In some embodiments, an air-cooled ammonia refrigeration system comprises: a plurality of air-cooled condensers, each having a heat exchanger and at least one axial fan and having a first operating state capable of condensing vaporous ammonia to form liquid ammonia; an evaporator coupled to the air-cooled condenser; a subcooler positioned between the air-cooled condenser and the evaporator; a compressor coupled to the evaporator; an oil cooler coupled to the compressor; and a plurality of valves coupled to the plurality of air-cooled condensers and having a first configuration corresponding to the first operating state of the plurality of air-cooled condensers, and a second configuration corresponding to a second operating state of one or more of the plurality of air-cooled condensers such that the one or more of the plurality of air-cooled condensers functions as an evaporator capable of evaporating liquid ammonia to form vaporous ammonia.

A refrigeration cycle device according to the present disclosure includes: a refrigerant circuit including a compressor, a heat-source-side heat exchanger, a first expansion device, and a load-side heat exchanger, refrigerant cycling through the compressor, the heat-source-side heat exchanger, the first expansion device, and the load-side heat exchanger; a plurality of controllers configured to control the refrigerant circuit; a bypass pipe branching from a high pressure pipe on a discharge side of the compressor and connected to a low pressure pipe on a suction side of the compressor; a second expansion device provided to the bypass pipe, and configured to adjust a flow rate of the refrigerant flowing through the bypass pipe; and a plurality of refrigerant coolers provided to the bypass pipe, and configured to cool the plurality of controllers by using the refrigerant the flow rate of which is adjusted by the second expansion device, each of the plurality of refrigerant coolers including a refrigerant cooling pipe and a plate, the refrigerant cooling pipe forming the bypass pipe, the plate being joined between the refrigerant cooling pipe and a controller of the plurality of controllers.

A rotor that gives rotational power to a compressor part that compresses refrigerant has a rotor core in which through-holes through which the refrigerant passes are formed, the through-holes having a cross section with a plurality of forks in a direction away from a rotation axis, a first end plate that covers a first end surface where one end of both end portions of the through-holes of the rotor core closer to the compressor part is formed, and an upper rotor end plate that covers a lower rotor end surface where the other end of the plurality of holes of the rotor core is formed. The first end plate has a first opening portion that causes the through-holes to communicate with an internal space. The upper rotor end plate has an upper opening portion that causes the through-holes to communicate with the internal space. The upper rotor end plate has projection portions that cover tip end portions, which are divided to respective forks, of the through-holes.

A 3000-20000 rpm RS-SR motor (RS-SR) and adjustable speed drive (ASD), with a cooling and lubrication system that is independent of the existing chiller lubrication and refrigerant cooling circuits. Product is configured as a direct replacement for motor, starter (drive), and gearbox solutions historically and currently used by OEM's on chillers. Oil containment and low motor cavity pressure is achieved with Axial Carbon Ceramic seals. Using an inner shell suspended in an outer shell: a coolant path is created, and vibration is abated, as well as meeting pressure vessel requirements. These features enable precise qualification of product independent of the chiller system over range of speeds and loads on a calibrated test stand. Specific information derived from qualification tests enables integration of optimization subroutines into the ASD that improve efficiency and increase ability to operate at or near compressor surge boundary.

A refrigeration system, in particular a transport refrigeration system, comprising: a refrigerant circuit, which in particular works using CO.sub.2 as the refrigerant and in which there is guided a total mass flow of the refrigerant; a high-pressure-side heat exchanger arranged in the refrigerant circuit and cooling refrigerant compressed to a high pressure; at least one cooling stage which expands the principal mass flow from the intermediate-pressure collector to a low pressure in at least one cooling expansion member and in so doing makes refrigeration capacity available at a low-pressure-side heat exchanger; and a refrigerant compressor unit which compresses the principal mass flow from a low pressure to a high pressure, wherein the refrigerant compressor unit has a first compressor stage for compressing, to a medium pressure, the refrigerant of the principal mass flow supplied at low pressure, and a second compressor stage for compressing, to a high pressure, the refrigerant of the principal mass flow that has been compressed to a medium pressure.

A system includes a high side heat exchanger, a flash tank, a first load, a second load, and a thermal storage tank. The high side heat exchanger is configured to remove heat from a refrigerant. The flash tank is configured to store the refrigerant from the high side heat exchanger and discharge a flash gas. The first load is configured to use the refrigerant from the flash tank to remove heat from a first space proximate to the first load. The second load is configured to use the refrigerant from the flash tank to remove heat from a second space proximate to the second load. The thermal storage tank is configured, when a power outage is determined to be occurring, to receive at least a portion of the flash gas from the flash tank, and remove heat from the flash gas.

A heat pump, having: an evaporator for evaporating a working liquid; a liquefier for condensing a compressed working vapor; a compressor motor with a suction mouth having attached thereto a radial impeller to convey a working vapor evaporated in the evaporator through the suction mouth; a guide space arranged to guide a working vapor conveyed by the radial impeller into the condenser; and a cooling device for cooling the guide space or the suction mouth with a liquid, wherein the cooling device is configured to guide the liquid onto an outside of the guide space or of the suction mouth, wherein the outside is not in contact with the working vapor, and wherein an inside of the guide space or of the suction mouth is in contact with the working vapor.

A heat transfer system for controlling two or more heat loads, including a high transient heat load, is provided. The heat transfer system may include sensible-heat thermal energy storage. A method of transferring heat from two or more heat loads to an ambient environment is further provided.

An electric compressor includes a housing, an electric motor, and an inverter. The housing includes a motor chamber. The electric motor includes a stator that includes a stator core, a plurality of first coils, a plurality of second coils, and a plurality of third coils. The first coils are connected in series, the second coils are connected in series, and the third coils are connected in series. One of the first coils that is located electrically closest to the first phase is referred to as a first specific coil, one of the second coils that is located electrically closest to the second phase is referred to as a second specific coil, and one of the third coils that is located electrically closest to the third phase is referred to as a third specific coil. The first to third specific coils are disposed above the shaft center of the drive shaft.

A device includes at least one volume that comprises a liquid quantity of a liquid and a partial volume with a working medium. The device further includes multiple volume limiting elements which limit the at least one volume and which are configured such that one or more passages allow outflow of a maximum of a predetermined partial quantity of the liquid quantity during one or more of a compression period, an expansion period, or a displacement period. The liquid quantity performs a rotation about an axis of rotation. The multiple volume limiting elements are configured to prevent an annular flow of the liquid quantity about the axis of rotation. The at least one volume is changeable in terms of its overall size by displacement of at least one of the volume limiting elements.