The modeling of switched reluctance machines with magnetically coupled windings

Abstract

This paper presents a method of modeling switched reluctance motors with strongly coupled windings, such as switched reluctance machines (SRMs) with fully pitched windings or with commutating windings. These machines are particularly difficult to model because, unlike a conventional SRM, the flux linking any one winding of the machine is a nonlinear function of rotor position and all phase currents. The problem is overcome by breaking down the instantaneous flux linkages and currents in each phase to give the flux and magnetomotive force (MMF) in each tooth of the machine. The flux and MMF per tooth can then be linked in the model by a simple lookup table, determined from either simulation or measurement. The paper describes the simulation method in detail and then gives extensive comparisons between measurement and simulation results for an SRM with fully pitched windings, operating over a range of operating conditions. The results presented also serve to give an insight into the method of operation of these rather complex machines.