Off-line parameter estimation for the doubly-fed machine

Frequency-domain estimation of the parameters in a d-q representation of the brushless doubly fed machine in the rotor reference frame is investigated using offline techniques. The underlying theory is summarized and simulation results are presented to show that one power-electronic converter operated in the current-source mode can be used to provide sufficient data to estimate all the parameters of the model, including the mutual coupling inductances between the rotor circuit and the two stator circuits. Laboratory results are presented, along with the constraints imposed in the measurement process