多电平变换器PWM控制技术研究现状综述及最新进展

Overview of PWM Control Technology for Multi-level Converters and Its Recent Progress

近年来,多电平变换器成为高压、大功率电力电子系统应用领域的一个研究热点,而多电平脉宽调制PWM(pulse width modulation)控制方法是多电平变换器研究领域的核心问题之一。首先,阐述了3种载波PWM控制方法,并根据不同的控制指标介绍了各类优化载波PWM控制方法;其次,介绍了传统空间矢量脉宽调制SVPWM(space vector pulse width modulation)算法,并根据算法优化及控制指标详细介绍了不同坐标变换下的SVPWM,着重阐述了虚拟SVPWM及在其基础上衍生的各类优化虚拟空间矢量PWM在中点电压平衡控制中的应用;最后,介绍了n电平任意段多电平SVPWM与SPWM之间的本质联系,以及根据其统一性提出的优化PWM算法。

In recent years,multi-level converters have become a research hotspot in the application field of high-voltage and high-power power electronic systems,and the multi-level pulse width modulation(PWM)control method is one of the core issues in the research field of multi-level converters.In this paper,three kinds of carrier PWM control method are described at first,and various optimized carrier PWM control methods are introduced according to different control indexes.Then,the traditional space vector PWM(SVPWM)algorithm is introduced.In particular,the SVPWM under different coordinate transformations is introduced in detail according to the algorithm optimization and control index,and the applications of virtual space vector PWM and various optimized virtual space vector PWMs derived therefrom to neutral-point voltage balance control are emphasized.Finally,the essential relationship between n-level arbitrary segment multi-level SVPWM and SPWM is discussed,together with the optimized PWM algorithm which is proposed based on the corresponding unity.