模型预测控制算法是以系统模型为基础,通过优化性能指标获得最优控制量的一种新型算法,具有很好的控制性能,已经获得广泛的应用。针对三相电流型PWM整流器,本文提出了一种改进型模型预测控制。根据电流型PWM整流器在dq0旋转坐标系下的数学方程,建立了增量式预测控制模型;根据系统控制要求设计了控制器的优化性能指标,性能指标综合考虑了系统误差和控制增量的影响,通过求解优化性能指标得到预测控制增量表达式。实验结果表明,该控制算法具有很好的控制性能。相比于传统的PI调节器,该控制方法参数易整定,且具有很好的阻尼特性。
Model predictive control( MPC) is a novel control algorithm which is based on the mathematical model of the system,and the optimal control expression is obtained by optimizing the designed performance index. MPC can achieve a satisfactory control performance and has been widely used. In this paper,an improved MPC algorithm is proposed and is applied in current control for three-phase current source PWM rectifier( PWM-CSR). Increment predictive control model of the system is constructed based on the mathematical model of the CSC in dq0 rotating coordinates. According to the system control requirement,the optimal performance index in which the system error and control increment are considered is determined,and the expression of control increment is given. Experimental results show that MPC has a good performance. Meanwhile,as compared with the traditional PI controller,the MPC algorithm parameters are easy to be adjusted and has good damping characteristics