Single-sensor current regulation in switched reluctance motor drives

This paper reports on progress made in the operation of switched reluctance machines with simultaneous excitation of multiple phases using just a single current sensor. This avoids individual current sensors in each motor phase, without compromising the drive performance. A new technique for operation of the classic two-transistor-per-phase power converter with only one current sensor is presented, allowing two phases to be excited simultaneously. The detailed operation and implementation of this technique is shown, together with test results and comparisons with normal operation with one current sensor per phase. The paper concludes that adding a very simple electronic circuit to the existing motor control circuitry allows single-current-sensor operation with uncompromised performance. This is the first time a paper discusses the topic of multiphase switched reluctance motor (SRM) excitation using a minimum number of current sensors.