Fault Tolerant PM Drive Control for Electric Vehicles with Two Faulted Phase Current Sensors

The detection and correction of phase current sensor faults are very important for reliable operation of the electrical drives for automotive application and avoid dangerous torque oscillations. This paper is focused on the detection and compensation of current offset fault effects in electrical drives based on two current sensors. The main output of the paper is an analytical model of the fault signature of a surface mounted PMSM motor controlled by Field Oriented Control (FOC) strategy based only on two current sensors and the related fault compensation strategy. The model permits to reconstruct all the real motor phase currents and also to estimate the values of the current sensors offsets present in the measured loop. The proposed approach enables fault tolerant control in case of phase current sensor fault. The precision and the performance merit of the method is verified by means of an accurate numerical simulation.