Analysis of Alternating Torque of Small Three-Phase Induction Motor Fed by Six-stepped Wave Voltage-Source Inverter and its Investigation

Abstract

First of all, the combined alternating torque of small three phase induction motor fed by six stepped wave voltage-source inverter is analysed by the simplified basic model. The various harmonic components of the combined torque are clarified and shown on the look-up table which are consisted of the stator magnetic field and rotor current. Moreover, the causes of these torques are pointed out.
Secondly, the fundamental equations of the combined toruque which are derived from the basic model are expressed by the equivalent circuit parameters. As a result of the simulation of the fundamental equations, the more pracically simplified equations are derived and also the experiment by the laboratory equipment are performed to evaluate the validity. The simplified equations are satisfied the following items; (1) the higher harmonics below the 17th harmonics are neglected, (2) the only actual effective alternating torque components are calculated.
Finally, as a result of comparision between computation and experiment, we confirmed the validity of the simplified equations.