CONTROL OF PERMANENT MAGNET MOTORS AND GENERATORS

摘要

A permanent magnet motor (2), and also a permanent magnet generator (102) comprising a plurality of phase windings, a control system (16) and a commutation circuit (6) is described. The commutation circuit (6) is operative for controlling a timing of a current supplied to the phase windings in dependence upon an angular position of the permanent magnet motor (2). The control system (16) is operative to supply a current to an individual of the phase windings in a current pulse event occurring within a commutation event. The duration of the current pulse event is less than the duration of the commutation event and the proportion of the commutation event for which the current is supplied to the individual of the phase windings is determined so as to control the speed of the motor (2).