Revolution rate control for DC universal motor, involves regulating field winding current to level lower than current through armature by branching between armature and field winding

摘要

The method involves regulating the motor's operating voltage from an intermediate circuit voltage (+HV), using a first switching arrangement (6). The current through the motor's field winding (1) is regulated to a level lower than the current through the motor's armature (2). The current through the armature can be branched between the armature and the field winding so that only part of the current through the armature flows through the field winding : An independent claim is also included for a circuit for revolution rate control of DC universal motors.