Suction valve pulse width modulation control based on evaporator or condenser pressure
AssigneeCarrier Corporation
InventorsAlexander Lifson, Michael F. Taras
Life of this patent
Estimating the term…
Abstract
A refrigerant system is provided with a suction pulse width modulation valve, and a pulse width modulation control for controlling this valve. System pressures, such as the pressure on the evaporator and the condenser are monitored. The measured system pressures are maintained within a band of acceptable lower and upper limits. As the pulse width modulation control cycles the valve, the refrigerant pressures in the evaporator and the condenser tend to fluctuate. The control ensures those fluctuations are within the limits by controlling the duty cycle of the valve.
Claims21
A refrigerant system comprising:
- a compressor, a condenser downstream of said compressor, an expansion device downstream of said condenser and an evaporator downstream of said expansion device;
- a suction pulse width modulation valve positioned between said evaporator and said compressor;
- and
- a control for selectively operating said suction pulse width modulation valve to deliver refrigerant to said compressor, said control being operable to utilize a pulse width modulation signal to operate the suction pulse width modulation valve, and a duty cycle of said pulse width modulation signal being controlled to control fluctuations in a sensed system pressure.
A refrigerant system comprising:
- a compressor, a condenser downstream of said compressor, an expansion device downstream of said condenser and an evaporator downstream of said expansion device;
- and
- a control for selectively operating a component of said refrigerant system, said control being operable to utilize a pulse width modulation signal to operate the component, and a duty cycle of said pulse width modulation signal being controlled in combination with a sensed system pressure to ensure said sensed system pressure does not fluctuate outside of pre-determined limits.
A method of controlling a refrigerant system comprising the steps of:
- providing a compressor, a condenser downstream of said compressor, an expansion device downstream of said condenser, an evaporator downstream of said expansion device, and a suction pulse width modulation valve positioned between said evaporator and said compressor;
- and
- selectively operating said suction pulse width modulation valve to deliver refrigerant to said compressor, by utilizing pulse width modulation signal to operate the suction pulse width modulation valve, and a duty cycle of said pulse width modulation signal being controlled in combination with a sensed system pressure to ensure said sensed system pressure does not exceed limits of fluctuation.
-16. (canceled)
A refrigerant system comprising:
- a compressor, a condenser downstream of said compressor, an expansion device downstream of said condenser and an evaporator downstream of said expansion device;
- and
- a control for selectively operating a component of said refrigerant system, said control being operable to utilize a pulse width modulation signal to operate the component, and a duty cycle of said pulse width modulation signal being controlled in combination with a sensed system pressure taken on a high pressure side of the refrigerant system to ensure said sensed system pressure is maintained as desired.
Dependencies are inferred from the claim text.