基于切换线性系统的单相有源电力滤波器的建模与控制

Modeling and Control of Single Phase Active Power Filter Based on Switched Linear System

为研究具有典型混杂动态特性的单相有源电力滤波器(single phase active power filter,SPAPF)的高性能控制问题,作者采用脉宽调制技术将包含SPAPF的混杂系统模型转化为包含切换开关的线性系统模型,通过在平衡流形邻域对其进行近似线性化得到了以脉宽为输入函数的线性离散系统,并为该系统设计了能够实时跟踪补偿指令电流的线性二次最优数字控制器。该控制器以脉宽为控制量,物理意义清晰、设计思路合理、易于在工程中实现。仿真结果验证了上述系统模型和控制器的正确性和有效性。

To research the high performance control of single phase active power filter （SPAPF） with typical hybrid dynamic characteristic, on the basis of pulse width modulation （PWM） the authors change the hybrid system model containing SPAPF into an equivalent discrete linear system （EDLS） model containing change-over switches; by means of approximately linearization of EDLS model in balance manifold neighborhood, a linear discrete system, which takes the pulse width as input function, is obtained, then an optimal digital linear quadratic controller is designed for this linear discrete system, which adopts the pulse width as control variable and can trace and compensate the instruction current in on-line mode. The physical meaning of this controller is clear, the thinking for the design is rational and easy to implement in engineering practice. Simulation results validate the correctness and effectiveness of above-mentioned system model and controller.