Quasi-Z源逆变器电压电流双闭环控制系统研究

A voltage-current close loop control algorithm for Quasi-Z source inverter

Quasi-Z源逆变器是在Z源逆变器的基础上提出来的新型电路拓扑结构,它除具有Z源逆变器的各种优点外,还降低了逆变器无源器件的电压电流额定值,而且使逆变器的输入电流变得连续,具有很好的应用前景。分析了Quasi-Z源逆变器的工作原理,建立了它的小信号模型,并设计了Quasi-Z源逆变器的电压电流双闭环控制系统。实现了对直流母线电压峰值的间接控制,能克服输入电压变化、负载变化等扰动的影响,使输出电压始终保持恒定,具有良好的动态性能和稳态性能。通过仿真验证了所建模型的准确性以及控制系统的有效性。

Quasi-Z source inverter is a novel inverter topology, which is based on the Z-source inverter. This novel inverter not only has various advantages of Z-source inverter, but also has lower passive component ratings as well as continuous input current, so it has good application prospect. The operation principle of Quasi-Z source inverter was analyzed in this paper, its small signal model was established, and a voltage-current closed loop controller for Quasi-Z source inverter was designed. By the above technique, a constant peak DC-link voltage could be achieved with an excellent transient performance which enhanced the rejection of disturbance, including the input voltage and load current variation. The simulation results prove the veracity of small signal model and the validity of the controller.