A high efficiency three-phase AC motor drive converter that utilized the neutral point of a motor

This paper exams a three-phase power converter that utilized the neutral point of the motor and demonstrates the motor performance of the proposed converter under various operating conditions. The structure of the proposed circuit is basically consisting of an AC/AC converter (Indirect Matrix Converter (IMC)) and a boost converter that connected to the neutral point of an induction motor. Boost converter will connect to batteries to serve as a secondary input power source of the system. Secondary input power will be injected directly into the DC link voltage of the IMC. In addition, this paper also demonstrates that the DC link voltage of the indirect matrix converter is stable and capable for an additional DC power source connection. Several motor test data such as speed-torque characteristic, torque impact and acceleration-deceleration characteristic are included to confirm the performance of the induction motor. Furthermore, experimental analysis proved that this converter is low loss when controlling with carrier comparison method of either the symmetrical method or the asymmetrical method.