Improvement of Torque Accuracy of Interior Permanent Magnet Synchronous Motor Considering Temperature Variation

Abstract

Motors used as power source for electrified vehicles require secure of rotors rigidity leading by high-voltage and high-speed technology for miniaturization, large output, and high efficiency. Therefore, most of automobile manufacturers adopt Interior Permanent Magnet Synchronous Motor (IPMSM). Temperature change in Permanent Magnet Synchronous Motor leads to temperature change in permanent magnet which is inserted inside of rotor, and the change occurs into magnetic flux density change depending on the nature of material. Therefore, heat control technique and compensation for reduce power is necessary since the efficiency drop leaded by temperature change in motor of electrified vehicles directly affects power performance and mileage. This paper suggests the way to react to temperature change compensating real-time flux and torque according to motor temperature change using single Look-Up Table (LUT) which is measured at intermediate temperature. Matlab Simulink is used to verify, and Motor Dynamo is used to compare with existing method, and eventually to demonstrate feasibility.