Back to results
US 9,964,348 B2Granted
Cooling system with low temperature load
AssigneeHeatcraft Refrigeration Products LLC
InventorsMasood Ali, Augusto J. Pereira Zimmermann
Life of this patent
Estimating the term…
Abstract
A system includes a temperature sensor, a pressure sensor, and a controller. The temperature sensor measures a temperature of a refrigerant at a compressor. The compressor receives the refrigerant from a second compressor. The pressure sensor measures a pressure of the refrigerant at the compressor. The controller receives one or more of the measured temperature and the measured pressure and determines that one or more of the measured temperature and the measured pressure exceed a threshold. In response to that determination, the controller actuates a pulse valve coupled to a liquid injection line. The pulse valve controls the flow of a liquid refrigerant from a flash tank through the liquid injection line to mix with the refrigerant at the compressor.
Claims18
An apparatus comprising:
- a temperature sensor configured to measure a temperature of a refrigerant at a first compressor, the first compressor configured to:
- receive the refrigerant from a second compressor;
- and
- send the refrigerant to a high side heat exchanger configured to remove heat from the refrigerant;
- a pressure sensor configured to measure a pressure of the refrigerant at the first compressor;
- and
- a controller communicatively coupled to the temperature sensor and the pressure sensor, the controller configured to:
- receive one or more of the measured temperature and the measured pressure;
- determine whether one or more of the measured temperature and the measured pressure exceed a first threshold;
- in response to a determination that one or more of the received temperature and the received pressure exceed the first threshold, actuate a pulse valve coupled to a liquid injection line, the pulse valve configured to control the flow of a liquid refrigerant from a flash tank through the liquid injection line to mix with the refrigerant at the first compressor;
- determine whether a rate of change of one or more of the measured temperature and the measured pressure is above a second threshold;
- determine whether one or more of the measured temperature and the measured pressure is above a third threshold, the third threshold below the first threshold;
- in response to a determination that the rate of change is above the second threshold and a determination that one or more of the measured temperature and the measured pressure is above the third threshold, initiate closing of a flash gas bypass valve coupled to a flash gas bypass line coupled to the flash tank to restrict the flow of a flash gas through the flash gas bypass line;
- wherein the flash tank is configured to:
- store the refrigerant from the high side heat exchanger;
- and
- send the flash gas through the flash gas bypass line to mix with the refrigerant at the first compressor.
14 more elements
A method comprising:
- measuring a temperature of a refrigerant at a first compressor, the first compressor configured to:
- receive the refrigerant from a second compressor;
- and
- send the refrigerant to a high side heat exchanger configured to remove heat from the refrigerant;
- measuring a pressure of the refrigerant at the first compressor;
- receiving one or more of the measured temperature and the measured pressure;
- determining whether one or more of the measured temperature and the measured pressure exceed a first threshold;
- in response to a determination that one or more of the received temperature and the received pressure exceed the first threshold, actuating a pulse valve coupled to a liquid injection line, the pulse valve configured to control the flow of a liquid refrigerant from a flash tank through the liquid injection line to mix with the refrigerant at the first compressor;
- determining whether a rate of change of one or more of the measured temperature and the measured pressure is above a second threshold;
- determining whether one or more of the measured temperature and the measured pressure is above a third threshold, the third threshold below the first threshold;
- and
- in response to a determination that the rate of change is above the second threshold and a determination that one or more of the measured temperature and the measured pressure is above the third threshold, initiating closing of a flash gas bypass valve coupled to a flash gas bypass line coupled to the flash tank to restrict the flow of a flash gas through the flash gas bypass line;
- wherein the flash tank is configured to:
- store the refrigerant from the high side heat exchanger;
- and
- send the flash gas through the flash gas bypass line to mix with the refrigerant at the first compressor.
13 more elements
A system comprising:
- a temperature sensor configured to measure a temperature of a refrigerant at a first compressor, the first compressor configured to receive the refrigerant from a second compressor;
- a pressure sensor configured to measure a pressure of the refrigerant at the first compressor;
- and
- a controller communicatively coupled to the temperature sensor and the pressure sensor, the controller configured to:
- receive one or more of the measured temperature and the measured pressure;
- determine whether one or more of the measured temperature and the measured pressure exceed a first threshold;
- in response to a determination that one or more of the received temperature and the received pressure exceed the threshold, actuate a pulse valve coupled to a liquid injection line, the pulse valve configured to control the flow of a liquid refrigerant from a flash tank through the liquid injection line to mix with the refrigerant at the first compressor;
- determine whether a rate of change of one or more of the measured temperature and the measured pressure is above a second threshold;
- determine whether one or more of the measured temperature and the measured pressure is above a third threshold, the third threshold below the first threshold;
- and
- in response to a determination that the rate of change is above the second threshold and a determination that one or more of the measured temperature and the measured pressure is above the third threshold, initiate closing of a flash gas bypass valve coupled to a flash gas bypass line coupled to the flash tank to restrict the flow of a flash gas through the flash gas bypass line.
8 more elements
Dependencies are inferred from the claim text.