A novel single switch per phase converter topology for four-quadrant PM brushless DC motor drive

Considerable attention is given to finding compact and low cost converter topologies for permanent magnet brushless motor drives to meet the emerging high volume low performance applications such as in HVAC, air handlers, fans, pumps, small process drives, hand tools, appliance drives and many others in the range of fractional to one hp rating. This paper is concerned with such an attempt to formulate a novel converter topology for a four-quadrant PM brushless DC motor drive. The proposed topology has a single switch per phase limiting the motor drive to half-wave operation. But it also endows unique features with high reliability such as shoot-through free topology by having a switch always in series with a phase winding, operational possibilities even with one or two phase windings failure, reducing the converter losses to half that of the full-wave inverter, reduction of gate drivers and amplifiers, and reduction in logic power supplies requirement. Many of these features result in low cost and compact packaging of the converter for the PM brushless DC motor drive. The machine design modification requirement due to the half-wave operation of the proposed converter is derived in this paper to help in the realization of the proposed motor drive in industrial applications. The formulation and description of the circuit topology and its operation with the motor, their dynamic modeling, simulation and analysis and its comparison to the full-wave inverter fed PMBDC are the key contributions of this paper.