A refrigeration cycle device includes: a high-pressure side heat exchanger; a low-pressure side heat exchanger; a vehicle-mounted device that supplies heat to the heat medium; a heat-medium air heat exchanger that exchanges heat between the heat medium and air; a switching portion that switches between a state in which the heat medium circulates through the high-pressure side heat exchanger and a state in which the heat medium circulates through the low-pressure side heat exchanger with respect to each of the vehicle-mounted device and the heat-medium air heat exchanger; and a controller that drives the compressor, while controlling an operation of the switching portion to switch to a defrosting mode in which the heat medium circulates between the low-pressure side heat exchanger and the vehicle-mounted device, and the heat medium circulates between the high-pressure side heat exchanger and the heat-medium air heat exchanger, when defrosting of the heat-medium air heat exchanger is necessary.

A vehicular refrigeration cycle unit is a vehicular refrigeration cycle unit installed between a vehicle exterior heat exchanger and a vehicle interior heat exchanger and exchanging heat between secondary refrigerants respectively flowing through the vehicle exterior heat exchanger and the vehicle interior heat exchanger, the vehicular refrigeration cycle unit including: a refrigeration cycle including a compressor, a condenser, an expansion valve, and an evaporator through which a primary refrigerant sequentially flows; an exterior flow passage through which the secondary refrigerant is circulated between the evaporator and the vehicle exterior heat exchanger; an interior flow passage through which the secondary refrigerant is circulated between the condenser and the vehicle interior heat exchanger; a pair of flow passage switching valves connecting the exterior flow passage and the interior flow passage to allow to switch the flow state of the second refrigerant between the exterior flow passage and the interior flow passage; a first bypass flow passage which is installed aside the exterior flow passage and with bypassing the evaporator; and a first flow rate adjustment unit adjusting a flow rate of the secondary refrigerant flowing into the evaporator.

An air conditioning device for vehicle includes a first water-refrigerant heat exchanger, a second water-refrigerant heat exchanger, a first bypass passage, and a second bypass passage. The first bypass passage branches at a point of a coolant passage from a cooling portion of a heating component in the vehicle to the second water-refrigerant heat exchanger, and the first bypass passage is capable of being communicated with the coolant passage at an upstream side of the first water-refrigerant heat exchanger. The second bypass passage bran at a point of the coolant passage from a heater core to the first water-refrigerant heat exchanger, and the second bypass passage is capable of being communicated with the coolant passage at a downstream side of the first water-refrigerant heat exchanger. A part of the first bypass passage which includes a downstream end and a part of the second bypass passage which includes an upstream end are shared.

A system includes a compressor outlet temperature module, a refrigerant quality module, and a correction factor module. The compressor outlet temperature module is configured to estimate a temperature at an outlet of a compressor in a thermal system of an electric vehicle. The refrigerant quality module is configured to estimate a quality of refrigerant at an inlet of the compressor based on an enthalpy at the compressor inlet and an inlet enthalpy correction factor. The refrigerant quality is a ratio of vapor refrigerant mass to total refrigerant mass. The correction factor module is configured to determine the inlet enthalpy correction factor based on the estimated compressor outlet temperature and a temperature measured at the compressor outlet.

An air conditioning system for an electric vehicle includes a refrigerant E-compressor made up of a centrifugal compressor and an electric motor for driving the compressor. The housing of the compressor defines a coolant passage for liquid coolant. A coolant unit pumps liquid coolant through the coolant passage during normal AC system operation to cool the motor. A method for preventing or mitigating harmful effects of liquid refrigerant being ingested by the compressor includes determining whether liquid refrigerant is likely present in the compressor inlet; if so, a heating unit raises the temperature of the liquid coolant to thereby heat and evaporate any liquid refrigerant before starting the compressor. Once the danger of liquid refrigerant is passed, the compressor is started and the heating unit is deactivated.

In a vehicle air conditioning apparatus, during a cooling operation, and a cooling and dehumidifying operation, a refrigerant flows through an outdoor heat exchanger, flows through a supercooling radiator, and then flows into a radiator to absorb heat. During a heating operation, the refrigerant flows through a heat exchanger and then is sucked into a compressor without passing through the supercooling radiator. During a first heating and dehumidifying operation, the refrigerant flows through another radiator, flows through the supercooling radiator, and then flows into another heat exchanger to absorb heat.

A control apparatus for a compressor of a vehicle capable of turning-on/off a compressor based on coolant pressure of an air conditioner in the winter and a method thereof are provided. The control apparatus includes a compressor that is configured to reduce a temperature by compressing a coolant of an air conditioner and a controller that is configured to operate the compressor, to confirm an operation coolant pressure of the air conditioner after operating the compressor. The controller also operates the compressor based on the operation coolant pressure of a measured coolant pressure of the air conditioner when an ambient temperature of the vehicle is less than a reference temperature.

In a vehicle air conditioning apparatus, during a cooling operation, and a cooling and dehumidifying operation, a refrigerant flows through an outdoor heat exchanger, flows through a supercooling radiator, and then flows into a radiator to absorb heat. During a heating operation, the refrigerant flows through a heat exchanger and then is sucked into a compressor without passing through the supercooling radiator. During a first heating and dehumidifying operation, the refrigerant flows through another radiator, flows through the supercooling radiator, and then flows into another heat exchanger to absorb heat.

A cooling device for, for example, a cooling object has a refrigerant circuit with an evaporator, in which a cold air flow for the cooling object exchanges heat with the refrigerant, and a defrosting system for de-icing the evaporator. The defrosting system is controlled according to the degree of icing of the evaporator. The degree of icing of the evaporator is determined by the control unit of the defrosting system on the basis of the temperature of the cold air flow from the cooling object to the evaporator, the temperature and/or the operating pressure of the refrigerant upstream of the evaporator and at least one operating parameter of the compressor.

Methods and systems for assessing operation of a cooling system of an electric vehicle are described. In one example, a super heating temperature at an inlet of a compressor may be generated solely via a temperature sensor and a pressure sensor. The super heating temperature may be compared against a threshold super heating temperature to judge whether or not an amount of refrigerant in the cooling system is as expected.