Synchronous drive performance of brushless doubly-fed motors

Abstract

Recent studies of the steady-state performance of the brushless doubly fed machine for adjustable speed drive applications are presented. The equivalent circuit and basic performance equations are presented, followed by a proven technique for the solution of the least restrained form of the equations. Model predictions and experimental results are given. It is shown that the machine acts like both a synchronous motor, with power factor adjustable by control winding excitation, and a slip-ring induction machine with slip power recovery and a low power converter rating. The model is suitable for development of control schemes and performance index optimization.<>