chapter  4
59 Pages

Operational Principles and Modeling of Switched Reluctance Machines

WithBrock Howey, Haoding Li

Due to the effects of magnetic saturation, as well as the non-linear dependence of the flux linkage to rotor position, the machine characteristics must be considered in the modeling of switched reluctance machines (SRM). SRMs have a single source of excitation on the stator. Flux linkage is produced only when the phase coils are excited with current. SRM has a salient structure, which is an essential part of its torque production mechanism. Because of this, SRM characteristics such as flux linkage and torque are functions of rotor position. At the same time, these characteristics are dependent on the phase current. When a stator pole is positioned between two rotor poles, the relative distance between the rotor and stator poles is the largest. The electromagnetic torque can be modeled in a similar manner with constant current excitation at different rotor positions.