Electric motor chopper control apparatus and method
AssigneeWestinghouse Electric Corp.
InventorsHenry J. Wesling, James H. Franz, Jr.
Life of this patent
Estimating the term…
Abstract
A programmed microprocessor controller chopper apparatus for an electric motor is responsive to an operating condition of the chopper such as at least one of the commutation capacitor charge voltage and the level of motor current for determining the desired commutation circuit operation for that chopper apparatus in relation to the provision of an OFF control pulse in relation to an ON control pulse every cycle of the microprocessor program operation.
Claims10
In control apparatus for a chopper having an ON operation and an OFF operation, said chopper having a commutation capacitor with a charge voltage and being operative to control the energization current of an electric motor, the combination of:
- means for providing a first pulse signal for determining the ON operation of said chopper,
- means for providing a second pulse signal for determining the OFF operation of said chopper,
- means for comparing the actual value of at least one of said charge voltage and said motor current with a predetermined reference value, and
- controlling the time period relationship between said second pulse signal and said first pulse signal to increase the charge voltage when said actual value is less than said predetermined reference value.
In a method of controlling a chopper having an ON operation and an OFF operation to regulate the current of an electric motor, said chopper having a commutation circuit with a charge voltage, the steps of
- sensing an actual operating condition of said chopper comprising one of the motor current and the charge voltage,
- providing an ON control signal for determining the ON operation of the chopper,
- providing an OFF control signal for determining the OFF operation of the chopper,
- comparing said operating condition with a predetermined reference value of said operating condition, and
- controlling the time duration between said OFF control signal and said ON control signal to increase the charge voltage when the actual operating condition is less than said reference value.
Dependencies are inferred from the claim text.