三相电压型PWM整流器建模和仿真研究

三相电压型PWM整流器(VSR)广泛用于AC/DC/AC系统前端整流.考虑到VSR本身非线性特点,建立适合于控制器设计上的数学模型比较困难,提出了一种状态反馈解耦控制电流内环和直流电压平方外环的电压型PWM整流器新型控制策略,基于功率平衡理论,采用解耦状态反馈控制方法,分析并建立了三相电压型PWM整流器d-q坐标系下的线性化数学模型.由于采用直流电压平方外环,使典型的非线性模型线性化,控制器设计直观精确,提高了直流电压和网侧电流的跟踪能力,改善了波形.提出了一种空间矢量的简化算法,简化了运算过程.在MATLAB/SIMULINK环境中建立了仿真模型.仿真结果表明:所设计整流器具有优良的稳态性能和快速的动态响应,实现简单,具有一定的实用价值.

Modeling and Simulation Research for Three-Phase Voltage Source PWM Rectifier

Pulse-Width Modulated three-phase Voltage Source Rectifier (VSR) is the building blocks of the most of AC/DC/AC systems as the front-end rectifier. The major difficulty in control is caused by the nonlinearities in the rectifier model. The linear mathematical model of VSR in d-q coordinates was deduced with analysis based on the power balance equation. A new control strategy using inner current loop with state feedback decoupling and outer voltage square loop was proposed. Nonlinear input transformation was used to derive a linear model from the original nonlinear model. The advantages of the proposed scheme include accuracy controller design, fast dynamic response and high quality of the current and voltage waveforms. A simplified algorithm was proposed for space vector PWM (SVPWM) rectifier. The whole system was modeled and simulated by using the toolbox of MATLAB/SIMULINK. Simulation results show that the PWM model proposed can satisfy steady-state characteristics and fast transient response. This design scheme has some value for practical operation due to its simple implement.