基于连续空间矢量脉宽调制(SVPWM)的三相VIENNA整流器输入电流存在过零畸变,导致输入电流总谐波畸变率升高的问题.为了消除过零畸变,该文从共享矢量的角度对过零畸变产生的原因进行深入的分析,并比较连续SVPWM和断续SVPWM各自存在的优势与不足,进而提出一种混合SVPWM策略,可以有效解决过零畸变问题.此外,还从共模电压的角度对两种脉宽调制进行归一化处理,优化混合SVPWM的算法实现.最后,通过仿真和实验验证了所提控制策略的正确性.

Multipulse ac/dc rectifiers (MPRs) are widely used in aviation applications due to their rugged structure, cost effective, and high-reliability features. In this article, an overview of the recent advances and trends on the MPR technology, mainly the autoconfigured transformer-based MPRs, and its application in more electric aircrafts is performed. This article covers system topologies, transformer configurations, passive and active harmonic reduction schemes, case study, practical selection and design guidelines, and applications. To fairly evaluate the performances of MPRs with different pulse numbers, necessary simulation studies are carried out under comparable conditions, including power rating, input and output specifications, and transformer configuration. Then, an 18-pulse asymmetric delta-polygon configured prototype is established based on the simulation evaluation and experimental verification is performed. It is expected that this article can provide a broad perspective on MPR technology, and, in particular, highlight the latest emerged technology that significantly promotes the performances of MPRs. More importantly, it is desired that the results obtained in this article can provide an effective selection guideline and design suggestion for researchers and engineers engaged in designing MPRs, especially for aviation applications.

Three-phase VIENNA rectifier with carrier-based pulse-width modulation (CBPWM) is widely used in various fields for its simple structure and high reliability. However, continuous high switching frequency of very semiconductors leads to considerable switching losses. The carrier-based discontinuous modulation (CB-DPWM) method is a preferable method to avoid the switching losses and achieve high efficiency. However, it results in extra issues around the zero-crossing area, causing current distortion. Therefore, a compensation strategy is deployed to address this problem. Moreover, a retrofit zero sequence component injection method is proposed to enhance the neutral-point potential balance ability of the CB-DPWM method. The feasibility of the employed methods are verified by simulation.