基于区间电流的SRM功率变换器短路故障诊断

Short-circuit fault diagnosis of SRM power converter based on interval current

功率变换器是开关磁阻电机(SRM)调速系统的核心部件之一,也是系统可靠性最弱的环节。针对传统功率变换器短路故障诊断需增加额外硬件、控制器负担大、诊断范围有限等问题,以非对称半桥式功率变换器为研究对象,在深入分析短路故障模式的基础上,为提取明显的故障特征,对电流传感器进行了重新排布,提出了基于特定转子位置区间内电流的功率变换器故障诊断方法。在某相单独励磁区间内,通过另外两相电流传感器输出值之差与前一相输出值的比值,即可快速定位故障器件。所提方法不受电机相数和控制方式限制,控制器负担小,且无需增加额外硬件。仿真和实验验证了方法的有效性。

The power converter is one of the core components of the Switched Reluctance Motor(SRM) speed control system, and it is also the weakest link of system reliability. Aimed at the problems of traditional power converter short-circuit fault diagnosis methods, such as additional hardware, large controller burden, limited diagnosis range, etc., taking the asymmetric half-bridge power converter as the research object, based on the theoretical analysis of the failure modes, the current sensors are rearranged to extract obvious fault feature, and a fault diagnosis method for power converters based on current analysis within a specific rotor position interval is proposed. In the single excitation interval of the current phase, the ratio of the difference between the output values of the other two phases current sensors and the output value of the previous phase can be used to quickly locate the faulty device. This method is not limited by the number of motor phases and control methods, the controller burden is small, and no additional hardware is required. Simulations and experiments verify the effectiveness of this method.