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US 11,817,811 B2Granted
Motor controller with power feedback loop
AssigneeAllegro MicroSystems, LLC
InventorYisong Lu
Life of this patent
Estimating the term…
Abstract
A motor control system includes a motor; a motor and a motor control circuit coupled to the motor to provide power to the motor. The motor control circuit includes a power feedback loop having a power reference circuit to provide a reference power level and a power control circuit configured to provide a constant power level to the motor so that the motor operates with a substantially constant power output. The constant power level is proportional to the reference power level. Thus, the motor also provides substantially constant torque when the motor is at a constant speed.
Claims14
A system comprising:
- a motor;
- and
- a motor control circuit coupled to the motor to provide power to the motor, the motor control circuit comprising:
- a power reference circuit to provide a reference power level;
- a first difference circuit that produces a first difference signal being a difference between the reference power level and a power level applied to the motor;
- a power control circuit configured to receive the first difference signal and to provide a substantially constant power level to the motor so that the motor operates with a substantially constant torque at a substantially constant motor speed, wherein the constant power level is proportional to the reference power level;
- and
- a speed feedback loop comprising a second difference circuit that produces a second difference signal being a difference between a reference speed value and a back-electromotive force (EMF) signal, wherein the second difference signal is received at an input of the power reference circuit, wherein the back-EMF signal represents the back-EMF voltage of the motor, wherein the motor is directly coupled to the second difference circuit to provide the back-EMF signal directly to the second difference circuit.
5 more elements
A circuit comprising:
- a motor driver circuit comprising a plurality of switches coupled to provide power to a motor;
- and
- a motor control circuit comprising:
- a power reference circuit to provide a reference power level;
- a first difference circuit that produces a first difference signal being a difference between the reference power level and a power level applied to the motor;
- and
- a power control circuit configured to receive the first difference signal and to control the motor driver circuit to apply a constant power level to the motor so that the motor operates with a substantially constant torque, wherein the constant power level is proportional to the reference power level;
- and
- a speed feedback loop comprising a second difference circuit that produces a second difference signal being a difference between a reference speed value and a back-electromotive force (EMF) signal, wherein the second difference signal is received at an input of the power reference circuit, wherein the back-EMF signal represents the back-EMF voltage of the motor, wherein the motor is directly coupled to the second difference circuit to provide the back-EMF signal directly to the second difference circuit.
6 more elements
Dependencies are inferred from the claim text.