三相四线PWM整流器的一种新型零静差控制策略研究

A Novel Control Strategy for 400Hz Three-Phase Four-Wire PWM Rectifiers with Zero Steady-State Error

针对400Hz三相四线PWM整流器的特点,应用新型的虚拟正交变换方法设计了一种新型的控制策略,以实现输入电流零静差控制和各相独立控制。本文重点分析了该控制器的数学模型和系统控制框图,并通过调节PWM调制波的直流偏置来实现输出串联电容的均压控制;同时,通过对传统的SPWM技术加以改进,从而减小中线电流的纹波;最后,通过仿真和实验验证了该控制策略的可行性。该控制策略具有设计简单、易模块化的特点。

For the 400Hz three-phase four-wire PWM rectifier, a new control strategy is presented in this paper by using a novel virtually orthogonal transform to achieve zero steady-state error and independent control of each phase. The paper analyzes the model of the controller and its block diagram in detail, achieving the voltage balance in serial output-capacitor by adjusting DC bias in the PWM modulation wave. The control scheme also reduces the ripple in the current by improving the traditional SPWM. Finally, the control strategy is verified by the simulation and experiment results, with the features of easy design and modularization.