A cooling device 10 comprising a first evaporation unit 11, a second evaporation unit 12, a first condensation unit 21, a second condensation unit 22, common piping CP, a compressor 30, an expansion valve 40, a first valve 71, and a second valve 72. The common piping CP combines liquid-phase refrigerant LP-COO flowing from the first condensation unit 21 and liquid-phase refrigerant LP-COO flowing from the second condensation unit 22. The first valve 71 adjusts the liquid-phase refrigerant amount LP-COO flowing into the first evaporation unit 11. The second valve 72 adjusts the liquid-phase refrigerant amount LP-COO flowing into the second evaporation unit 12. In addition, the pressure P0 inside the common pipe CP is greater than the respective pressures P1 and P2 inside the first evaporation unit 11 and the second evaporation unit 12. Thus, the length of the piping can be shortened.

Methods and systems for providing control of a heat pump of a motor vehicle are presented. In one operating mode, speed of a heat pump compressor is controlled responsive to an outlet pressure of the heat pump compressor. In a second operating mode, speed of the heat pump compressor is controlled responsive to a pressure ratio between an inlet and an outlet of the heat pump compressor.

A vehicle air conditioning device includes a compressor and a controller. The controller is configured to set an upper limit value of the rotation speed of the compressor based on a combination of whether the speed of the vehicle is lower than a predetermined speed and whether a rotation speed of a fan device for a condenser is lower than a predetermined rotation speed.

The present disclosure relates to the field of air conditioning technology. In particular, it involves a control method and control system based on a variable speed AC compressor.

A method and system for improving energy efficiency of a refrigeration system include system components such as a condenser, one or more expansion valves, an evaporator, one or more compressors, and a system controller electrically coupled to the one or more of the system components, according to one embodiment. The system controller is configured to selectively actuate, directly or indirectly, the one or more expansion valves, the condenser, and/or the one or more compressors, at least partially based on temperatures and/or pressures of the system fluid at various points of the system, to control a temperature of a refrigerated area.

A control system for controlling an output for a plurality of compressors includes a control unit receiving a first value from a first sensor and generating a first output based on the first value. The control unit receives a second value from a second sensor and derives a final output from the first output and the second value. A plurality of compressors receives the control commands from the control unit based on the final output.

A portable system for managing the temperature of a patient during transport includes a heater/cooler configured to be in fluid communication with a heat transfer catheter or a heat transfer surface pad; a pump for circulating heat exchange fluid; an alternating current power supply; and a processor configured to indicate if the alternating current power supply connection to the source of alternating current is interrupted. A rechargeable battery may be configured to provide power to the system when the alternating power supply is not connected to a source of alternating current. If the system is powered on and the connection to the alternating current source is interrupted, the system may automatically switch to receiving power from the rechargeable battery. The processor may alert an operator of the interruption of the connection to the alternating current source and indicate to the operator the amount of energy remaining in the battery.

A vapor compression system includes a compressor, a first heat exchanger, an expansion valve and a second heat exchanger arranged serial refrigerant flow path; a first fan configured to direct air over the first heat exchanger; a controller coupled to the first fan and the compressor, the controller configured to: set a compressor discharge superheat limit; determine a compressor discharge superheat; compare the compressor discharge superheat to the compressor discharge superheat limit; and when the compressor discharge superheat is less than the compressor discharge superheat limit, the controller reducing at least one of a compressor speed and a first fan speed.

A heat pump system includes a refrigerant circuit, at least one compressor, an evaporator, and a controller programmed to defrost the evaporator in a defrost mode, wherein in the defrost mode the controller is programmed to monitor the evaporator to detect frost creation thereon, and reduce the speed of the at least one compressor and/or reduce the number of some, but not all operating compressors of the at least one compressor, if frost creation is detected on the evaporator. In some embodiments, the controller is programmed to defrost the evaporator in a second defrost mode. In the second defrost mode the controller is programmed to monitor the evaporator to detect frost creation thereon, turn off the at least one compressor when frost is detected on the evaporator, and operate a fan to force ambient air over the evaporator to defrost the evaporator.

A battery system for powering a transportable thermal management system for altering or maintaining a patient's body temperature by endovascular and/or external heat exchange.