Reliability Evaluation Model Of Household Inverter Air Conditioning Based On Load Of Building Envelope And Its Application

Reliability is an important indicator to measure product quality.Evaluating whether the designed and manufactured air conditioners meet the expected usage goals,as well as making scientific decisions on air conditioning warranty and operation and maintenance,requires reliability prediction and evaluation.However,the existing research on reliability prediction and evaluation of household variable frequency air conditioners mainly focuses on the level of components,while research on the entire machine is relatively lacking.In view of the shortcomings of existing research,this paper takes a type of household variable frequency air conditioner applied in Chinese Mainland as the object,and carries out the following research work:Firstly,the related factors that affect the reliability of components and their geographical clustering are studied.According to the type of component reliability influencing factors,the components with high failure rate on site are classified,and then the fuzzy C-means clustering algorithm is used to obtain the regional clustering results of various component influencing factors.After comprehensive analysis of the regional partitioning results of various component influencing factors,the most consistent geographical region clustering results for overall reliability are obtained.By comparing and analyzing the on-site failure rates of this type of air conditioner in various provincial administrative divisions,the accuracy of the clustering results is verified.Secondly,the reliability model of the air conditioner is constructed.Based on the physical structure of this type of air conditioner,the detailed list of components,and the functional logic relationship between them,the reliability functional block diagrams of the entire machine and each subsystem are established.Further,the working state of air conditioning is analyzed and a working state sequence diagram is established.Based on this,a reliability model that can be applied to air conditioning evaluation and allocation is constructed by combining the reliability function block diagram.Thirdly,the regionalization calculation parameters under air conditioning and refrigeration mode are given.Based on the cooling load of building envelope in various regions of Chinese Mainland,the calculation parameters under the working mode of air conditioning and cooling in the reliability assessment model are regionalized,and the parameter values of various geographical regions under the working mode of air conditioning and heating are given by using the uniform design method.Finally,the application research of the overall machine reliability model was carried out.The built reliability model for the complete machine is applied to air conditioners operating in a cluster area consisting of seven provinces,namely Shanghai,Jiangxi,Anhui,Hubei,Hunan,Jiangsu,and Zhejiang,to evaluate their reliability,and the evaluation results are compared with the reliability point estimates derived from after-sales fault data.The results show that the maximum relative error of the two is0.47% and the maximum relative error of the cumulative failure probability is 4.27%when the air conditioner is continuously used for 5 to 10 years,which verifies the accuracy of the model.The reliability evaluation model constructed in this article can accurately predict the reliability of household variable frequency air conditioners,and can guide enterprises to formulate regional warranty and personalized marketing strategies.