Systems and methods for controlling inducer motor speed
AssigneeCopeland Comfort Control LP
InventorsHarshal Manik Pawar, John F. Broker
Life of this patent
Estimating the term…
Abstract
Disclosed are exemplary embodiments of systems and methods for controlling inducer motor speed. In an exemplary embodiment, a method includes changing stator voltage of an inducer motor (e.g., by changing a firing angle of a triac, using a transistor, a silicon controlled rectifier or semiconductor controlled rectifier (SCR), other switching device, etc.); determining actual inducer motor speed (e.g., by using a hall effect sensor or other speed sensor, etc.); and after determining the actual inducer motor speed, changing the motor stator voltage (e.g., by changing the firing angle of the triac, etc.) to a value at which the actual inducer motor speed is controllably regulated and/or maintained substantially at a set speed.
Claims27
A method of controlling inducer motor speed, the method comprising:
- changing stator voltage of an inducer motor;
- determining actual inducer motor speed;
- and
- after determining the actual inducer motor speed, changing the stator voltage of the inducer motor to a value at which the actual inducer motor speed is controllably regulated and/or maintained substantially at a set speed without substantial speed oscillations;
- wherein after determining the actual inducer motor speed, the method includes:
- determining whether the actual inducer motor speed is greater than a sum of the set speed plus a first delta speed;
- and
- upon determining that the actual inducer motor speed is greater than the sum of the set speed plus the first delta speed, then the method includes reducing the actual inducer motor speed by using a switching device with a higher firing angle to thereby obtain a lower stator voltage for the inducer motor;
- and
- wherein upon determining that the actual inducer motor speed is not greater than the sum of the set speed plus the first delta speed, then the method includes determining whether the actual inducer motor speed is less than a difference of the set speed minus a third delta speed.
A system for controlling inducer motor speed, the system comprising:
- a switching device configured to be operable for changing stator voltage of an inducer motor;
- a speed sensor configured to be operable for determining actual inducer motor speed;
- and
- a control configured to be operable for changing the stator voltage of the inducer motor to a value at which the actual inducer motor speed is controllably regulated and/or maintained substantially at a set speed without significant speed oscillations;
- wherein:
- the control is operable for determining whether the actual inducer motor speed is greater than a sum of the set speed plus a first delta speed;
- and
- upon the control determines that the actual inducer motor speed is greater than the sum of the set speed plus the first delta speed, then the control is operable for reducing the actual inducer motor speed by using the switching device with a higher firing angle to thereby obtain a lower stator voltage for the inducer motor;
- wherein if the control determines that the actual inducer motor speed is not greater than the sum of the set speed plus the first delta speed, then the control is operable for determining whether the actual inducer motor speed is less than a difference of the set speed minus a third delta speed.
Dependencies are inferred from the claim text.