Provided is an air conditioning apparatus that is capable of suppressing increases in volume and cost of the apparatus and performing more suitable overheating protection. An electric compressor is an inverter-integrated electric compressor (10) integrally including a compressor (5), an electric motor (6) that drives the compressor (5), and an inverter (7) including a temperature sensor (11) that detects the temperature in the vicinity of a semiconductor switching device, wherein a controller (3) estimates a discharge temperature of the compressor (5) on the basis of a correlation of respective pressure loading characteristics for the detected temperature of the inverter (7), for the rotational speed of the compressor (5), and for the motive force of the compressor (5) in a refrigerating cycle (2).

Included are: a compressor including a compression mechanism that compresses refrigerant, and a motor that drives the compression mechanism; an inverter that applies desired voltage to the motor; an inverter controller that controls the inverter; a high-pressure switch that operates when a discharge pressure of the compressor becomes a preset pressure or higher; and a thermal protector that operates when the temperature of the compressor becomes a preset temperature or higher, wherein the high-pressure switch and the thermal protector are installed on a power supply line for supplying power to the inverter, and the high-pressure switch is opened when the discharge pressure of the compressor becomes the preset pressure or higher, or the thermal protector is opened when the temperature of the compressor becomes the preset temperature or higher, to interrupt power supply to the inverter.

A refrigeration cycle device includes: a compressor having a compression mechanism forming a compression chamber for compressing refrigerant, and a cooled portion cooled by the refrigerant before being compressed by the compression mechanism; a radiator that radiates the refrigerant compressed by the compressor; a decompressor that decompresses the refrigerant radiated by the radiator; an evaporator that evaporates the refrigerant decompressed by the decompressor; an acquisition unit that acquires the state of the refrigerant after cooling the cooled portion and before flowing into the compression chamber; and a control unit that controls the superheat degree of the refrigerant flowing into the compression chamber based on the state of the refrigerant acquired by the acquisition unit.

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.

An inverter control device that controls an inverter unit that converts a DC voltage from a converter unit to an AC voltage and supplies the AC voltage to the DC motor includes a storage unit that stores therein information regarding a synchronization-loss limit; a synchronization-loss limit-current calculation unit that calculates the limitation value on the synchronization-loss limit current on the basis of the magnet temperature of the DC motor, the bus voltage to be applied to the inverter unit, and the information regarding a synchronization-loss limit; and a control unit that compares the primary current to be input to the converter unit with the limitation value and that, when the primary current exceeds the limitation value, outputs an adjustment command to adjust the operating frequency of the DC motor such that the primary current becomes equal to or less than the limitation value.

Provided is an air conditioning apparatus that is capable of suppressing increases in volume and cost of the apparatus and performing more suitable overheating protection. An electric compressor is an inverter-integrated electric compressor integrally including a compressor, an electric motor that drives the compressor, and an inverter including a temperature sensor that detects the temperature in the vicinity of a semiconductor switching device, wherein a controller estimates a discharge temperature of the compressor on the basis of a correlation of respective pressure loading characteristics for the detected temperature of the inverter, for the rotational speed of the compressor, and for the motive force of the compressor in a refrigerating cycle.

A heat pump device includes: a compressor that compresses a refrigerant; a motor that drives the compressor; a wiring switching unit that switches a wiring structure of the motor; an inverter that applies a desired voltage to the motor; and an inverter control unit that generates a PWM signal for driving the inverter, that includes, as an operation mode, a heating operation mode in which a heating operation is performed on the compressor and a normal operation mode in which a refrigerant is compressed by performing a normal operation on the compressor, and that controls a switching operation of the wiring switching unit in accordance with an operation mode.

Systems and methods for lubricant management of a compressor in an HVACR system are disclosed. A heat transfer circuit can utilize a working fluid to provide heating or cooling includes a compressor for compressing the working fluid and a heat source configured to increase a suction temperature of the working fluid entering the compressor. One or more lubricant rheological properties in a compressor system based on measurements taken at or near a bearing cavity of the compressor are determinable. A lubricant reservoir can be in thermal communication with a discharge flow path of the compressor. An internal heat exchanger can be disposed within a compressor for improving viscosity of the lubricant to be cycled back into the compressor. A heater can be located on a fluid line between a lubricant separator and a lubricant inlet. Condenser fans can be controlled.

A heating, ventilation, air conditioning, and/or refrigeration (HVAC&R) system includes a refrigerant loop having a compressor configured to circulate a refrigerant therethrough, a motor configured to drive rotation of the compressor, wherein the motor is a permanent magnet assisted synchronous reluctance (PMASR) motor, and a motor cooling system configured to direct a portion of the refrigerant from the refrigerant loop and through a housing of the PMASR motor to place the portion of the refrigerant in thermal communication with components of the PMASR motor.

A heating, ventilating, and air conditioning (HVAC) system that includes a vapor compression system having a refrigerant, a compressor of the vapor compression system configured to circulate the refrigerant through the vapor compression system, an expansion device of the vapor compression system configured to adjust a flow of the refrigerant through the vapor compression system, and a controller configured to adjust a position of the expansion device based on a measured amount of superheat of the refrigerant entering the compressor, a measured discharge temperature of the refrigerant leaving the compressor, or a combination thereof, such that the measured amount of superheat of the refrigerant entering the compressor reaches a target amount of superheat, the measured discharge temperature of the refrigerant leaving the compressor reaches a target discharge temperature, or a combination thereof.