考虑零序电流抑制的开绕组永磁同步电机断相故障下统一调制策略

The Unified Modulation Scheme of Open-End Winding PMSM with Common DC Bus under the Open-Phase Fault Considering the Suppression of Zero-Sequence Current

研究电机相绕组断路下的容错控制对于提升系统的可靠性至关重要,但传统的共直流母线开绕组永磁同步电机(OW-PMSM)系统中的零序电流(ZSC)抑制策略在绕组断路故障下均不再适用。基于此,该文提出一种共直流母线OW-PMSM系统在绕组断相故障下的控制策略。通过建立同步坐标系下电流分量与静止坐标系下电流分量及零序电流之间的数学模型,分析同步坐标系下电流分量中的二倍频及四倍频分量与ZSC的关系,提出在同步坐标系下采用比例积分谐振控制器抑制ZSC的方法。此外,根据绕组断相故障下OW-PMSM系统电压矢量的分布规律,提出一种利用一组互相垂直的电压矢量进行统一调制来产生参考电压矢量的方案。因此,构建OWPMSM实验平台,对提出的断相故障下共直流母线OW-PMSM控制策略进行实验验证。

The research of the continuous fault-tolerant operation under open-phase fault is vital for the high reliability of the motor-drive system. However, in the open-phase fault of open-end winding permanent-magnet synchronous motor(OW-PMSM) system with common dc bus, the zerosequence current(ZSC) cannot be suppressed with the conventional schemes. On this basis, a novel control scheme is proposed for the OW-PMSM system with open-phase fault. By investigating the relationship among the currents in synchronous coordinate system, the currents in stationary coordinate system and ZSC, the proportional resonance controller-based control scheme is proposed to suppress the 2 nd and 4 th harmonic currents in ZSC. Moreover, according to the distribution of voltage vectors under the open-phase fault, a unified modulation scheme, which can be applied to simplify the modulation process by synthesizing the reference voltage with two orthogonal voltage vectors, is proposed. Finally, the experimental platform of the OW-PMSM system is built to validate the effectiveness of the proposed control scheme.