Fault Tolerant SVPWM H-Bridge Drive with Device Short Circuit Protection

This paper proposes the use of H-bridge inverter for feeding a Permanent magnet Synchronous Machine (PMSM) in Electric Vehicle (EV) applications which allows the power transferred from the electrical source to the mechanical load and on the other hand to operate in degraded operating mode even though with one or several phases nonsupplied. In this first an existing method such as three phase inverter by associating fourth extra bridge is connected to the neutral point of the PMSM is presented to operate during degraded modes. Then, an analysis is to differentiate the operation in both normal mode and in degraded mode by using a Space-vector pulse width modulation (SVPWM) control synthesis is carried out for four-leg inverter and H-bridge inverter. Finally, the results are compared and discussed by implementing the control strategies in MATLAB/Simulink. The proposed methods has a considerable reduction of current ripple in case of PMSM stator windings supplied by 3 H-bridges separately. The SVPWM inverter enables to feed the motor with a higher voltage with low harmonic distortions than the conventional sinusoidal PWM inverter.