The control section controls the electric motor to be driven such that the number of revolutions becomes equal to the target number of revolutions. If the control section sets the target number of revolutions to a number of revolutions of the electric motor requested by another control section, the control section changes the number of revolutions of the electric motor at an increase rate lower than or equal to the upper limit value of the increase rate or at a decrease rate lower than or equal to the upper limit value of the decrease rate. If the control section sets the target number of revolutions to a number-of-revolutions limit value, which is determined based on the voltage of a vehicle battery, the control section is able to decrease the number of revolutions of the electric motor at a decrease rate exceeding the upper limit value.

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.

Methods, systems, and apparatus for a heating, ventilation and air conditioning (HVAC) system that limits the speed of the compressor to allow for the adoption or use of an internal heat exchanger. The HVAC system includes a compressor configured to drive refrigerant flow and an inverter configured to control a speed of the compressor. The HVAC system includes a first sensor configured to measure a temperature of the inverter and an electronic control unit. The electronic control unit is configured to obtain, from the first sensor, the temperature of the inverter. The electronic control unit is configured to determine a range of speeds for the compressor based on the obtained temperature of the inverter. The electronic control unit is configured to operate the compressor within the determined range of speeds.

A refrigeration cycle device includes a charged-amount determination unit that executes a charged-amount determination to determine whether the refrigeration cycle device is in a refrigerant shortage state or not, a compressor control unit that controls a compressor, and a decompression control unit that controls a throttle opening degree of a decompression device. The charged-amount determination unit determines that the refrigeration cycle device is in the refrigerant shortage state when a heat dissipation capacity of a radiator shows a tendency to decrease in a case where the decompression control unit decreases a throttle opening degree of the decompression device while the compressor control unit operates the compressor.

A refrigeration cycle apparatus includes: an electric compressor that compresses and discharges refrigerant; a heating heat exchanger that heats a fluid by high pressure refrigerant discharged from the electric compressor as a heat source; a decompressor that decompresses the refrigerant flowing from the heating heat exchanger; an evaporator that evaporates the refrigerant decompressed by the decompressor; and a rotational speed controller that controls a rotational speed of the electric compressor. The rotational speed controller is configured to reduce an upper limit value of the rotational speed of the electric compressor in accordance with an increase in a pressure ratio of a high-pressure side refrigerant pressure of refrigerant within a range from a discharge port of the compressor to an inlet side of the decompressor to a low-pressure side refrigerant pressure of refrigerant within a range from an outlet side of the decompressor to a suction port of the compressor.

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.

Disclosed is a system for dynamically mitigating resonance in a transport refrigeration unit (TRU) during a mission, having: a TRU controller configured for operating a TRU engine during the mission according to an operational baseline, and while operating the TRU engine, and contemporaneously performing steps including: obtaining a first set of data that comprises real time measurements from one or more accelerometers installed in the TRU; converting the real measurements to a second set of data that comprises real time shock and vibration data; processing the second set of data in a control loop to determine an updated operational baseline that avoids resonance detected in the first set of data; and operating the TRU engine according to the updated operational baseline.

A refrigeration system may include a compressor, a first heat exchanger, a first working fluid flow path, and a second working fluid flow path. The first heat exchanger receives working fluid discharged from the compressor. The first working fluid flow path may receive working fluid from the first heat exchanger and may include an evaporator and an evaporator control valve that is movable between a first position allowing fluid flow through the evaporator and a second position restricting fluid flow through the evaporator. The second working fluid flow path may receive working fluid from the first heat exchanger and may include a eutectic plate and a plate control valve that is movable between a first position allowing fluid flow through the eutectic plate and a second position restricting fluid flow through the eutectic plate.

A system including mode, engine, and battery modules, where the mode module determines whether to operate in an engine mode or a battery mode based on parameters. The engine module, while operating in the engine mode, runs a compressor at a first speed based on a temperature within a temperature controlled container of a vehicle and permits passage of refrigerant through eutectic plates independent of the temperature. A battery, while in the engine mode, is charged based on power received from an electrical source. The battery module, while operating in the battery mode and based on the temperature, runs the compressor at a second speed and prevents passage of the refrigerant through the eutectic plates. While in the battery mode, the battery is not being charged based on power from a shore power source and the electrical source from which power is received during the engine mode.

A transport refrigeration unit system (26) for cooling a trailer compartment (24) is provided. The transport refrigeration unit system (26) includes an engine for controlling a cooling rate capacity, the engine operable at a nominal high speed and a nominal low speed. Also included is a controller (50) in operative communication with the engine to control an engine speed of the engine. Further included is a user interface (52) in operative communication with the controller (50), the user interface (52) providing a high capacity cooling mode to a user, wherein initiation of the high capacity cooling mode includes the engine operating at a speed greater than the nominal high speed to result in a high capacity cooling rate.