Position Sensorless Control for BLDC Motor for Powertrain Applications

Abstract

Electric vehicle (EV), being a solution to the increased environmental pollution and sound pollution, coming to mainstream use as a passenger vehicle. Permanent magnet motors are being used extensively in EV powertrains. Brush Less DC motor (BLDC) is one of the prime choices. BLDC gives higher power density compared to the Permanent Magnet Synchronous Motor (PMSM). Rotor position sensors, usually hall sensors, are required in BLDC motors for their operation, whether it is starting or running. The problem associated with the use of a rotor position sensor is that the failure will affect the operation of the machine. Using such a vulnerable system in an EV on a fast-moving highway will result in a fatal accident. So in this paper, a position sensorless controller for BLDC motor which is controlled by Field Oriented Control (FOC) is discussed. A comparison of normal FOC and sensorless control is also presented. To showcase the effectiveness of the proposed method in EV applications, the method is tested against some well-known driving cycle scheme such as WLTC Class 3 and UDDS drive cycles.