Decoupled Offline Parameter Identification of Induction Motors

Abstract

The offline parameter identification of induction motor can provide solid basis for the design of high dynamic response controllers and observers. However, there exists identification coupling problem among different parameters, especially rotor resistance, leakage inductance, and mutual inductance. To solve this problem, a decoupled offline strategy is proposed for induction motor considering the dynamic model in this paper. First, the rotor resistance and leakage inductance are decoupling identified by high frequency injection method, so as to improve the identification accuracy. Second, the dynamic model is applied for the mutual inductance identification. By injecting the designed symmetrical track current, the influence of inverter nonlinearity and stator resistance can be suppressed, improving the stability and accuracy of mutual inductance identification. The experimental results from a 3. 7kW induction motor drive system verify the effectiveness of the studied identification strategy.