Influence of power electronics on design of switched reluctance machines

An adjustable speed drive using a doubly salient switched reluctance machine (SRM), because of its ability to operate efficiently from unidirectional winding currents, enables the number of main switching devices in the inverter to be halved, yielding a very economical brushless drive. In general, the SRM is a robust, reliable and almost maintenance free electric drive. The high level performance expected from an adjustable speed drive is not easy to meet, as it is required to accommodate a large number of system nonlinearities in the case of a SRM. Approaches using machine construction aspects making influence on the machine performance becoming more equivalently to efforts at torque control. In this context modern design methods analytical design by a self-prepared design program and simulation of the whole drive system - are presented which allow the examination of essential machine parameters in advance. Target is to find optimal construction parameters of the machine by investigation of single appearances like saturation effects which considerable influence the inverter voltampere requirement. The calculation results show that the SRM can be an attractive alternative to a.c. and d.c. variable speed drives under the condition that the entire drive system is optimally designed and coordinated