基于电压误差的五相内嵌式永磁同步电机两相开路多矢量模型预测容错控制

Two-phase open-circuit multi-vectors model predictive fault-tolerant control for five-phase IPMSM based on voltage errors

五相内嵌式永磁同步电机(interior permanent magnet synchronous motor, IPMSM)发生两相开路故障后,由于两相的缺失,重构后的电压矢量数目减少且分布不均,将影响模型预测控制(model predictive control, MPC)方法的预测精度.而现有的多矢量模型预测控制方法缺乏对电机两相故障工况下的分析.为此,针对两相开路故障,提出一种基于电压误差的多矢量模型预测控制方法.该方法的关键在于在扇区三角形内以等分线段的方式扩展电压矢量的组合,并且推导两相开路故障后的参考电压预测方程和电压误差价值函数来简化多个矢量选择和合成过程.该方法适用于故障工况下不对称形状的扇区,同时兼顾了内嵌式电机d-q轴电感不等的特性.最后通过实验验证该方法的动态、稳态性能和鲁棒性,该方法能实现五相内嵌式永磁同步电机的高品质两相开路容错运行.

When two-phase open-circuit fault occurs in the five-phase interior permanent magnet synchronous motor(IPMSM),the reconstructed voltage vectors are reduced in number and unevenly distributed due to the loss of two phases,which will affect the predictive precision of model predictive control(MPC).Nevertheless,the existing multi-vectors model predictive control methods lack the analysis of two-phase fault.Hence,targeting the two-phase open-circuit fault,this paper proposes a multi-vector MPC fault-tolerant method.The key of this method is to expand the combination of voltage vectors by dividing line segments in the sector triangle.Simultaneously,the process of multi-vectors selection and synthesis is simplified by deriving the reference voltage prediction and the cost function consisting of voltage errors after two-phase open-circuit fault.This method is suitable for sectors with asymmetrical shapes under fault operation and takes the unequal d-q axis inductance characteristics of the interior motor into consideration.Finally,the dynamic and steady performance of this method is verified by experiments and the proposed method can realize the high quality two-phase open-circuit fault-tolerant operation of the five-phase IPMSM.