Embodiments of the present invention provide a heat recovery system for an electric vehicle (1), comprising first and second switchable heat sources (65, 19) and a control means (20) operable to selectively switch one of the heat sources into thermal communication with a compressor (11) in a thermodynamic cycling system (12), the thermodynamic cycling system being in thermal communication with a heat sink (59, 159); and a detection means (39, 71, T3) operable to detect a temperature differential between each of the switchable heat sources and a fluid entering the compressor; wherein the control means is operable (adapted, arranged) to switch one of the first and second switchable heat sources into thermal communication with the thermodynamic cycling system when a temperature differential is detected between the fluid entering the compressor in the thermodynamic cycling system and the heat available from the switchable heat source, the temperature differential being such that the compressor (11) is operable to upgrade low grade heat from the switchable heat source (65, 19) to a higher grade heat upon operation of the compressor (11).

Embodiments of the present invention provide a refrigerant management system (10) in a heat flux management system (1) for an electric vehicle (150) and a method of refrigerant management, the system comprising a vehicle air conditioning circuit comprising a heat pump circuit (4) with a heating function and a refrigeration cycle refrigerant circuit (6), the air conditioning circuit comprising a heat pump condenser (17) in thermal communication with a heat source (19), a refrigerant evaporator (25) in thermal communication with the heat source (19), an evaporator (31) associated with an expansion valve (29), and a refrigerant compressor (11), wherein the components are fluidly connected to one another by a refrigerant line (9), an accumulator (37) fluidly coupled in the refrigerant line downstream of the heat pump condenser (17), the refrigerant evaporator (25) and evaporator (31) and upstream of the refrigerant compressor (11),

wherein the air conditioning circuit is switchable between a heating mode in which the heat pump circuit (4) is in fluid communication with the compressor (11) and the heat pump condenser (17) is isolated from fluid communication with the compressor (11) and a cooling mode wherein the refrigerant circuit (6) is in fluid communication with the compressor by actuation of at least one valve (15, 21, 41, 47);
wherein the air conditioning circuit comprises a sensor (39) at the compressor inlet (239) operable to monitor refrigerant temperature and pressure; and
wherein when the system is in the heating mode, a shut off valve 41 in line between the heat pump condenser (17) and the accumulator (37) is operable to open to initiate a cold start mode in which a temporary fluid communication is provided between the heat pump condenser (17) and the accumulator in the heat pump circuit when:
the sensor (39) detects one or both of: a superheated refrigerant at the compressor inlet (239) and a temperature gradient of more than 3 Kelvin between ambient (T3) and the compressor inlet (239).

There is disclosed a vehicle air-conditioning device in which a refrigerant subcool degree in a radiator is appropriately controlled, so that comfortable and efficient vehicle interior air conditioning is achievable. The vehicle air-conditioning device executes a heating mode in which a controller lets a refrigerant discharged from a compressor 2 radiate heat in a radiator 4, decompresses the refrigerant by which heat has been radiated by an outdoor expansion valve 6, and then lets the refrigerant absorb heat in an outdoor heat exchanger 7. In the heating mode, the vehicle air-conditioning device controls a refrigerant subcool degree SC of the radiator 4 by the outdoor expansion valve 6. On a basis of a radiator inlet air temperature THin that is a temperature of the air flowing into the radiator 4, the controller corrects a target subcool degree TGSC that is a target value of the refrigerant subcool degree SC in the radiator 4 in a lowering direction, as the radiator inlet air temperature THin rises.

A vehicle temperature management system includes a refrigerant circulation system including a compressor, a first heat exchanger, a depressurization apparatus, a heat exchange plate, a four-way valve, and a second heat exchanger that is configured to heat a first refrigerant that flows to an input port when a management object needs to be cooled through the heat exchange plate, and cool the first refrigerant that flows to the heat exchange plate when the management object needs to be heated through the heat exchange plate.

A vehicle air conditioner is provided which is capable of detecting a refrigerant lack accompanying a refrigerant leakage and the like over time at the earliest possible stage and protecting a compressor. The vehicle air conditioner is provided with a compressor 2, a radiator 4, an outdoor expansion valve 6, and a heat absorber 9. The vehicle air conditioner holds normal time data indicating a relation between the number of revolutions NC of the compressor and a discharge refrigerant temperature Td thereof when a sufficient amount of refrigerant is filled in a refrigerant circuit R. The present invention calculates a discharge refrigerant temperature estimated value Tdst in normal time from the normal time data on the basis of a current number of revolutions NC and compares the discharge refrigerant temperature estimated value Tdst with a current discharge refrigerant temperature Td to determine a refrigerant lack of the refrigerant circuit.

Disclosed is a heat pump system for an electric vehicle including an outdoor fan configured to blow air to an outdoor heat exchanger, a coolant temperature sensor installed at a coolant line and configured to detect a temperature of a coolant circulating in a power train module or a battery, an outdoor heat exchange sensor installed on one side of the outdoor heat exchanger and configured to detect an outdoor heat exchanger outlet pressure defined as a pressure of a refrigerant passing through the outdoor heat exchanger, and a compressor inlet sensor installed on an intake side of a compressor and configured to detect a compressor inlet temperature defined as a temperature of the refrigerant flowing into the compressor. Whether frost sticking occurs may be determined based on information detected by the coolant temperature sensor, the outdoor heat exchange sensor, and the compressor inlet sensor.

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.

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 method for controlling a refrigeration system of a vehicle includes a circuit containing a refrigerant, a compressor, and first and second evaporators which are connected in parallel to the compressor, and a first expansion valve arranged upstream the first evaporator that regulates a pressure drop of the refrigerant before the first evaporator, and a second expansion valve arranged upstream the second evaporator that regulates a pressure drop of the refrigerant before the second evaporator, and a condenser arranged downstream the compressor between the compressor and the first and second expansion valves. The method includes controlling a total opening of the first expansion valve and the second expansion valve, based on a temperature and a pressure of the refrigerant which refrigerant temperature and refrigerant pressure are measured downstream the first and second evaporators at a position between the first and second evaporators and the compressor.

A heat pump system control method for a vehicle includes a process (A) of operating a compressor of an air conditioner to cool or heat an interior of the vehicle while the vehicle is driving, measuring by a controller initial states of the compressor and a refrigerant based on data detected from a data detector, and monitoring the compressor, a process (B) of determining by the controller whether a current coil temperature of a motor unit provided in the compressor is higher than a coil specification temperature through the process (A) and operating a protection mode; and a process (C) of, when the process (B) is completed, calculating by the controller a slope of a coil temperature of the motor unit over time, determining whether the temperature slope is greater than zero (0) three times consecutively to stop the operation of the compressor, and terminating control.