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 thermal management system, a method of controlling the same, a compressor included in the same in which the thermal management system and the method of controlling the thermal management system determine whether the current state is a low-refrigerant state in which a refrigerant amount is smaller than a reference refrigerant amount on the basis of a degree of superheat or a degree of supercooling detected from a pressure and temperature of a refrigerant when a battery thermal management mode is operated and operations of cooling and heating a vehicle interior do not operate. The compressor is included in the thermal management system and configured as an electric compressor configured to be controlled by the control method. Therefore, it is possible to easily recognize whether the current state is the low-refrigerant state in which the refrigerant amount is smaller than the reference refrigerant amount.

A heat recovery system for an electric vehicle, including first and second switchable heat sources and a controller operable to selectively switch one of the heat sources into thermal communication with a compressor in a thermodynamic cycling system, the thermodynamic cycling system being in thermal communication with a heat sink; and a detector of a temperature differential between each of the switchable heat sources and a fluid entering the compressor; wherein the controller is operable 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 is operable to upgrade low grade heat from the switchable heat source to a higher grade heat upon operation of the compressor.

An air conditioning apparatus includes an electric compressor, an inverter, a temperature detection element, and an ECU. The electric compressor compresses a refrigerant drawn from a refrigerant intake port and discharges the refrigerant from a refrigerant discharge port. The inverter is integrated with the electric compressor so as to be cooled by the drawn refrigerant, and operates the electric compressor according to a control signal. The temperature detection element detects a temperature of the inverter. The ECU outputs a control signal to control the inverter. The ECU performs any one or both of a control for reducing a self-cooling amount of the electric compressor and a control for increasing a self-heat generation amount of the inverter with respect to the inverter when the temperature detected by the temperature detection element is lower than a predetermined reference temperature.

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 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.

A method of controlling an electric compressor, includes aligning a position of a rotor after an electric compressor is powered on; determining whether a refrigerant is in a liquid phase or in a gas phase; preheating the refrigerant by applying power to the electric compressor according to the phase of the refrigerant; and controlling the electric compressor wherein the electric compressor is operated after the refrigerant is preheated.

An electric compressor and a method of controlling the same, the electric compressor including a detection unit for detecting a phase of refrigerant in the electric compressor, a connection unit wound at a position adjacent to a passage of a housing for movement of a refrigerant in the electric compressor, and a control unit for performing control according to the phase of refrigerant by differently controlling power applied to the connection unit in response to data detected by the detection unit. The method including aligning a position of a rotor after an electric compressor is turned on, determining whether a refrigerant is in liquid phase or in gas phase, preheating the refrigerant by applying power to the electric compressor according to the phase of refrigerant, and controlling the electric compressor such that the electric compressor is normally operated after the refrigerant is preheated.

A method for operating a coolant circuit of a refrigeration system of a vehicle having multiple system sections. A single pressure sensor is located in each system section. A temperature sensor is arranged downstream at each component to be balanced in the system sections, such as heat exchangers and a coolant compressor. The sensor signals of the pressure and temperature sensors are supplied to a control unit for the control or regulation of the refrigeration system. Furthermore, a pressure approximation value at the position of the temperature sensor is calculated by a pressure loss value determined using a pressure loss calculation function starting from the position of the pressure sensor arranged in the system section of the component up to the position of the temperature sensor if the temperature sensor and the pressure sensor are arranged at different positions in the system section.

A transport refrigeration unit controllably cools a container, and includes a compressor (58) constructed and arranged compress a refrigerant and a compressor motor (60) configured to drive the compressor (58). A battery (52) of the unit is configured to at least in-part provide electric power to the compressor motor (60). A power management system of the unit includes a computer-based controller configured to generate diagnostic data from data signals received from a battery temperature sensor (122), a battery current sensor (124), and a compressor motor current sensor (126).