New Fault-Tolerant Vector Control of Permanent-Magnet Synchronous Motors with a Rough Resolution Hall-Effect Position Sensor

Abstract

This paper proposes a new fault-tolerant vector control method for permanent-magnet synchronous motors (PMSMs) that are equipped with a set of three Hall-effect sensor (HES) elements. Vector control for PMSMs requires precise rotor position information and gets it from high-resolution position sensors mounted on the rotor such as an encoder and resolver. However, these sensors have several drawbacks in terms of cost, volume, reliability, etc. An HES, which provides very rough position information with a 30-degree error, is a possible candidate for overcoming these drawbacks. This paper proposes a new method that can synthesize position information with sufficient precision for vector control from an HES signal. Even if two of the three HES elements break down, the proposed method allows the PMSM to operate by using the signal from the remaining healthy element.