基于状态反解的开关磁阻电机功率变换器故障诊断

Fault diagnostic for power transistors in power converter of switched reluctance motor drive based on state inverse solution

为提高开关磁阻电机不对称半桥功率变换器可靠性,提出一种基于状态反解的故障诊断方法。首先,在保证系统正常运行的基础上改变传统电流传感器安装位置;其次,根据开关管的故障会导致相电流解算值和真实值出现偏差的特点建立开关管状态求解模型;第三,再利用设定的取舍规则确定开关管真实状态;最后结合开关管驱动信号,通过建立的故障表准确定位故障。研究结果表明:该方案对单相双管故障、多相混合故障均有故障定位能力,有效提升了诊断范围;方案不受电机相数和控制方式的限制,具有较好的通用性。

In order to improve the reliability of asymmetric half bridge power converter of switched reluctance motor drive,a fault diagnosis method based on state inverse solution was proposed.Firstly,on the basis of ensuring the normal operation of the system,the traditional installation position of current sensors was changed.Secondly,according to the characteristics that the fault of transistors will lead to the deviation between the calculated value of phase current and the actual value,the state solution model of transistors was established.Thirdly,a rule of trade-off used to determine the actual state of transistors was determined.Finally,the fault could be accurately located through fault look-up table established by combining with the driving signal of transistors.The results show that the scheme has the fault location ability for single-phase double transistors fault and multiphase mixed fault,which effectively improves the diagnosis ranges,and it is not limited by the number of phases and control mode of system,and has good universality.