A simple method to minimize effects of temperature variation on IPMSM control in real-time manner

This paper proposes a simplified method to minimize the effects of the temperature variation on IPMSM (Interior Permanent Magnet Synchronous Machine) control in a real-time manner especially in vehicle traction applications. Nowadays, normally an IPMSM with a rare-earth magnet is used for HEV traction applications. But because the flux density of the magnet varies with temperature, the optimal operating points, such as MTPA (Maximum Torque Per Ampere) and MTPV (Maximum Torque Per Voltage) of the motor drift according to temperature change. Conventionally, to minimize the effects of the temperature dependence in control, usually flux tables are generated at high, medium and low temperatures. And all the three tables are constructed by experiment, which takes a great deal of time. In this paper, suggested is a simplified way with which the effects of the temperature variations are minimized real-time in control using a flux table at the only one temperature and the back EMF constants according to temperature change. The proposed method is simpler in computation and easier to implement than the conventional.