Shared switch converter topology for a two phase bipolar drive hybrid stepping motor

Abstract

A converter topology for two phase, bipolar drive hybrid stepping motors using only six power switches is proposed. The two motor phase windings are connected in series to form three nodes so that only six switches are required for controlling the bi-directional current flow in the windings. The control of current in each winding is coupled by the common node. Detailed design of the control strategy which allows PWM current regulation in each phase is developed. The power converter performance is assessed analytically and the proposed system is demonstrated by both simulation and experimental results.