Detection and Compensation Method of BLDC Motor Position Error Using Single Hall Sensor

Abstract

ABSTRACT Detection and Compensation Method of BLDC Motor Position Error Using Single Hall Sensor by Seung Taek OH under the supervision of Professor JU LEE, Ph. D. Department of Electrical Engineering The Graduate School of Hanyang University

Due to the development of motor design and control technology, precise and efficient operation and control of the motor and the reliability of the sensor are becoming important. In order to make a continuous rotor system when the motor is driven, a constant torque should be generated by applying current through the accurate speed and position information of the rotor. To do this, a sensorless method is required to detect the position of the motor by using a position sensor such as an encoder, resolver and Hall sensor, or a signal such as a back electromotive force generated by the rotation of the motor. In order to control the speed and torque of the BLDC motor, the speed and position information of the rotor are absolutely required, and the Hall sensor is used as the position sensor for the 6-step drive. Encoders and resolvers have high resolution and increase the overall system price and size. The Hall sensor has a relatively low resolution but can be manufactured in a small size, has a low price, and has excellent durability due to non-contact type. However, due to the characteristics of the semiconductor device, it is vulnerable to heat and mechanical errors caused by the positioning of the sensor affect the motor performance. If the error is severe, the step can not proceed to the next step and the motor and inverter may be burned out . In this paper, the existing position error method and compensation method are explained, and the disadvantages and limitations are discussed. Based on this, we propose a new error compensation method. First, the three Hall sensor signals are sampled, the reference value is set by ZCP, and the best Hall sensor with the smallest error is selected. Based on the sampled Hall sensor information, we propose a new control algorithm that extracts rotor position information and constructs a 6-step data table with compensated position error. We then apply the proposed algorithm to the simulation and verify its validity.