Simulation of voltage stress on the inverter fed induction motor winding supplied through feeder cable

In this paper, a method of estimating the voltage distribution among the windings of an inverter-fed induction motor supplied through feeder cable is presented. The inverter-cable-motor model is developed, and the transient analysis is performed using the ATP-EMTP package to estimate the voltage distribution among the motor windings. High frequency parameters which correspond to the rise-time of the PWM wave front are used for the feeder cable and the motor in the ATP model. The high frequency parameters of the induction motor are calculated using field analysis and the parameters of the cable are computed using the Cable Constants routine in the ATP package. Using these parameters, a high frequency equivalent circuit of the inverter-cable-motor model is formed in ATP which is then used to estimate the voltage stresses at the motor terminals and the motor windings. Using this model, the effects of cable on the voltage distribution among the motor winding is analyzed and discussed. In order to check the validity of the model, simulation results are compared with experimental data. The proposed model is a general purpose model and hence can be used for detailed transient analysis with different configurations of the cable and filters