Method and system for detecting a failure in hvac system, and memorizer

Abstract

The invention relates to a method, a system and a storage for detecting a fault of a HVAC system. The method comprises the steps of: obtaining room air temperatures and compressor equivalent runtime during the operation of the HVAC system; calculating a rate of change per unit time of the room air temperatures within the compressor equivalent runtime; and determining whether a fault occurs in the HVAC system based on a change in the rate of change per unit time of the room air temperatures. The invention can be applied to a HVAC system for an on-line fault detection, which is able to effectively detect a series of faculties and may output information such as an alert to help to increase the security and the user satisfaction of the HVAC system.

1 . A method for detecting a fault of an HVAC system, comprising:
 obtaining room air temperatures and compressor equivalent runtime during the operation of the HVAC system;   calculating a rate of change per unit time of the room air temperatures within the compressor equivalent runtime; and   determining whether a fault occurs in the HVAC system based on a change in the rate of change per unit time of the room air temperatures.   
     
     
         2 . The method according to  claim 1 , wherein the room air temperatures are obtained from a temperature controller for controlling the HVAC system. 
     
     
         3 . The method according to  claim 1 , wherein operation data of each compression stage of the HVAC system is obtained from the HVAC system, and the compressor equivalent runtime is obtained by making a calculation based on a capacity ratio of each compression stage. 
     
     
         4 . The method according to  claim 1 , further comprising:
 setting value properties of the rate of change per unit time of the room air temperatures when the HVAC system operates in a cooling mode and a heating mode to be contrary, and distributing along a time axis the rate of change per unit time of the room air temperatures determined as abnormal values, the value properties indicating positive value or negative value;   counting the number of the rate of change per unit time of the room air temperatures distributed on the time axis within a time window, or processing the values of the rate of change per unit time of the room air temperatures within the time window to obtain a processed value; and   determining that a fault has occurred in the HVAC system if the number exceeds a predetermined value or the processed value exceeds a preset value.   
     
     
         5 . The method according to  claim 4 , further comprising:
 outputting report information after the fault is determined to have occurred in the HVAC system.   
     
     
         6 . The method according to  claim 5 , wherein the report information is transmitted to a cloud server via a wireless network, the wireless network comprising Wi-Fi, 4G, BT or ZigBee network. 
     
     
         7 . The method according to  claim 4 , wherein the rate of change per unit time of the room air temperatures is determined as an abnormal value when the value property of the rate of change per unit time of the room air temperatures in the cooling mode or the heating mode is contrary to a set value property, or a difference value between the rate of change per unit time of the room air temperatures and zero is less than a preset value. 
     
     
         8 . A system for detecting a fault of an HVAC system, comprising a processor configured to perform the steps of:
 obtaining room air temperatures and compressor equivalent runtime during the operation of the HVAC system;   calculating a rate of change per unit time of the room air temperatures within the compressor equivalent runtime; and   determining whether a fault occurs in the HVAC system based on a change in the rate of change per unit time of the room air temperatures.   
     
     
         9 . The system according to  claim 8 , wherein the room air temperatures are obtained by the processor from a temperature controller for controlling the HVAC system. 
     
     
         10 . The system according to  claim 8 , wherein operation data of each compression stage is obtained by the processor from the HVAC system, and the compressor equivalent runtime is obtained by the processor by making a calculation based on a capacity ratio of each compression stage. 
     
     
         11 . The system according to  claim 8 , wherein the processor is further configured to perform the steps of:
 setting value properties of the rate of change per unit time of the room air temperatures when the HVAC system operates in a cooling mode and a heating mode to be contrary, and distributing along a time axis the rate of change per unit time of the room air temperatures determined as abnormal values, the value properties indicating positive value or negative value;   counting the number of the rate of change per unit time of the room air temperatures distributed on the time axis within a time window, or processing values of the rate of change per unit time of the room air temperatures within the time window to obtain a processed value; and   determining that a fault has occurred in the HVAC system if the number exceeds a predetermined value or the processed value exceeds a preset value.   
     
     
         12 . The system according to  claim 11 , wherein the processor is further configured to:
 output report information after the fault is determined to have occurred in the HVAC system.   
     
     
         13 . The system according to  claim 12 , wherein the report information is transmitted to a cloud server via a wireless network, the wireless network comprising Wi-Fi, 4G, BT or ZigBee network. 
     
     
         14 . The system according to  claim 11 , wherein the rate of change per unit time of the room air temperatures is determined as an abnormal value when the value property of the rate of change per unit time of the room air temperatures in the cooling mode or the heating mode is contrary to a set value property, or a difference value between the rate of change per unit time of the room air temperatures and zero is less than a preset value. 
     
     
         15 . A storage for storing instructions, when being executed, to implement the method for detecting a fault of a HVAC system according to  claim 1 . 
     
     
         16 . The system according to  claim 11 , wherein the step of processing the values comprises calculating a sum of the values, calculating an arithmetic mean value of the values, or calculating a weighted mean value of the values. 
     
     
         17 . The method according to  claim 4 , wherein the step of processing the values comprises calculating a sum of the values, calculating a arithmetic mean value of the values, or calculating a weighted mean value of the values.