行状态变量与机组输出预测;然后根据供热机组输入、输出变量设计供热机组模型预测控制器,模型预测控制器经过输出预测、滚动优化后完成机组的协调控制。变工况仿真实验结果表明:模型预测控制方案具备可行性;相较于PID控制方案,模型预测控制方案能解决负荷调节过程中供热机组其他输出的波动问题。

At present,the coordinated control system of heating units adopts PID controller,but the pressure in front of the steam turbine and the heating extraction flow of the unit will fluctuate in the process of generating power regulation.Similarly,the pressure in front of the steam turbine and the generating power will fluctuate in the process of heating extraction flow regulation.To solve the above problems,a 330 MW heating unit is taken as the research object to identify the linear state space model of the unit based on the nonlinear heating unit model,and forecast the state variables and unit output based on the state space model.According to the input and output variables of the heating unit,the model predictive controller of the heating unit is designed.The model predictive controller completes the coordinated control of the unit after output prediction and rolling optimization.The simulation test under varying load condition shows that,the model predictive control scheme is feasible.Compared with the PID control scheme,the model predictive control scheme can solve the fluctuation problem of other outputs of heating units in the process of load regulation.