General Electric Company

Eric R Benedict

Brian Lee Beifus

David M Erdman

Charles Michael Stephens

Thomas M Jahns

Gerald Burt Kliman

Roger Carlos Becerra

William R Archer

Mark A Brattoli

Wen Liang Soong

Michael W Degner

Robert K Hollenbeck

Glen C Young

Paul Michael Szczesny

Austars R Schnore

A single phase permanent magnet motor includes a rotor, a stator, and a quadrature axis winding positioned out-of-phase from a main winding of the stator for generating an output signal representative of rotor angular position. An integrator can be coupled to the quadrature axis winding for phase retarding the output signal, and a comparator can be coupled to the integrator for detecting zero crossings of the phase retarded output signal to provide a commutation signal. The quadrature axis winding can be positioned about ninety electrical degrees out-of-phase from the main winding of the stator, and the integrator can be adapted to phase retard the output signal by a number of degrees which decreases as a speed of the motor increases. At low speeds the phase retard is preferably at about ninety degrees so that the phase retarded signal becomes in-phase with the main stator winding back EMF voltage. The motor may further include a rectifier coupled to the quadrature axis winding for rectifying the output signal, and a lowpass filter for filtering the rectified output signal to provide a signal proportional to velocity. Also the single phase motor is commutated for maximum torque production.

Quadrature axis winding for sensorless rotor angular position control of

A motor system having a stationary assembly including a winding and a rotatable assembly in magnetic coupling relation to the stationary assembly. A power supply link having upper and lower rails supplied by a power supply provides power to the motor winding. The power supply link has power switches responsive to a motor control signal for selectively connecting the rails to the winding to energize the winding with a motor current whereby an electromagnetic field is produced for rotating the rotatable assembly. The power switches include a set of upper power switches and a set of lower power switches. Each of the power switches has a conducting state and a nonconducting state. The system includes a disable circuit for selectively generating a disable signal and a control circuit for generating the motor control signal to control the power switches. The control circuit is responsive to the disable signal for controlling the power switches so that the lower power switches become conducting and the upper power switches become nonconducting, or vice-versa, thereby de-energizing the winding to disable the motor. Other features are also disclosed including circuitry for commutating the motor in advance of zero crossings of the back electromotive force, correcting asymmetries in the commutation intervals and reversing the motor.

Single phase motor for laundering apparatus

A motor includes a stationary assembly and a rotatable assembly in magnetic coupling relation thereto. The stationary assembly includes a winding, the rotation of the rotatable assembly inducing a back EMF in the winding. A power supply for supplying a voltage across the winding drives a current through the winding. A back EMF sensor connected to the winding generates a back EMF signal representative of the back EMF induced in the winding during periods of time when the voltage is being supplied across the winding. An inverter connected between the power supply and the winding commutates the winding as a function of the back EMF signal, whereby the rotatable assembly rotates. A method of operating the motor and a control circuit for the motor employ the back emf induced in the winding during periods when the voltage is being applied to the winding by the power supply.

Circuit, motor, and method generating a signal representing back EMF in

Growing community of inventors

Madison, WI, United States of America

Eric R Benedict