Abstract: A polyphase switched reluctance drive is supplied from a passive power factor correction circuit. The phases of the machine are switched so that there is substantially always one phase drawing current from the DC link and the current drawn from the DC link is substantially always positive. Embodiments of the invention provide a cost-effective, high-power, switched reluctance drive system that draws power at a high power factor from the supply. Corresponding methods provide similar advantages.

Abstract: A converter circuit for an inductive load, such as the phase windings of a switched reluctance motor, uses only n-switches for n-phases. In a four phase machine, each of three of the phases is serially connected with a switch across one voltage source. The remaining phase is serially connected with a switch across another voltage source which receives the inductive energy returned by the other three phases. This returned energy is used to energize the fourth phase. A generator converter is also disclosed in which the energy in the fourth phase is used to provide the excitation for the other three phases.

Abstract: A switched reluctance machine comprises a stator and a rotor and a winding for each phase of the stator. A single current sensor is arranged to sense current in the phase windings such that they are discriminated between according to the energization sequence of the windings by a controller, including a digital processor which counts the sensed currents and attributes the source of the currents counted among the phase windings according to a known phase winding energization sequence.