Air conditioner and control method thereof

Abstract

An air conditioner and a control method of an air conditioner are provided. The air conditioner includes an outdoor unit, an indoor unit, a refrigerant circulation loop, and a controller. The controller is configured to determine whether the air conditioner is operating in a cooling mode; obtain a first target supercooling degree in a first standard condition if it determined that the air conditioner is operating stably in the cooling mode; convert a supercooling degree in a current condition into a supercooling degree in the first standard condition; obtain a first refrigerant amount difference according to the first target supercooling degree, the supercooling degree in the first standard condition, an outdoor unit internal volume in the first standard condition, and an outdoor unit internal volume in the current condition; and determine a refrigerant amount of the air conditioner according to the first refrigerant amount difference.

What is claimed is: 
     
         1 . An air conditioner, comprising:
 an outdoor unit;   at least one indoor unit;   a refrigerant circulation loop, the outdoor unit being connected to the at least one indoor unit through the refrigerant circulation loop; and   a controller configured to perform at least one of:   determining whether the air conditioner is operating in one of a cooling mode and a heating mode according to an outdoor ambient temperature, a return air temperature of the indoor unit, and an operating state of the indoor unit;   performing a first refrigerant amount determining mode if it is determined that the air conditioner is operating in the cooling mode, and the air conditioner is operating stably in the cooling mode, the performing the first refrigerant amount determining mode including:
 obtaining a first target supercooling degree in a first standard condition; 
 converting a supercooling degree in a current condition into a supercooling degree in the first standard condition; 
 obtaining a first refrigerant amount difference according to a first corresponding relationship among the first target supercooling degree, the supercooling degree in the first standard condition, an outdoor unit internal volume in the first standard condition, an outdoor unit internal volume in the current condition, and the first refrigerant amount difference; wherein the first refrigerant amount difference is a first relative refrigerant amount calculated based on the first standard condition in the cooling mode; and 
 determining a refrigerant amount of the air conditioner according to the first refrigerant amount difference; 
   or,   performing a second refrigerant amount determining mode if it is determined that the air conditioner is operating in the heating mode, and the air conditioner is operating stably in the heating mode, the performing the second refrigerant amount determining mode including:
 obtaining a second target supercooling degree in a second standard condition; 
 converting a supercooling degree in the current condition into a supercooling degree in the second standard condition; 
 obtaining a second refrigerant amount difference according to a second corresponding relationship among the second target supercooling degree, the supercooling degree in the second standard condition, an indoor unit internal volume in the second standard condition, an indoor unit internal volume in the current condition, and the second refrigerant amount difference; wherein the second refrigerant amount difference is a second relative refrigerant amount calculated based on the second standard condition in the heating mode; and 
 determining the refrigerant amount of the air conditioner according to the second refrigerant amount difference. 
   
     
     
         2 . The air conditioner according to  claim 1 , wherein the controller is further configured to:
 calculate the supercooling degree in the first standard condition according to the supercooling degree in the current condition and a first supercooling degree correction value, in the first refrigerant amount determining mode.   
     
     
         3 . The air conditioner according to  claim 2 , wherein the first supercooling degree correction value is at least related to the outdoor ambient temperature and is any value within a threshold range. 
     
     
         4 . The air conditioner according to  claim 2 , wherein the controller is further configured to:
 calculate a first target refrigerant amount according to the first target supercooling degree, in the first refrigerant amount determining mode; wherein the first target refrigerant amount is greater than or equal to 0;   calculate a refrigerant amount corresponding to the supercooling degree in the first standard condition according to the supercooling degree in the first standard condition; wherein the refrigerant amount corresponding to the supercooling degree in the first standard condition is greater than or equal to 0; and   calculate the first refrigerant amount difference according to the refrigerant amount corresponding to the supercooling degree in the first standard condition, the first target refrigerant amount, the outdoor unit internal volume in the current condition, and the outdoor unit internal volume in the first standard condition.   
     
     
         5 . The air conditioner according to  claim 1 , wherein the controller is further configured to:
 calculate the supercooling degree in the second standard condition according to the supercooling degree in the current condition and a second supercooling degree correction value, in the second refrigerant amount determining mode.   
     
     
         6 . The air conditioner according to  claim 5 , wherein the controller is further configured to:
 calculate the second supercooling degree correction value according to a first constant, a second constant, a third constant, the outdoor ambient temperature, and an indoor ambient temperature; wherein the indoor ambient temperature is an average of the return air temperatures of the indoor unit.   
     
     
         7 . The air conditioner according to  claim 6 , wherein
 the first constant is any value within a first open interval with a lower limit of 2 and an upper limit of 5;   the second constant is any value within a second open interval with a lower limit of 0.1 and an upper limit of 0.5; and   the third constant is any value within a third open interval with a lower limit of −1 and an upper limit of 0.   
     
     
         8 . The air conditioner according to  claim 5 , wherein the controller is further configured to:
 calculate a second target refrigerant amount according to the second target supercooling degree, in the second refrigerant amount determining mode; wherein the second target refrigerant amount is greater than or equal to 0;   calculate a refrigerant amount corresponding to the supercooling degree in the second standard condition according to the supercooling degree in the second standard condition; wherein the refrigerant amount corresponding to the supercooling degree in the second standard condition is greater than or equal to 0; and   calculate the second refrigerant amount difference according to the refrigerant amount corresponding to the supercooling degree in the second standard condition, the second target refrigerant amount, the indoor unit internal volume in the current condition, and the indoor unit internal volume in the second standard condition.   
     
     
         9 . The air conditioner according to  claim 1 , wherein the controller is further configured to:
 determine that the air conditioner is operating in the cooling mode if the outdoor ambient temperature is within a first preset range, the return air temperature of the indoor unit is within a second preset range, and the indoor unit is in a shutdown state; and   determine that the air conditioner is operating in the heating mode if the outdoor ambient temperature is within a third preset range, the return air temperature of the indoor unit is within a fourth preset range, and the indoor unit is in the shutdown state.   
     
     
         10 . The air conditioner according to  claim 1 , wherein the outdoor unit includes a compressor, the at least one indoor unit includes a plurality of indoor units; the controller is further configured to:
 collect an exhaust temperature of the compressor periodically after the air conditioner operates in the cooling mode for a preset duration; and   determine that the air conditioner is operating stably in the cooling mode in a case where a difference between two adjacent exhaust temperatures collected is within a first preset temperature range, a first superheat degree of the indoor unit is greater than a first preset value and lasts for a first period, and a second superheat degree of the indoor unit is less than a second preset value and lasts for a second period;   wherein the first superheat degree of the indoor unit is a minimum value among superheat degrees of the plurality of indoor units; and the second superheat degree of the indoor unit is a maximum value among the superheat degrees of the plurality of indoor units.   
     
     
         11 . The air conditioner according to  claim 1 , wherein the outdoor unit includes a compressor; the controller is further configured to:
 collect an exhaust temperature of the compressor periodically after the air conditioner operates in the heating mode for a preset duration; and   determine that the air conditioner is operating stably in the heating mode in a case where a difference between two adjacent exhaust temperatures collected is within a second preset temperature range.   
     
     
         12 . The air conditioner according to  claim 1 , wherein the controller satisfies one of following:
 that the controller is further configured to output prompt information of abnormal refrigerant amount in a case where the first refrigerant amount difference is outside a first preset refrigerant amount range;   and,   that the controller is further configured to output the prompt information of abnormal refrigerant amount in a case where the second refrigerant amount difference is outside a second preset refrigerant amount range.   
     
     
         13 . A control method of an air conditioner, wherein the air conditioner includes:
 an outdoor unit;   at least one indoor unit;   a refrigerant circulation loop, the outdoor unit being connected to the at least one indoor unit through the refrigerant circulation loop; and   a controller coupled to the outdoor unit, the indoor unit, and the refrigerant circulation loop;   the method comprises at least one of:   determining whether the air conditioner is operating in one of a cooling mode and a heating mode according to an outdoor ambient temperature, a return air temperature of the indoor unit, and an operating state of the indoor unit;   performing a first refrigerant amount determining mode if it is determined that the air conditioner is operating in the cooling mode, and the air conditioner is operating stably in the cooling mode, the performing the first refrigerant amount determining mode including:
 obtaining a first target supercooling degree in a first standard condition; 
 calculating a first target refrigerant amount according to the first target supercooling degree; wherein the first target refrigerant amount is greater than or equal to 0; 
 converting a supercooling degree in a current condition into a supercooling degree in the first standard condition according to the supercooling degree in the current condition and a first supercooling degree correction value; 
 calculating a refrigerant amount corresponding to the supercooling degree in the first standard condition according to the supercooling degree in the first standard condition; wherein the refrigerant amount corresponding to the supercooling degree in the first standard condition is greater than or equal to 0; 
 calculating a first refrigerant amount difference according to the refrigerant amount corresponding to the supercooling degree in the first standard condition, the first target refrigerant amount, an outdoor unit internal volume in the current condition, and an outdoor unit internal volume in the first standard condition; and 
 determining a refrigerant amount of the air conditioner according to the first refrigerant amount difference; 
   or,   performing a second refrigerant amount determining mode if it is determined that the air conditioner is operating in the heating mode, and the air conditioner is operating stably in the heating mode, the performing the second refrigerant amount determining mode including:
 obtaining a second target supercooling degree in a second standard condition; 
 calculating a second target refrigerant amount according to the second target supercooling degree; wherein the second target refrigerant amount is greater than or equal to 0; 
 converting a supercooling degree in a current condition into a supercooling degree in the second standard condition according to the supercooling degree in the current condition and a second supercooling degree correction value; 
 calculating a refrigerant amount corresponding to the supercooling degree in the second standard condition according to the supercooling degree in the second standard condition; wherein the refrigerant amount corresponding to the supercooling degree in the second standard condition is greater than or equal to 0; 
 calculating a second refrigerant amount difference according to the refrigerant amount corresponding to the supercooling degree in the second standard condition, the second target refrigerant amount, an indoor unit internal volume in the current condition, and an indoor unit internal volume in the second standard condition; and 
 determining the refrigerant amount of the air conditioner according to the second refrigerant amount difference. 
   
     
     
         14 . The method according to  claim 13 , wherein the first supercooling degree correction value is at least related to the outdoor ambient temperature and is any value within a threshold range. 
     
     
         15 . The method according to  claim 13 , further comprising:
 calculating the second supercooling degree correction value according to a first constant, a second constant, a third constant, the outdoor ambient temperature, and an indoor ambient temperature; wherein the indoor ambient temperature is an average of the return air temperatures of the indoor unit.   
     
     
         16 . The method according to  claim 15 , wherein the first constant is any value within a first open interval with a lower limit of 2 and an upper limit of 5;
 the second constant is any value within a second open interval with a lower limit of 0.1 and an upper limit of 0.5; and   the third constant is any value within a third open interval with a lower limit of −1 and an upper limit of 0.   
     
     
         17 . The method according to  claim 13 , wherein determining whether the air conditioner is operating in one of the cooling mode and the heating mode according to the outdoor ambient temperature, the return air temperature of the indoor unit, and the operating state of the indoor unit includes:
 determining that the air conditioner is operating in the cooling mode if the outdoor ambient temperature is within a first preset range, the return air temperature of the indoor unit is within a second preset range, and the indoor unit is in a shutdown state; and   determining that the air conditioner is operating in the heating mode if the outdoor ambient temperature is within a third preset range, the return air temperature of the indoor unit is within a fourth preset range, and the indoor unit is in the shutdown state.   
     
     
         18 . The method according to  claim 13 , wherein the outdoor unit includes a compressor, the at least one indoor unit includes a plurality of indoor units; the method further comprises:
 collecting an exhaust temperature of the compressor periodically after the air conditioner operates in the cooling mode for a preset duration; and   determining that the air conditioner is operating stably in the cooling mode in a case where a difference between two adjacent exhaust temperatures collected is within a first preset temperature range, a first superheat degree of the indoor unit is greater than a first preset value and lasts for a first period, and a second superheat degree of the indoor unit is less than a second preset value and lasts for a second period;   wherein the first superheat degree of the indoor unit is a minimum value among superheat degrees of the plurality of indoor units; and the second superheat degree of the indoor unit is a maximum value among the superheat degrees of the plurality of indoor units.   
     
     
         19 . The method according to  claim 13 , wherein the outdoor unit includes a compressor; the method further comprises:
 collecting an exhaust temperature of the compressor periodically after the air conditioner operates in the heating mode for a preset duration; and   determining that the air conditioner is operating stably in the heating mode in a case where a difference between two adjacent exhaust temperatures collected is within a second preset temperature range.   
     
     
         20 . The method according to  claim 13 , further comprising one of following:
 outputting prompt information of abnormal refrigerant amount in a case where the first refrigerant amount difference is outside a first preset refrigerant amount range;   and,   outputting the prompt information of abnormal refrigerant amount in a case where the second refrigerant amount difference is outside a second preset refrigerant amount range.