Solar photovoltaic -commercial electricity dually driven heat pump system with cold/heat storage

Abstract

A hybrid-driven cold/heat storage type heat pump unit utilizing a solar photovoltaic power and a commercial power, which has a DC compressor ( 2 ) and an AC compressor ( 8 ), is a dual supply heat pump system driven by a solar photovoltaic DC power and a common commercial AC power in combination. When there is sunshine, the DC generated by a solar cell panel ( 60 ) is used for driving the DC compressor ( 2 ) directly to produce cold and heat capacity, and the produced cold and heat capacity could be stored respectively in a phase-change cold storage medium ( 39 ) and a phase-change heat storage medium ( 20 ). When the DC power is insufficient, the AC power from power network is used for power supply.

1 . A solar photovoltaic-commercial electricity dually driven heat pump system with cold/heat storage, characterized by comprising:
 a compressor module including a DC compressor sub-system (A);   a photovoltaic DC power source sub-system (K) for supplying power to said DC compressor sub-system (A);   an air source condenser (D);   a throttle device (G);   an air source evaporator (I);   a heat storage sub-system (C) coupled between said compressor module and said air source condenser (D), wherein said heat storage sub-system (C) contains heat storage phase change material ( 20 ) for absorbing heat from refrigerant;   a cold storage sub-system (H) coupled between said throttle device (G) and said air source evaporator (I), wherein said cold storage sub-system (H) contains cold storage phase change material ( 39 ) for being frozen by said refrigerant;   wherein said compressor module, said heat storage sub-system (C), said air source condenser (D), said cold storage sub-system (H), said throttle device (G), and said air source evaporator (I) form into a loop by pipe lines, for allowing refrigerant to circulate in said loop.   
     
     
         2 . A heat pump system with cold and heat storage of  claim 1 , characterized in the said compressor module further comprises an AC compressor sub-system (B) connected in parallel with the said DC compressor sub-system (A). 
     
     
         3 . A heat pump system with cold and heat storage of  claim 2 , characterized in the four solenoid valves ( 1 ,  3 ,  7 ,  9 ) are provided in said compressor module for controlling the state of connection in said loop of refrigerant circulation of a DC compressor ( 2 ) in said DC compressor sub-system (A) and an AC compressor ( 8 ) in said AC compressor sub-system (B). 
     
     
         4 . A heat pump system with cold and heat storage of  claim 1 , characterized in the
 said heat storage sub-system (C) comprises:
 a heat storage container ( 17 ) with good thermal insulation containing said heat storage phase change material ( 20 ) therein; 
 a first coil heat exchanger ( 23 ) provided within said heat storage container ( 17 ) and being connected in said loop of refrigerant circulation, for allowing refrigerant in said first coil heat exchanger ( 23 ) to exchange heat with said heat storage phase change material ( 20 ); and 
 a second coil heat exchanger ( 26 ) provide in said heat storage container ( 17 ), for allowing water flowing through said second coil heat exchanger ( 26 ) to exchange heat with the heat storage phase change material ( 20 ) inside said heat storage container ( 17 ), 
   said cold storage sub-system (H) comprises:
 a cold storage container ( 38 ) having good thermal insulation, for containing cold storage phase change material ( 39 ); 
 a third coil heat exchanger ( 46 ) provided in said cold storage container ( 38 ) and being connected in said loop of refrigerant circulation, for allowing refrigerant in said third coil heat exchanger ( 46 ) to exchange heat with said cold storage phase change material ( 39 ); and 
 a forth coil heat exchanger ( 43 ) provided in said cold storage container ( 38 ), for allowing water flow through said forth coil heat exchanger ( 43 ) to exchange heat with the cold storage phase change material ( 39 ) in said cold storage container ( 38 ). 
   
     
     
         5 . A heat pump system with cold and heat storage of  claim 1 , characterized by further comprising:
 a first solenoid valve ( 31 ) for bypassing said refrigerant so that said refrigerant does not go through said air source condensor (D);   a second solenoid valve ( 49 ) for bypassing said refrigerant so that said refrigerant does not go through said air source evaporator (I)   wherein each of said first solenoid valve ( 31 ) and said second solenoid valve ( 49 ) is provided in said refrigerant circulation loop.   
     
     
         6 . A heat pump system with cold and heat storage of  claim 5 , characterized by
 a first temperature sensor ( 19 ) is provided in said heat storage sub-system (C) for detecting the temperature of said heat storage phase change material ( 20 ), so as to determine the working statuses of said first solenoid valve ( 31 ); and   a second temperature sensor ( 42 ) is provided in said cold storage sub-system (H) for detecting the temperature of said cold storage phase change material ( 39 ), so as to determine the working statuses of said second solenoid valve ( 49 ).   
     
     
         7 . A heat pump system with cold and heat storage of  claim 1 , characterized in the said heat storage phase change material ( 20 ) can be one selected from paraffin, hydrated salt, and sodium sulfate decahydrate, and said cold storage phase change material ( 39 ) can be one selected from glycerol, water, hydrated salt, and paraffin. 
     
     
         8 . A heat pump system with cold and heat storage of  claim 1 , characterized in that
 a third solenoid valve ( 28 ) for bypassing said refrigerant so that said refrigerant does not go through said heat storage sub-system (C), and   a forth solenoid valve ( 36 ) for bypassing said refrigerant so that said refrigerant does not go through said cold storage sub-system (H),   wherein each of said third solenoid valve ( 28 ) and said forth solenoid valve ( 36 ) is provided in said refrigerant circulation loop.   
     
     
         9 . A heat pump system with cold and heat storage of  claim 1 , characterized in that said photovoltaic DC power source sub-system (K) comprises a solar cell assembly ( 60 ), a junction box ( 59 ), a storage battery ( 58 ), and a power and voltage regulator ( 57 ). 
     
     
         10 . A heat pump system with cold and heat storage of  claim 1 , characterized in that a high pressure sensor ( 4 ) is provided in the high pressure pipe line of said system, a low pressure sensor ( 5 ) is provided in the low pressure pipe line of the system, and safety valves ( 18 ,  47 ) are provided in said heat storage sub-system (C) and said cold storage sub-system (H).