基于正常解耦变换的双三相永磁同步电机缺相容错控制策略

常用的多相电机缺相容错控制策略需要建立缺相后的降维数学模型,双三相电机缺相时具有两种不同中性点连接方式,每种情况对应不同的解耦变换阵,需要分别进行建模。根据双三相电机开路故障时,如果保持系统解耦变换阵不变,则电压方程、磁链方程和转矩方程不会受到影响的特点,构建了一种基于正常解耦变换阵的缺相容错控制策略,该策略适用于不同中性点连接方式,只需要改变谐波子空间参考电流即可。分别对定子铜耗最小和最大转矩输出两种优化电流工作方式进行分析,并分析了3次谐波磁动势对电磁转矩的影响。对一相开路和正交两相开路情况分别进行理论分析和实验验证,证明了所提控制策略的有效性和可行性。

The Control Strategy for Dual Three-phase PMSM Based on Normal Decoupling Transformation under Fault Condition Due to Open Phases

The common fault-tolerant control strategy for multiphase machines needs to set up the reduced order system model.There are two different neutral connections for dual three-phase permanent magnet synchronous motor (PMSM) under open phase conditions,and each case corresponds to a different decoupled transformation matrix,so they need to be modeled,respectively.When an open-phase fault occurs for dual three-phase machine,the voltage,flux,and torque equations are unaffected by the fault.The fault-tolerant control strategy based on normal decoupling transformation is constructed in this paper.This control strategy is suitable for the two different neutral connections,and only modifications of current references in the harmonic subspace are needed.Two optimal current control modes of minimum stator loss and maximum torque output are analyzed.The influence of three harmonic magnetic potential on the electromagnetic torque is analyzed.Theoretical analysis and experimental verification were done for one open phase and two orthogonal open phases.The experimental results demonstrate the effectiveness and feasibility of the proposed strategy.