Although the conventional DC motor is ideally suited from the control point of view for reversible variable speed applications, it suffers from a number of operational disadvantages, the major ones of which are directly attributable to its commutator and brushes. Not only do the brushes require periodic maintenance, but in low voltage applications (automotive, for example), the voltage drop across the brushes significantly reduces the maximum voltage available for the motor windings. Such disadvantages may be avoided through the usage of a synchronous, or brushless DC, motor. In the brushless DC motor, the rotor field is generated with permanent magnets, and the stator field is generated by sequentially energizing a plurality of stationary windings. In lieu of the brushes and commutator, the brushless DC motor requires a rotor position sensor, additional power electronics, and a logic circuit for suitably energizing the stator windings. In addition, some control device such as an input chopper or a pulse-width-modulation circuit, must be used to control the applied voltage and attain smooth acceleration when starting from zero speed.