An Effective Approach of Speed Estimation Using Position Detector on Six Step Inverter for Trapezoidal PMSM Drive

The design of an electric drive system using a permanent magnet motor has developed, especially in the application of an electric vehicle (EV) system. The optimal electric drive system cannot be separated from the existence of a reliable speed regulation system. The use of a position sensor in the control system is the main issue to improve the performance of the motor control to support the response of the designed speed control. The position sensors that can be used such as the resolver, encoder, and hall effect can provide information on the rotor position when the motor rotates. The resolver and encoder have a high level of precision. However, both sensors have a relatively high price and high complexity in determining the motor position and speed. In this paper, the proposed system uses the approach of changing or shifting angles detected by the hall effect for the estimate, where each sensor-shift will give a different logic value. Then the estimated motor speed converted into motor revolutions per minute. From the results of the speed estimation experiments carried out, the accuracy of the speed estimation results reached 98% with an average error percentage below 0.5% when compared to a tachometer.