A method of feedthrough and overcurrent protection of a sealed compressor used in a transport climate control system (“TCCS”) is provided. The TCCS includes a climate control circuit with a sealed compressor. The sealed compressor includes an outer housing and an electrical motor within the outer housing. The method includes operating the sealed compressor to compress a working fluid by supplying electrical power to the electric motor of the sealed compressor via a sealed electrical feedthrough in the outer housing of the sealed compressor. The method also includes detecting an operating parameter of the sealed electrical feedthrough, and determining whether the sealed electrical feedthrough is in a melting condition based on the detected operating parameter. Also, the method includes adjusting operation of the climate control circuit upon determining that the sealed electrical feedthrough is in the melting condition until the sealed electrical feedthrough is no longer in the melting condition.

The invention relates to an electric vehicle cabin heating system and a control method. The system comprises a first refrigerant circuit and a second refrigerant circuit that are connected in parallel, wherein the circuits each comprise a gas-liquid separator and a compressor that are connected in series; the first refrigerant circuit further comprises a first expansion unit; the second refrigerant circuit further comprises a second expansion unit and a condenser; and the first expansion unit is connected to the second expansion unit and the condenser in parallel. Thus, rapid cabin heating and stable heating capacity are achieved, the dependence on a heater is eliminated, and an air-conditioning system is simplified. The method comprises: a refrigerant in the second refrigerant circuit undergoing pressure regulation via the second expansion unit and then entering the condenser to release heat for heating a cabin; and a refrigerant in the first refrigerant circuit undergoing throttling and pressure reduction via the first expansion unit and converges with the refrigerant in the second refrigerant circuit in the gas-liquid separator, and the converging refrigerant enters the compressor for cycling. Thus, the decoupling between the regulation of heating capacity and the temperatures and flow rate of exterior ambient air and cabin air is achieved, and the problems of insufficient heating capacity and frequent defrosting of a heat pump system at a low temperature are solved.

A refrigerant circuit system includes a compressor configured to compress refrigerant, a condenser configured to cause the compressed refrigerant to radiate heat, first and second evaporators each configured to decompress and expand the heat-radiated refrigerant by regulating a valve opening degree, first and second evaporators provided in parallel and configured to cause the refrigerant, respectively decompressed and expanded by the first and second expansion valves, to absorb heat, and a controller configured to, based on first information related to a temperature of a first temperature regulated object, regulated by the first evaporator, second information related to a temperature of a second temperature regulated object, regulated by the second evaporator, and third information related to a degree of superheat of the refrigerant at an inlet of the compressor, control the valve opening degrees of the first and second expansion valves and a compression ratio of the refrigerant by the compressor.

A heat pump includes a refrigerant loop. The refrigerant loop includes a first heat exchanger, a first region of a second heat exchanger, a third heat exchanger, a fourth heat exchanger, a compressor, a vapor generator, an accumulator, a first expansion valve, and a first three-way valve. The compressor includes a low-pressure inlet, a mid-pressure inlet, and an outlet. The vapor generator is positioned downstream of the outlet of the compressor and upstream of both the low-pressure inlet and the mid-pressure inlet. The accumulator is positioned immediately upstream of the compressor. The accumulator includes an inlet and an outlet. The first expansion valve is positioned upstream of the accumulator. The first expansion valve includes an inlet and an outlet. The first three-way valve is positioned immediately downstream of the first expansion valve and immediately upstream of the accumulator.

A heat pump air-conditioning system for a vehicle includes a refrigerant circuit, an auxiliary heater, and a control unit. The control unit compares a difference between a target blowout temperature and an actual blowout temperature with a predetermined first temperature threshold value in magnitudes, The control unit adjusts an opening degree of a first expansion valve and an opening degree of a second expansion valve. The control unit adjusts an output power of the auxiliary heater. The control unit executes a plurality of different modes of a heat pump air-conditioning to control the actual blowout temperature to approach and maintain at the target blowout temperature.

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.

An embodiment method for controlling a heating, ventilation, and air conditioning (HVAC) system of a vehicle includes determining a target subcooled temperature of a refrigerant based on a temperature and a pressure of the refrigerant discharged from an outlet of a compressor when the compressor operates, calculating a change in enthalpy of the refrigerant based on the determined target subcooled temperature in a process of condensing and subcooling the refrigerant, calculating a change in enthalpy of air passing over an exterior surface of a condenser based on the calculated refrigerant enthalpy change, and calculating a required fan duty of a cooling fan based on the calculated air enthalpy change, wherein the cooling fan is configured to blow the air to the condenser.

A method for controlling heating of a vehicle thermal management system including an HVAC subsystem may include: determining, by a controller, a target temperature for heating a passenger compartment of a vehicle when the HVAC subsystem operates in heating mode; determining, by the controller, whether an internal temperature of the passenger compartment is lower than the target temperature; adjusting, by the controller, an opening amount of a heating-side expansion valve of the HVAC subsystem to a first opening amount and opening the heating-side expansion valve when the internal temperature is lower than the desired target temperature; and decreasing, by the controller, RPM of a compressor of the HVAC subsystem when the internal temperature is higher than or equal to the desired target temperature. The first opening amount is an opening amount of the heating-side expansion valve with which a heat capacity generated by a heating operation of the HVAC subsystem reaches a maximum heat capacity.

A heat pump system for a vehicle includes an air conditioner circulating a refrigerant through a refrigerant line, a coolant circulation device circulating a coolant through a coolant line, a first chiller connected to the coolant circulation device through the coolant line, connected to the refrigerant line through a first refrigerant connection line, and heat-exchanges a selectively introduced coolant with a refrigerant supplied from the air conditioner to control a temperature of a coolant, and a second chiller connected to the coolant circulation device through the coolant line, connected to a second refrigerant connection line so that a refrigerant is supplied from the air conditioner, and increases a temperature of a refrigerant by heat-exchanging a coolant and a refrigerant so that waste heat is recovered from a coolant selectively flowing thereinto, wherein the air conditioner includes a gas injection part that bypasses some of a refrigerant passing through a condenser to a compressor to increase a flow rate of a refrigerant circulating in the refrigerant line.

An electric valve and a thermal management system. The electric valve comprises a pressure sensing unit. The pressure sensing unit is connected to a valve seat, and the pressure sensing unit can sense the pressure characteristics of a working medium in a detection flow channel) and form a piezoelectric signal. An electric control portion comprises an electric control board. The piezoelectric signal forms, by means of a conditioning circuit, an electrical signal corresponding to a pressure. The electrical signal is used as a part for generating a signal for controlling a driving portion.