电动汽车一体化驱动系统三相3H桥逆变器的故障相短接容错控制策略

具有车载型充电器的电动汽车拥有相互独立的电机驱动系统与电池充电装置,针对两套装置并不同时工作,成本高、重量大、占据空间资源较大等问题,提出了一种电动汽车驱动与充电一体化的新型拓扑结构,在牵引模式下该一体化拓扑的主要驱动模块等效于一个三相3H桥逆变器。研究该逆变器的电压空间矢量与消除共模电压的控制策略,分析开绕组PMSM在不同坐标系下的数学模型,给出逆变器发生桥臂开关管开路或者短路故障时将故障相短接的重构拓扑与容错控制策略,在转速、电流双闭环控制的基础上,设计"重复控制+PI"的电流内环控制方案,提出一种两相SVPWM控制策略,分析三相2H桥逆变器电压矢量状态切换过程,提出一种改进的七段式两相SVPWM控制策略。仿真和实验结果表明,如果三相3H桥逆变器发生短路故障,一体化系统通过逆变器的拓扑重构,能够实现PMSM系统的良好运行性能。

Tolerant control strategy for 3H bridge inverter short circuitfault of electric vehicle integrated drive system

Electric vehicle ( EV) with onboard type of charger has independent motor drive system and battery charging device. The two devices do not operate at the same time. Aiming at the problem such as high cost, heavy, occupying a larger space resource and other issues, an integrated topology of EV trac-tion system and battery charging system was proposed. The integrated traction mode topology was equiva-lent to a three phase 3H bridge inverter. The voltage space vectors of the inverter and the control strategy of eliminating common mode voltage were studied respectively. The mathematical models in different co-ordinate systems of the open-end windings PMSM were analyzed. The inverter′s reconstruction topology and fault tolerant control strategy were given when some switch short-circuit fault or open-circuit fault and the faulty phase short-circuit connected. On the basis of speed and current double closed-loop control, a synthesized control strategy combined repetitive control with PI control for the proposed system was intro-duced. A five stage two phase SVPWM control strategy was proposed. The switching process and state of the three phase 2H bridge inverter were analyzed. An improved seven stage two phase SVPWM control strategy was proposed. Simulation and experimental results show that, in traction mode of the integrated topology, when short circuit fault occurred, a good operating performance of PMSM system can be a-chieved by the reconstruction of the inverter topology.