基于电压空间矢量的类正弦滞环电流控制策略

A Voltage Vector-Based Sine-Like Hysteresis Current Control Strategy

滞环电流控制（hysteresis current control,HCC）是一种传统的电流控制方法,其实现简单、鲁棒性好、动态响应快。但当应用到三相系统时,由于三相间的耦合,会存在电流谐波大、开关频率过高等缺点。该文首先回顾了近年来为解决传统滞环控制自身问题而提出的一种改进的基于空间矢量的滞环电流控制（improved space vector-based HCC,ISV-HCC）方法的优缺点,然后提出了一种新型的基于电压空间矢量的类正弦滞环电流控制方法。该方法参考了空间矢量脉宽调制（space vector pulse width modulation,SVPWM）调制中的电压矢量概念,根据系统参数给定上下两滞环带,且当三相电流误差均在规定的滞环内时,采用零电压矢量开关模式,而当电流误差超出规定的滞环带时,则按照指定的逻辑对三相开关进行控制。最后,通过与传统HCC及ISV-HCC进行并网仿真与实验对比,证明该文所提出的方法具有更低的电流谐波及更小的开关频率,整体上具有更优的控制性能。

Conventional hysteresis current control（C-HCC） is a conventional control method with good robust and transient performance. However, due to interphase dependency, when it is used in three-phase system, high switching frequencies and current harmonics arise. This paper starts with a review of improved space vector-based HCC（ISV-HCC） reported to address the problem of conventional HCC. Then, a voltage vector-based sine-like HCC（SL-HCC） was proposed. The proposed SL-HCC refers to zero vector concept in space vector pulse width modulation（SVPWM） and sets a hysteresis band. When current errors are all within prescribed hysteresis bandwidth, zero vector switching pattern is adopted; and when current errors exceed the bandwidth, specified switching logic is adopted. Finally,by comparing with C-HCC and ISV-HCC,simulation and experiment results illustrate that SL-HCC performance is significantly improved with minimized current harmonics and lower switching frequency.