Active IGBT Temperature Equalization in Field Oriented Control Motor Drives by Magnetic Energy Management

This paper presents an active approach to equalizing the operating temperature of IGBT devices within three-phase inverters used in Field Oriented Control induction motor drives. The proposed approach represents a significant departure from previously developed techniques because managing the magnetic energy stored within the induction machine to periodically reduce the average current circulating across specific IGBTs. A key feature of this approach is its ability to control the operating temperature of the IGBTs of one leg, or even individual IGBTs, while driving the induction motor to deliver the required electromagnetic torque free of fluctuations. After providing an in-depth theoretical analysis of the proposed technique its consistency and dynamic performance are assessed by simulations. By actively equalizing the operating temperature of the six devices of the inverter, the expected mean time between failures can be significantly extended. Although this paper focuses on IGBT -based three-phase inverter