基于H_∞控制与最优跟踪控制相结合的三相PWM整流器控制策略

摘要

This paper proposes a mixfure of H∞ control and optimal tracking control method for the three-phase PWM rectifier.This paper presents an optimal control for the inner current loop control without decoupling.And a H∞ control method for the outer voltage loop is proposed.Based on the mathematical model of the PWM rectifier,state equations are established for the standard setup of the H∞ control problem.Suitable weighting functions are selected for the system.The Riccati inequality is solved to derive the H∞ control.Because of the underdetermined parameters,the system is hardly to obtain an optimal performance with the calculated parameters of the controller.Based on the particle swarm optimization(PSO)algorithm,an improved PSO algorithm is designed to optimal the parameters of the system with the wonder of the simulated annealing(SA)algorithm and the chaotic search.And then,the performance of PWM rectifier system is better.Simulation and experiment results verify that the proposed control system is suitable and effect for the PWM rectifier.%针对三相PWM整流器的特点,提出了一种基于H∞控制与最优跟踪控制相结合的混合控制策略。电流内环,采用了最优控制策略,无需解耦;电压外环,采用H∞控制策略。基于PWM整流器的数学模型,建立了满足H∞控制标准型的状态方程,并选择合适的权函数。通过求解Riccati不等式,得到H∞控制器。由于混合控制器待定参数较多,计算所得控制器参数难以保证系统运行在最优状态中。本文基于PSO算法,结合模拟退火以及混沌搜索的优点,设计了一种改进的PSO算法,对所设计控制器进行参数整定和优化,进一步提高了PWM整流器的控制性能,具有更好的动态性能和抗干扰性。仿真和实验证明了本文所提出方法的可行性和有效性。