A vapor compression cooling system includes a centrifugal compressor(s) for compressing a primary fluid in a cycle including at least two compressions, and a control module for controlling the centrifugal compressor dependent upon at least a condition of a secondary fluid. The module controls a power of the centrifugal compressor by adjusting a speed of the motor driving the compressor and/or an opening of guide vanes associated with at least one impeller. The module may also control a pressure drop of a primary fluid moving through at least one expansion device. The at least two compressions may be made in parallel or in series. A related method includes compressing a primary fluid in a first and a second compression cycle and adjusting a parameter of the compressor dependent upon a calculated desired power of the compressor.

An apparatus and a method for controlling a cooling fan of a vehicle are capable of preventing a fan motor from being damaged by locking the fan motor in cold weather conditions. The apparatus includes: a fan motor driving the cooling fan; and a controller generating an operation signal for controlling the cooling fan and providing the operation signal to the fan motor, where the controller confirms an ignition-off time for which an ignition was turned off when the ignition is turned on, confirms a change rate of an air conditioner refrigerant pressure for a measurement time when the ignition-off time exceeds a decision-possible time and an intake air temperature is present within a predetermined temperature, and locks the fan motor depending on the change rate of the air conditioner refrigerant pressure.

A semiconductor device includes a chip stack structure including a first semiconductor chip and a second semiconductor chip stacked on the first semiconductor chip. The first semiconductor chip includes a first substrate, a first circuit layer on a front surface of the first substrate, and a first connecting layer disposed on the first circuit layer and including a first metal pad electrically connected to the first circuit layer. The second semiconductor chip includes a second substrate, a second circuit layer on a front surface of the second substrate, and a second connecting layer disposed on the second circuit layer and including a second metal pad electrically connected to the second circuit layer. The first connecting layer faces the second connecting layer. The first and second metal pads are in contact with each other to couple the first and second semiconductor chips to each other.

A control system for a compressor is provided. The control system includes a controller and first and second control portions. The first control portion is configured to assess an actual temperature of an evaporator and a target temperature of the evaporator and to generate a first compressor speed command signal. The second control portion includes a pressure calibration value and is configured to receive a pressure reading of the climate system, to compare the pressure reading to the pressure calibration value and to generate a second compressor speed command signal. The controller device includes data and is configured to receive the first compressor speed command signal and the second compressor speed command signal and to transmit a control signal to the compressor for causing the compressor to operate at a commanded compressor speed based on the first compressor speed command signal, the second compressor speed command signal, and the data.

A hybrid vehicle, an air conditioning system and a method for controlling the air conditioning system are provided. The air conditioning system includes: an electric compressor; a mechanical compressor, connected with the electric compressor in parallel; a power battery, connected with the electric compressor and configured to supply power to the electric compressor; an engine, connected with the mechanical compressor and configured to supply a power source to the mechanical compressor; an engine controller, connected with the engine and configured to start the engine when the mechanical compressor is to be started; a battery manager, connected with the power battery and configured to detect a state of charge of the power battery; and a controller, connected with the engine controller and the battery manager and configured to start the electric compressor and the mechanical compressor at different time according to the state of charge of the power battery.

A method for operating a refrigeration system for a motor vehicle. The method includes setting an operating mode of the refrigeration system having active primary line and inactive secondary line or having active secondary line and inactive primary line; detecting the pressure in the inactive line; and activating and extraction of refrigerant from the inactive line into the active line by lowering the pressure in the active line to a value below the pressure in the inactive line and by opening the relevant valve device.

A method and system are provided and include determining a sensed condition. When the sensed condition is below a first threshold and above a second threshold, the second threshold being less than the first threshold, a flow of coolant is started in a coolant loop comprising a first portion of a first heat exchanger. A flow of refrigerant is started in a refrigerant loop by starting a compressor within the refrigerant loop at a first speed.

A vapor injection refrigerant system includes a compressor including at least first and second stage inputs, and an output arranged to provide output vapor refrigerant. A condenser is fluidly coupled to the output of the compressor to receive the output vapor refrigerant, and an evaporator is fluidly coupled between the condenser and the first stage input. The evaporator is arranged to provide refrigerant in vapor to the first stage input of the compressor. A chiller is fluidly coupled between the condenser and both the first and second stage inputs. The chiller is arranged to inject refrigerant in vapor form into the first stage input or the second stage input. A bypass branch fluidly couples the output of the compressor to the first stage input of the compressor to provide at least some of the output vapor refrigerant to the first stage input without routing through the condenser, evaporator, and chiller.

A method and system are provided and include determining a sensed condition. When the sensed condition is below a first threshold and above a second threshold, the second threshold being less than the first threshold, a flow of coolant is started in a coolant loop comprising a first portion of a first heat exchanger. A flow of refrigerant is started in a refrigerant loop by starting a compressor within the refrigerant loop at a first speed.