A refrigeration system includes a compressor connected to a first heat exchanger and a second heat exchanger. An expansion device is connected between the first heat exchanger and the second heat exchanger. A ratio of a volume of the first heat exchanger to a volume of the second heat exchanger is between 0.6 and 1.8.

An economized refrigeration system includes a main refrigerant circuit having a condenser, an evaporator, an economizer, an expansion device intermediate the condenser and the economizer, and a main compressor fluidly connected by a main refrigerant line. The system also includes an economized refrigerant circuit including an auxiliary compressor system and an auxiliary refrigerant line fluidly connecting the economizer to the auxiliary compressor system and fluidly connecting the main refrigerant line to the auxiliary compressor at a location intermediate the main compressor system and the condenser. The auxiliary compressor system is independently controllable with respect to the main compressor system.

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 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 compressor and a refrigeration device are provided. The compressor has a casing and a main frame disposed in the casing. The main frame has a guide structure configured to position the main frame. By coordination between the guide structure and a tooling, the process for positioning the main frame can be effectively simplified, the efficiency of positioning the main frame can be improved, and the assembly operation by workers can be facilitated.

Embodiments provided herein are directed to systems and methods of re-injecting vaporized flash refrigerant from an economizer into a two-stage compressor. The injection can be through an injection port positioned after the first compression stage. The location of the injection may have a relatively low static refrigerant pressure. The injection port and/or an injection pipe of the economizer may be configured to pre-condition the vaporized flash refrigerant so that a flow velocity and/or direction of the vaporized flash refrigerant flow can be match a flow velocity and/or direction of the refrigerant in the refrigerant conduit.

Systems, apparatus and methods for operating a chiller plant while minimizing or eliminating the occurrence of centrifugal compressor surge. Taking into account chiller design specifications and current operating conditions, a compressor lift point at which surge is predicted to occur is established. Minima and maxima for various chiller setpoints that avoid or eliminate the occurrence of compressor surge are imposed on setpoints provided by a conventional optimizing chiller controller. The chiller system is operated in accordance with the resultant anti-surge setpoints. Coolant tower flow is modulated to enable the compressor to operate at near-surge conditions while preventing the onset of actual surge.

Systems, apparatus and methods for operating a chiller plant while minimizing or eliminating the occurrence of centrifugal compressor surge. Taking into account chiller design specifications and current operating conditions, a compressor lift point at which surge is predicted to occur is established. Minima and maxima for various chiller setpoints that avoid or eliminate the occurrence of compressor surge are imposed on setpoints provided by a conventional optimizing chiller controller. The chiller system is operated in accordance with the resultant anti-surge setpoints. Coolant tower flow is modulated to enable the compressor to operate at near-surge conditions while preventing the onset of actual surge.

A water-based refrigerant for a thermal working machine. The refrigerant for a thermal working machine (150) having an evaporator (A), a condenser (B), a compressor (C.sub.GL), and a throttle element (D). The refrigerant is based on water and comprises a refrigerant component with a hydroxyl group, for example in the form of ethanol. The use of such a mixture as a refrigerant for a thermal working machine and for a thermal working machine having such a refrigerant, and to a method for operating a thermal working machine having such a refrigerant is also disclosed.

A water-based refrigerant for a thermal working machine. The refrigerant for a thermal working machine (150) having an evaporator (A), a condenser (B), a compressor (C.sub.GL), and a throttle element (D). The refrigerant is based on water and comprises a refrigerant component with a hydroxyl group, for example in the form of ethanol. The use of such a mixture as a refrigerant for a thermal working machine and for a thermal working machine having such a refrigerant, and to a method for operating a thermal working machine having such a refrigerant is also disclosed.