An Optimized Control Method Based on Dual Three-Level Inverters for Open-end Winding Induction Motor Drives

Abstract

An optimized space vector pulse width modulation (SVPWM) method with common mode voltage elimination and neutral point potential balancing is proposed for an open-end winding induction motor. The motor is fed from both of the ends with two neutral point clamped (NPC) three-level inverters. In order to eliminate the common mode voltage of the motor ends and balance the neutral point potential of the DC link, only zero common mode voltage vectors are used and a balancing control factor is gained from calculation in the strategy. In order to improve the harmonic characteristics of the output voltages and currents, the balancing control factor is regulated properly and the theoretical analysis is provided. Simulation and experimental results show that by adopting the proposed method, the common mode voltage can be completely eliminated, the neutral point potential can be accurately balanced and the harmonic performance for the output voltages and currents can be effectively improved.

A New Method for Elimination of Zero-Sequence Voltage in Dual Three-Level Inverter Fed Open-End Winding Induction Motors

“…However, it is only the average value of the zero-sequence voltage that is eliminated while the instantaneous value is still high. The authors of [21] implemented the biasing inverter PWM strategy and the 180° decoupled PWM strategy to eliminate zero-sequence voltage as well as common-mode voltage. However, the instantaneous value is not completely eliminated.…”