一种基于比例谐振控制的三相四线PWM整流器研究

对于三相四线制整流器系统,当电网电压和负载电流不平衡或者存在畸变时,应用d-q坐标变换后,传统的基于比例-积分（PI）控制器的矢量控制系统无法获得零稳态误差.鉴于比例-谐振（proportional-resonant）控制器在交流信号输入调节上具有良好的性能,本文提出了基于比例-谐振（PR）控制器来实现三相四线PWM整流控制策略,简化了控制系统的结构,在输入电压畸变以及不平衡情况下能实现电压跟踪运行.针对串联电容均压问题,本文从理论上分析了两组电容电压不平衡的原因,提出了相应的抑制方法.最后在MATLAB上建立了相应的仿真模型,仿真结果表明该控制方法有效性.

Study on Three Phase Four Wire PWM Rectifier Based on Proportional-Resonant Control

For three phase four wire rectifier system, When grid voltage and load current imbalance or distortion, using synchronous dq transformation, The vector control system based on PI controller can not get zero static error, as the proportional-resonant（PR） controller has good advantage in AC signal regulate, This paper propose three phase four wire PWM rectifier control strategy based on PR control, simplified the control system structure, It can realize the voltage tracking operation when voltage imbalance. The voltage unbalance between the two group capacitors was analyzed and the corresponding restrain method was provided. The simulation model is built in MATLAB/Simulink at last, The simulation results verify the validity of the control strategy.