吐出過熱度

US10222081(JP, Mitsubishi)
"1. An air-conditioning apparatus comprising:
a plurality of heat source units each including a compressor, a heat source-side heat exchanger, and an accumulator;
a use-side unit including a use-side heat exchanger and a pressure reducing device;
a bypass pipe provided in each of the plurality of heat source units and branched from a pipe between the heat source-side heat exchanger and the pressure reducing device to form a bypass to a suction side of the compressor;
a flow control valve provided in the bypass pipe;
a high-low pressure heat exchanger exchanging heat between low-pressure refrigerant and high-pressure refrigerant, the low-pressure refrigerant flowing through the bypass pipe between the flow control valve and the suction side of the compressor, the high-pressure refrigerant flowing between the heat source-side heat exchanger and the pressure reducing device; and
a controller configured to decide whether liquid refrigerant is unevenly distributed among the plurality of heat source units and to identify a low capacity-side heat source unit and high capacity-side heat source unit, the low capacity-side heat source unit being one of the plurality of heat source units in which the heat source-side heat exchanger has a lower heat exchange capacity, and the high capacity-side heat source unit being another of the plurality of heat source units in which the heat source-side heat exchanger has a higher heat exchange capacity,
wherein after the controller decides that the liquid refrigerant is unevenly distributed among the plurality of heat source units, the controller is configured to adjust a discharge superheating degree of the compressor in the low capacity-side heat source unit to match the lower heat exchange capacity of the heat source-side heat exchanger in the low capacity-side heat source unit with the higher heat exchange capacity of the heat source-side heat exchanger in the high capacity-side heat source unit by adjusting an outlet subcooling degree of the heat source-side heat exchanger or an outlet subcooling degree at a high-pressure outlet of the high-low pressure heat exchanger of the low capacity-side heat source unit,"

圧縮機、熱源側熱交換器およびアキュムレータを備えた複数の熱源機と、

  利用側熱交換器および減圧装置を備えた利用機ユニットと、

  前記熱源機に設けられ、前記熱源側熱交換器と前記減圧装置との配管から分岐して前記圧縮機の吸入側にバイパスするバイパス配管と、

  前記バイパス配管に設けられた流量調整弁と、

  前記バイパス配管において前記流量調整弁と前記圧縮機の吸入側との間を流れる低圧冷媒と、前記熱源側熱交換器と前記減圧装置との間を流れる高圧冷媒との間で熱交換を行う高低圧熱交換器と、

  前記複数の熱源機間で液冷媒の偏在が発生しているか否かを判断し、前記複数の熱源機間で液冷媒の偏在が発生していると判断した際、前記熱源側熱交換器の熱交換能力が高い高能力側熱源機と、前記熱源側熱交換器の熱交換能力が低い低能力側熱源機との前記熱源側熱交換器同士の熱交換能力が、熱交換能力の高い方に一致するように、前記熱源側熱交換器の出口過冷却度または前記高低圧熱交換器の高圧側出口の出口過冷却度と、前記圧縮機の吐出過熱度とを調整する制御装置と

を備えたことを特徴とする空気調和装置。

US2018058740(JP, Mitsubishi)
"4. The refrigeration cycle apparatus of claim 3, wherein the predetermined range has an upper temperature limit of 120 degrees C. and a lower temperature limit at which the refrigerant discharged from the compressor has a degree of superheat of 10 degrees C."

前記予め設定された範囲の上限温度は１２０℃、下限温度は前記圧縮機の吐出過熱度が１０℃となる吐出温度である請求項３記載の冷凍サイクル装置。

US2017370608(JP, Mitsubishi)
"2. The air-conditioning apparatus of claim 1, further comprising
a discharge superheat degree calculation unit configured to calculate a degree of superheat of refrigerant discharged from the compressor,
wherein the liquid refrigerant equalization control is control for regulating the degree of superheat, calculated by the discharge superheat degree calculation unit, of the refrigerant discharged from the compressor of each of the plurality of heat source units to a predetermined value."

前記圧縮機から吐出された冷媒の過熱度を演算する吐出過熱度演算手段を備え、

  前記均液制御は、前記吐出過熱度演算手段で演算された、前記複数の熱源機のそれぞれにおける前記圧縮機から吐出された冷媒の過熱度を、所定値に収束させる制御である請求項１記載の空気調和装置。

US2012297806(JP, Daikin)
"5. The heat pump system according to claim 1, wherein 
said controller being further configured to control said refrigerant circuit to perform overflow prevention control in which said predetermined target degree of superheat is changed so that said degree of superheat increases when a degree of superheat of refrigerant in a discharge of said compressor is less than a predetermined lower limit discharge degree of superheat,
the overflow prevention control being performed with priority over said refrigerant recovery control."

前記制御部（１ａ、１０１ａ、２０１ａ）は、前記圧縮機（２１）の吐出における冷媒の過熱度である吐出冷媒過熱度が所定の下限吐出過熱度よりも小さい場合に、前記冷媒回収制御よりも優先して、前記出口冷媒過熱度が大きくなるように前記目標出口冷媒過熱度を変更するオーバーフロー防止制御を行う、請求項１～４のいずれか１項に記載のヒートポンプシステム（１、１０１、２０１）。

EP2679930(JP, Hitachi)
"[0031] Further, a discharge refrigerant temperature is detected by the discharge-temperature sensor 13 once in every predetermined control time periods, and the opening of the expansion valve 3 is controlled once in every control time periods described as above according to a difference between the discharge refrigerant temperature as sensed and a target discharge temperature dependent on a sensed temperature (an evaporation temperature) of the outdoor heat-exchanger temperature sensor 15, a detection temperature (an outdoor air temperature) of the outdoor temperature sensor 17, the rotational speed of the compressor 1 and the rotational speed command value of the outdoor fan 21. By virtue of this discharge superheat control, control can be implemented such that the suction superheat on the suction side of the compressor 1 is rendered nearly zero, thereby maintaining excellent coefficient of performance of the refrigerating cycle system. "

更に、前記吐出温度センサ１３により吐出冷媒温度を所定の制御時間毎に検出し、この検知された吐出冷媒温度と、室外熱交換器温度センサ１５の検知温度（蒸発温度）、室外温度センサ１７の検出温度（外気温度）、圧縮機１及び室外ファン２１の回転数指令値から決まる目標吐出温度との差に応じて、膨張弁３の開度を上記制御時間毎に制御する。この吐出過熱度制御により、圧縮機１の吸込側の吸込過熱度がほぼゼロになるよう制御され、冷凍サイクル装置の成績係数が良好に保たれる。