Inverter fault-tolerant operation of brushless DC motor drives

A novel inverter fault-tolerant control scheme is proposed to drive brushless dc motor (BLDC) based on current character of the traditional six-switch three phases converter BLDC. Analysing a fault-tolerant inverter and its three fault-tolerant schemes (phase A fault-tolerant, phase B fault-tolerant, and phase C fault-tolerant). A general conclusion is drawn that BLDC can be controlled by controlling two faultless phases currents when inverter is faulty. In the proposed strategy, three phase currents are shaped directly by two faultless phases current hysteresis controllers, and the conducting sequence of four power switches is rearranged by four asymmetric voltage vectors. The simulation and experimental results demonstrate the strategy is able to operate stably and continuously with good dynamic performance.