Smooth Pole Change Method for Multiphase Induction Motor Drive System

In this study, it is shown that the multiphase IM can be regarded as a superposition of independence, decoupled large-pole and small-pole IM by using the VSD conversion and multiphase IM drive system (IMTS: Induction Motor drive with Transmission System) that actively utilizes pole change is proposed. By deriving a mathematical formula, the factor of torque fluctuation response due to conflict of voltage limiter during pole number change is identified. In addition, the pole change law without torque fluctuation in multiphase IM is proposed by using the formula. An actual machine experiment is also conducted to confirm the effectiveness of the proposed method.