Abstract: A load in an electrical apparatus is driven by two motors M1, M2. Switching means (R1, R2) switches the motors M1, M2 between: a series configuration, in which the motors M1, M2 are connected in series across a power supply and driven with a dc supply; and a parallel configuration in which the motors M1, M2 are connected in parallel across the power supply and driven with an ac supply. In the series configuration, a bridge rectifier BR is switched across the ac supply to provide the dc supply for the motors M1, M2 and in the parallel configuration, the rectifier BR is removed from the circuit. The arrangement can be used to drive a drum of a washing machine or a load in some other kind of appliance.

Abstract: A motor having windings normally energizable by electric power from an AC power supply is stopped in case of an emergency such as a failure of the AC power supply. The motor has a rotor rotatably supported by magnetic bearings out of contact therewith. The windings of the motor are normally energized by a motor driver with the electric power from the AC power supply. When the AC power supply fails, a battery power supply supplies electric power to the windings of the motor to brake the rotor and also to the magnetic bearings to continuously operate the magnetic bearings. A switching controller which includes timers and logic circuit elements controls times to supply the electric power from the battery power supply to the windings of the motor and the magnetic bearings. The switching controller has timers for controlling the times.