An Online VSI Error Parameter Identification Method for Multiphase IM With Non-Sinusoidal Power Supply

Abstract

Voltage-source-inverter (VSI) nonlinearity compensation is an important scheme for improve motor performance. The traditional off-line method is cumbersome and the compensation effect is poor because it does not simulate the real operation of the motor. To solve this problem, an on-line identification method for compensating multiphase machine based on non-sinusoidal power supply is proposed in this paper. First, a full order air-gap flux observer on harmonic plane was established. Then the voltage error is estimated based on a model reference adaptive system (MRAS) and compensated to the given voltage. In the process of identification, the adaptive law of dead-time voltage is designed, and a feedback gain matrix satisfying Lyapunov stability is also designed. Finally, the feasibility and the effectiveness for harmonic suppression of the proposed method are verified on an experimental platform of a seven-phase induction motor platform.

Keywords

• Multiphase induction motor
• non-sinusoidal power supply
• MRAS
• VSI nonlinearity
• air-gap flux orientation control (AFOC)