A cooling device includes a first evaporation unit, a second evaporation unit, a first condensation unit, a second condensation unit, common piping, a compressor, an expansion valve, a first valve, and a second valve. The common piping combines liquid-phase refrigerant flowing from the first condensation unit and liquid-phase refrigerant flowing from the second condensation unit. The first valve adjusts the liquid-phase refrigerant amount flowing into the first evaporation unit. The second valve adjusts the liquid-phase refrigerant amount flowing into the second evaporation unit. In addition, the pressure inside the common pipe is greater than the respective pressures inside the first evaporation unit and the second evaporation unit.

Refrigeration systems and control methods therefor are described. The refrigeration systems include a main circuit to connect, through a pipeline, a multi-stage compressor, a condenser, an economizer, a main throttling element, and an evaporator. An air supply branch is configured to connect to the air outlet of the economizer and the intermediate stage air inlet of the multi-stage compressor. A liquid injection branch is configured to connect to the intermediate stage air inlet of the multi-stage compressor from a section having a high-pressure liquid-phase refrigerant in the main circuit. Through the design of the liquid injection branch, the liquid-phase refrigerant can be introduced when vibration or noise of the unit exceeds a limit. The liquid-phase refrigerant, in the form of droplets, can effectively absorb the sound wave energy in the compressor pipeline to reduce an overall discharge pulsation of the compressor and reduce the noise and vibration of the condenser.

A refrigerant metering system/method incorporating a manual expansion valve (MEV), condenser isolation valve (CIV), flow isolation valve (FIV), and evaporator isolation valve (EIV) is disclosed. The MEV is configured to replace a conventional automated expansion valve (AEV) that controls a refrigerant flow valve (RFV) that is positioned in a heating, ventilation, and air conditioning (HVAC) system between a refrigerant condenser coil (RCC) and a refrigerant evaporator coil (REC) and permits manual metering of refrigerant by the RFV from the RCC to the REC and also allows complete shutoff of refrigerant flow by the RFV from the RCC to the REC. The MEV allows rapid HVAC repair and restoration of service where a replacement AEV is not readily available. The CIV/FIV/EIV are positioned in the refrigerant flow lines to permit the AEV and/or REC to be isolated from HVAC refrigerant flow for repairs to the AEV and/or REC.

A hybrid air handler cooling unit has a bi-modal heat exchanger. In a direct expansion mode or a pumped refrigerant economization mode, the bi-modal heat exchanger is in a refrigerant path in parallel with first and second condenser coils and functions as a condenser coil. In a mixed direct expansion/pumped refrigerant economization mode, the bi-modal heat exchanger is in a refrigerant path in series between an outlet of a pump and an inlet of the first condenser coil and functions as a pre-cooler evaporator coil with return air first flowing across the bi-modal heat exchanger and then across an evaporator coil of an evaporator.

An air conditioner is provided. The air conditioner may include a compressor to compress a refrigerant, at least one oil sensor disposed in the compressor to detect oil stored in the compressor, an oil separator to separate the oil from the refrigerant discharged from the compressor, a first collection tube to collect the oil separated by the oil separator into the compressor, a second collection tube disposed at a height different from a height of the first collection tube, an oil valve disposed in the second collection tube, and a controller to control the oil valve on the basis of information detected by the oil sensor.

A power management method used for power distribution in a transportation refrigeration unit. The power management method includes calculating engine power according to engine operating parameters; calculating power generator real-time input power according to power generator excitation current; calculating available power based on the power generator real-time input power and the engine power; and managing power distributed to a compressor based on the available power. The present invention further relates to a power management system. The power management method and system have the advantages of simplicity, reliability, stable operation and the like, the power generator real-time input power can be calculated according to the power generator excitation current, thus more power can be provided to the compressor on the premise that the power supply to power generator loads is guaranteed, and the operating efficiency of the transportation refrigeration unit is improved.

A compressor includes: a stator core including a plurality of teeth around which an aluminum winding wire is wound in a concentrated manner; a rotor core disposed on an inner diameter side of the stator core and including a plurality of magnet insertion holes; and a plurality of ferrite magnets inserted in the magnet insertion holes, in which when a width of a winding wire portion formed in each of the teeth is represented as A, a length in an axis direction of the stator core is represented as L, and the number of slots is represented as S, the stator core has a shape that satisfies a relation of 0.3<S×A÷L<2.2.

A refrigerant cycle apparatus, that circulates a flammable refrigerant in a refrigerant circuit, includes: a gas-side cutoff valve; a liquid-side cutoff valve, where the gas-side cutoff valve and the liquid-side cutoff valve are disposed on opposite sides of a first portion of the refrigerant circuit; a detection unit that detects refrigerant leakage from the first portion into a predetermined space; and a control unit that sets a cutoff state in the gas-side cutoff valve and the liquid-side cutoff valve when the detection unit detects the refrigerant leakage from the first portion into the predetermined space. The cutoff leakage rate at the gas-side cutoff valve is higher than the cutoff leakage rate at the liquid-side cutoff valve.

A container refrigeration device aims to prevent low temperature damage to freight in a container. The container refrigeration device includes: a temperature controlling section (101) configured to perform, in a switchable manner, first temperature control under which a temperature inside the container (C) is controlled based on a blown air temperature (Tss) and second temperature control under which the temperature inside the container (C) is controlled based on a suction air temperature (Trs) during dehumidification operation; and a control switching section (103) configured to switch the first temperature control to the second temperature control when the blown air temperature (Tss) is higher than the suction air temperature (Trs) during the dehumidification operation in which part of a refrigerant discharged from a compressor (30) is allowed to flow into a reheat heat exchanger (83).

A refrigeration cycle apparatus includes: a first four-way valve having first to fourth ports; a second four-way valve and a third four-way valve each having fifth to eighth ports; a compressor; a discharge pipe connecting a discharge port of the compressor and the first port; a suction pipe connecting a suction port of the compressor and the second port; a first high pressure pipe connecting the discharge pipe and the fifth ports; a second high pressure pipe connecting the third port and the first high pressure pipe; a first valve provided at the first high pressure pipe; a second valve provided at the second high pressure pipe; a low pressure pipe connecting the suction pipe and the sixth ports; a first outdoor heat exchanger connected with the seventh port of the second four-way valve; a second outdoor heat exchanger connected with the seventh port of the third four-way valve; and an indoor heat exchanger connected with the fourth port.