Patent ID: 6429614
Filing Date: 2002-08-06
Classification: H02P

Abstract:
A method for driving a motor and for braking the motor running in a reverse rotation direction and for restarting the motor in a preferred rotation direction, the motor being an electronically commutated, polyphase DC motor having winding strands that are connectable to a DC energy source in a preestablished sequence using switching elements that are drivable by an electronic commutation device, the method comprising the steps of:selecting one phase at each time point for each of the directions; detecting a commutation, wherein a voltage in the one phase is induced in a corresponding motor winding and the voltage is compared with a reference voltage; and advancing the one phase and another phase to be commutated by the electronic commutation device by one step in a preestablished sequence after detecting the commutation; wherein, when the motor is rotating in the preferred direction, a constant current-flow angle is established for each phase, and, when the motor is rotating in the reverse direction, markedly varying current-flow angles are established for each phase, which results in a counter-torque opposing the reverse rotation direction depending on a curve of a corresponding induced phase voltage.