Estimation of Stator Resistance and Temperature Measurement in Induction Motor Using Wavelet Network

To complete induction motor thermal protection, a novel stator resistance estimation approach for stator winding temperature monitoring based on wavelet network and parameter identification is presented. By the use of wavelet network that accurately localizes the characteristics of a signal in the time frequency domains, the occurring instants of the signal change can be identified by the multi-scale representation analysis. The stator and rotor resistance are calculated using mathematical model and the motor speed is estimated by use of wavelet network, and then the temperature is obtained according to the principle that the metal resistance depends on its temperature. The improved least squares algorithm (LSA) transform is used to fulfill the network structure and parameter identification, and then the mapping relationship between the stator voltage, stator current, power factor angle and the rotor speed is determined using the wavelet network. The simulation results demonstrate that the proposed method is effective for temperature monitoring of asynchronous motor.