Stator resistance effect in the normalized unified operating point calculation of AC drives for traction application

This paper proposes an analytic method for calculating the steady state operating point of any AC drive, either synchronous or asynchronous, taking into account the effect of the stator resistance. The method uses the 2 nd order curves that represent the voltage, current and torque limits on the normalized id-iq plane. A selection algorithm, able to choose the best operating point for any torque reference, is also given. The method is primarily developed to run on vehicle multi-body simulation software for evaluating the electric drive behavior in any possible operating condition.