A thermal management system includes a receiver configured to store a refrigerant fluid; a refrigeration system having a refrigerant fluid path that includes the receiver, and at least one evaporator disposed in the refrigerant fluid path. The refrigeration system is configured to receive the refrigerant fluid from the receiver through the refrigerant fluid path. The at least one evaporator is configured to receive the refrigerant fluid and to extract heat from at least one heat load having a specified thermal inertia that is in at least one of thermal conductive or convective contact with the at least one evaporator.

An air-conditioning apparatus includes a selection unit and a determination unit, the selection unit selecting a reverse-defrosting operation mode or a heating-defrosting simultaneous operation mode, the reverse-defrosting operation mode being a mode in which all of parallel heat exchangers are defrosted by stopping a heating operation, the heating-defrosting simultaneous operation mode being a mode in which each parallel heat exchanger is sequentially defrosted while continuing a heating operation, the determination unit determining whether or not a defrosting operation is to be started, in which the determination unit is configured to start the defrosting operation in a state where the amount of frost deposited on the parallel heat exchangers is smaller in a case where the heating-defrosting simultaneous operation mode is selected than in a case where the reverse-defrosting operation is selected.

Devices, systems, and methods are disclosed for cooling using both air and/or liquid cooling sub circuits. A vapor compression cooling system having both an air and liquid cooling sub circuit designed to service high sensible process heat loads that cannot be solely cooled by either liquid or air is provided.

The pressure reducing device (4) for a cooling system according to the present invention is equipped with: a pressure reducing valve (5) that is disposed in a stage subsequent to a condenser for a refrigerant (40); and a microscopic bubble formation unit (20) that is disposed within the flow path for the refrigerant from the condenser to a heat exchanger so as to form the vapor phase (41) of the refrigerant (40) into microscopic bubbles (41a) and disperse the microscopic bubbles into the liquid phase (42) of the refrigerant.

A method for controlling a vapour compression system, in particular an opening degree of an expansion valve. According to a first control strategy, the expansion valve is closed until the superheat value has increased above a lower threshold superheat value. According to a second control strategy, the expansion valve is kept open until the suction pressure has increased above a lower threshold suction pressure value. In the case of low superheat value as well as low suction pressure, the second control strategy is selected for a limited period of time.

A system for starting a refrigeration system includes a liquid line regulating valve, a liquid line charging valve, a suction line expansion valve, a suction line charging valve, and a controller. The controller is configured to override normal operation of the refrigeration system and transmit a demand signal to enable partial system operation. The controller is configured to operate the liquid line regulating valve and the liquid line charging valve to charge a receiver tank, gradually increase the demand signal to a predetermined level of partial system operation, and release the liquid line charging valve to normal operation. The controller is configured to operate the suction line expansion valve and the suction line charging valve to charge a suction line, gradually increase the demand signal to full system operation, and release the liquid line regulating valve, the suction line expansion valve, and the suction line charging valve to normal operation.

A method for controlling a supply of refrigerant to an evaporator (2) of a vapour compression system (1) is disclosed. During a system identification phase an opening degree (12) of the expansion valve (3) is alternatingly increased and decreased, and a maximum temperature difference, (S.sub.4−S.sub.2).sub.max, between temperature, S.sub.4, of air flowing away from the evaporator (2) and temperature, S.sub.2, of refrigerant leaving the evaporator (2) is determined. During normal operation, the supply of refrigerant to the evaporator (2) is controlled by calculating a reference temperature, S.sub.2,ref, based on the monitored temperature, S.sub.4, and the maximum temperature difference, (S.sub.4−S.sub.2).sub.max, determined during the system identification phase. The supply of refrigerant to the evaporator (2) is controlled in order to obtain a temperature, S.sub.2, of refrigerant leaving the evaporator (2) which is substantially equal to the calculated reference temperature, S.sub.2,ref.

An electronic expansion valve includes: a valve seat, the valve seat has a valve cavity and is provided with a valve port; a valve needle, matching the valve port and used to perform flow adjustment of the electronic expansion valve; a lead screw, forming a floating connection to the valve needle via a barrel portion; and a nut, wherein a threaded fit is formed between the nut and the lead screw, and a lower portion of the nut is provided with a nut guiding portion. A guide component is fixedly connected to the valve seat. The guide component guides both the barrel portion and the valve needle. The electronic expansion valve of the invention is provided with the guide component, and the guide component can guide both the valve needle and the barrel portion, effectively preventing abnormal wear caused by radial deviation of the valve needle and the barrel portion.

An air conditioner unit and method of operating the same includes performing an operating cycle in a feedback control mode, including adjusting the an electronic expansion valve (EEV) to minimize an error between a measured superheat and a target superheat using a PI controller, determining that a target compressor speed has changed by greater than a predetermined speed threshold, and initiating a linear control mode of the operating cycle, including adjusting the EEV using a valve position equation that is a function of the target compressor speed, an indoor temperature, and an outdoor temperature. The controller may also start a transition timer upon initiation of the linear control mode, transition back into a feedback control mode upon expiration of the transition timer, and initialize the integral term of the PI controller based on the EEV position from the linear control mode.

An air conditioner unit and method of operating the same includes performing an operating cycle in a feedback control mode, including adjusting the an electronic expansion valve (EEV) to minimize an error between a measured superheat and a target superheat using a PI controller, determining that a target compressor speed has changed by greater than a predetermined speed threshold, and initiating a linear control mode of the operating cycle, including adjusting the EEV using a valve position equation that is a function of the target compressor speed, an indoor temperature, and an outdoor temperature. The controller may also start a transition timer upon initiation of the linear control mode, transition back into a feedback control mode upon expiration of the transition timer, and initialize the integral term of the PI controller based on the EEV position from the linear control mode.