五相永磁同步电机缺相运行的建模与控制

为提高五相永磁同步电机(PMSM)控制系统的可靠性,减小定子绕组发生开路故障时电机输出转矩的脉动分量,提出了五相PMSM缺相运行时的容错控制策略。从矢量空间解耦的角度,建立了含有3次谐波磁场的五相PMSM缺相运行时的数学模型。根据瞬时功率守恒原理,对故障前后的电磁转矩进行分析,提出了平均转矩保持不变的容错控制策略,通过重新分配各相电流的幅值和相位,实现了控制系统的满负荷运行;为了使电机在缺相故障时仍能提供平滑转矩,提出了脉动转矩保持为零的容错控制策略,实现了控制系统的无扰运行。采用转子磁场定向的方法,通过对旋转坐标系下的交直轴电流和零序电流进行控制,实现了对电机输出转矩的补偿。实验结果表明,所提出的容错控制算法能够有效改善五相PMSM在定子绕组发生开路故障时的运行性能。

Modeling and Control of Five-Phase Permanent Magnet Synchronous Motor with One Phase Open-Circuit Fault

To improve the reliability of five-phase permanent magnet synchronous motor (PMSM) control system and reduce the ripple components of output torque when the stator windings occur open-circuit fault, this paper proposed an effective fault-tolerant control strategy for five-phase PMSM. Based on the viewpoint of vector space decoupling, a mathematical model of the five-phase PMSM with third harmonic injection was established. According to the power conservation principle, the electromagnetic torque was analyzed under normal state and fault state, then a fault-tolerant control strategy with unchanged average torque was proposed. This method realizes full-load operation by reallocating the amplitude and phase of the phase current. To obtain a smooth electromagnetic torque under fault state, another fault-tolerant control strategy was then proposed keeping the pulsating torque at zero, which realizes no-disturbed operation. By controlling the electric currents of dq axis and zero sequence in the rotating coordinate system, the electromagnetic torque was compensated. The experimental results show that the proposed fault-tolerance control strategy can improve the running performance of five-phase PMSM under fault state.