Heat pump apparatus and heat pump control method

Abstract

A heat pump apparatus is provided and includes an outdoor unit, an indoor unit in communication with the outdoor unit, and a control unit in communication with the outdoor unit and the indoor unit. The indoor unit includes a heat exchange housing for heating inlet air, a plurality of temperature sensors to detect and measure temperature of the inlet air and heated air at various positions in the indoor unit, and a control unit to control heat pump operations. The heat exchange housing includes a heat exchanger, a blower, and a heater unit. The control unit includes a processor and a memory, and is configured to perform operations to control a heating operation of the heat pump apparatus based on a calculated temperature of the heated air passing the heat exchanger.

What is claimed is: 
     
         1 . A heat pump apparatus comprising:
 an outdoor unit;   an indoor unit in communication with the outdoor unit that includes:
 a heat exchange housing for heating inlet air that includes:
 a heat exchanger; 
 a blower; and 
 a heater unit; and 
 
 a plurality of temperature sensors to detect and measure temperature of the inlet air and heated air at various positions in the indoor unit; and 
   a control unit that includes a processor and a memory, and is configured to perform operations to control a heating operation of the heat pump apparatus based on a calculated temperature of the heated air passing the heat exchanger.   
     
     
         2 . The heat pump apparatus according to  claim 1 , wherein
 the control unit is configured to perform operations including:   detecting a temperature of the inlet air;   determining a difference between the temperature of the inlet air and a set temperature stored in the memory, wherein   when the difference between the temperature of the inlet air and the set temperature is not greater than or equal to a predetermined temperature stored in the memory, the control unit prevents a heating element contained in the heater unit from heating during a heat pump heating operation.   
     
     
         3 . The heat pump apparatus according to  claim 1 , wherein
 the control unit is configured to perform operations including:   detecting a temperature of the inlet air;   determining a difference between the temperature of the inlet air and a preset inlet air temperature value stored in the memory, wherein   when the difference between the temperature of the inlet air and the preset inlet air temperature value is greater than or equal to a predetermined temperature stored in the memory, the processor further:
 detects a high pressure conversion temperature from a temperature sensor of the outdoor unit; 
 calculates a heat exchanger outlet air temperature; and 
 determines whether or not to perform heat pump heating with the heater unit based on the calculated heat exchanger outlet air temperature. 
   
     
     
         4 . The heat pump apparatus according to  claim 1 , wherein
 the control unit is configured to perform operations including:
 detecting a temperature of the inlet air; 
 detecting a high pressure conversion temperature from a temperature sensor of the outdoor unit; 
 calculating a heat exchanger outlet air temperature; and 
 comparing the calculated heat exchanger outlet air temperature to a preset heat exchanger outlet air temperature value stored in the memory, wherein 
 when the calculated heat exchanger outlet air temperature is greater than or equal to the preset heat exchanger outlet air temperature value stored in the memory, the control unit prevents a heating element contained in the heater unit from heating during a heat pump heating operation. 
   
     
     
         5 . The heat pump apparatus according to  claim 4 , wherein
 when the calculated heat exchanger outlet air temperature is less than or equal to preset heat exchanger outlet air temperature value stored in the memory, the control unit further:   compares an amount of time that has passed since a last operation of the heating element to a preset amount of time stored in the memory such that:
 if the amount of time since the last operation of the heating element exceeds the preset amount of time, the control unit controls the heat pump apparatus to perform heat pump heating with the heater element, and 
 if the amount of time since the last operation of the heating element does not exceed the preset amount of time, the control unit prevents the heating element from heating during a heat pump heating operation. 
   
     
     
         6 . The heat pump apparatus according to  claim 4 , wherein
 the calculated heat exchange outlet air temperature is represented by the formula:   
       
         
           
             
               
                 
                   Tw 
                   ⁢ 
                   2 
                 
                 = 
                 
                   Tk 
                   - 
                   
                     ( 
                     
                       
                         ( 
                         
                           Tk 
                           - 
                           
                             T 
                             
                               w 
                               ⁢ 
                               1 
                             
                           
                         
                         ) 
                       
                       / 
                       
                         exp 
                         ⁡ 
                         ( 
                         
                           KA 
                           / 
                           
                             ( 
                             
                               c 
                               ⁢ 
                               ρ 
                               ⁢ 
                               Q 
                               / 
                               3600 
                             
                             ) 
                           
                         
                         ) 
                       
                     
                     ) 
                   
                 
               
               , 
             
           
         
          where
 c Specific heat of inlet air 
 ρ Density of outlet air 
 Q Air volume 
 Tw1 Inlet air temperature 
 Tw2 Outlet air temperature 
 K Heat passing rate of heat exchanger 
 A Heat transfer area of heat exchanger (fin surface area) 
 Tk Condensing temperature of heat exchanger 
 
       
     
     
         7 . The heat pump apparatus according to  claim 4 , wherein
 the preset heat exchanger outlet air temperature value stored in the memory is set to a predetermined range.   
     
     
         8 . The heat pump apparatus according to  claim 7 , wherein
 the heater unit includes:
 a heater element; 
 a relay that controls the ON/OFF of the heater element; and 
 a safety device that turns OFF the heater element when a temperature of air flowing from the heat exchanger exceeds a predetermined range, and 
   when the calculated heat exchanger outlet air temperature is within the predetermined range, the safety device is prevented from being triggered.   
     
     
         9 . A heat pump heating control method for the heat pump apparatus according to  claim 2 , wherein the control unit performs the operations. 
     
     
         10 . A heat pump heating control method for the heat pump apparatus according to  claim 3 , wherein the control unit performs the operations. 
     
     
         11 . A heat pump heating control method for the heat pump apparatus according to  claim 5 , wherein the control unit performs the operations. 
     
     
         12 . A heat pump heating control method for the heat pump apparatus according to  claim 7 , wherein the control unit performs the operations.