A system for controlling a compressor may include an engine controller controlling a fuel injection amount corresponding to an engine load and an opening amount of a throttle by reflecting a required torque required for an air conditioner, an operation information detector for detecting operation information according to driving state of the vehicle, a compressor generating pressure through a piston operation of a cylinder utilizing the power of the engine during operation of the air conditioner, and a controller determining an engine negative pressure of an intake manifold stored in the brake booster at a value, and when the negative pressure of intake manifold is below a first threshold value when the brake is operated, the engine enters a negative pressure recovery mode for predicting an insignificant negative pressure drop condition that falls below a second threshold value which is the A/C cut control condition and reduces the A/C duty.

A vehicle air conditioning system includes an in-vehicle air conditioner that includes a refrigerant circulation circuit including a compressor and an evaporator; a weather information acquiring section configured to acquire weather information at a current location of a vehicle; an evaporator drying determining section configured to estimate a water retention amount of the evaporator based on the weather information acquired by the weather information acquiring section and an operation state of the in-vehicle air conditioner, and to determine whether the evaporator is in a dry state; and a compressor stop permitting section configured to output a permission signal for permitting stop of the compressor on a condition that the evaporator drying determining section determines that the evaporator is in the dry state.

A heating, ventilation, and air-conditioning (HVAC) system in a hybrid or battery-electric vehicle is provided. The HVAC system includes a compressor that has its own dedicated motor to control its speed. The compressor includes an inlet pressure sensor to determine and output the suction pressure, and an outlet pressure sensor to determine and output the discharge pressure of the compressor. At least one controller can be programmed to determine the discharge-to-suction pressure ratio, and limit the operating speed of the compressor in response to the ratio exceeding a pressure-ratio-threshold. The pressure-ratio-threshold can vary based on ambient air temperature. In the event an inlet pressure sensor is not available, the operating speed of the compressor can be reduced in response to the outlet pressure exceeding an ambient-temperature-based variable threshold.

Systems and methods for heating and cooling a vehicle are disclosed herein. In one embodiment, a method for heating and cooling the vehicle includes: running a compressor of an air-conditioning system; and sensing the temperature inside the cab of the vehicle. The method further includes, closing a path of refrigerant to the compressor by a solenoid valve, pumping-down refrigerant by the compressor, and deactivating the compressor when a lower set point of the temperature inside the cab is reached. The method also includes opening the path of refrigerant to the compressor by a solenoid valve, sensing pressure of refrigerant at an inlet of the compressor by a pressure sensor, and activating the compressor based on a signal from the pressure sensor when an upper set point of temperature inside cab is reached.

In a refrigeration cycle device, a variable throttle mechanism is provided in a refrigerant passage that connects an evaporator and a compressor, and is configured to be capable of changing a passage cross-sectional area of the refrigerant passage. A radiator includes a plurality of tubes and a header tank. The plurality of tubes, through which the refrigerant discharged from the compressor flows, are stacked in a stacking direction. The header tank is provided at an end side in a longitudinal direction of each of the plurality of tubes and communicates with the plurality of tubes. A tank interior space of the header tank is partitioned into a plurality of sections that are arranged in the stacking direction. The header tank includes an opening/closing mechanism configured to open or close a communication portion that causes adjacent ones of the plurality of sections to communicate with each other.

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.

A system is disclosed. The system includes a climate condition determination module that is configured to determine a climate condition associated with a vehicle based upon an external air temperature or a dew point temperature. The system also includes a compressor operational state control module that is configured to control a plurality of operational states of a variable displacement compressor of a heating, ventilation and air conditioning system within the vehicle. The compressor operational state control module is configured to cause the variable displacement compressor to selectively transition from a variable displacement operational state to a fixed displacement-like operational state when the climate condition exceeds a climate threshold to cause an evaporator of the heating, ventilation and air conditioning system to provide evaporator air having an air temperature corresponding to a target evaporator air temperature.

A vehicular air conditioning system includes: a refrigerant circulation line provided with a compressor, an outdoor heat exchanger, an expansion valve and an indoor heat exchanger; and a control unit configured to variably control a rotation speed of the compressor depending on a refrigerant discharge pressure and a refrigerant discharge temperature on an outlet side of the compressor.

This disclosure provides a control method and control system for two or more air-conditioning water chilling units, and air conditioning system. The control method includes: receiving generated by the air-conditioning water chilling units based on a standby condition; determining whether or not two or more standby requests are received; generating standby sequence numbers of the air-conditioning water chilling units according to the standby requests in case where two or more standby requests are received; and closing the air-conditioning water chilling units according to a preset rule based on the standby sequence numbers. When a plurality of air-conditioning water chilling units are used in combination, the control method, control system, and air conditioning system provided by this disclosure can avoid frequent start and stop of the air-conditioning water chilling units, increases the service time of the air-conditioning water chilling units and improves the overall equilibrium control effect.

Provided is a control method on electronic expansion valve in air conditioner, which comprises: obtaining a real-time running frequency of compressor, a real-time exhaust temperature and a real-time outdoor environment temperature as the compressor running; if the air conditioner working in cooling mode, using a first set rule or a second set rule to obtain an integral coefficient in which the selection is based on the comparison of the real-time outdoor environment temperature and a first set outdoor environment temperature; if the air conditioner working in heating mode, using a first set rule or a third set rule to obtain an integral coefficient in which the selection is based on the comparison of the real-time outdoor environment temperature and a second set outdoor environment temperature; performing a PID control on the electronic expansion valve by using an error of the difference between real-time exhaust temperature and a set target exhaust temperature. The method realizes an accurate and stable control on opening amount of electronic expansion valve in air conditioner.