Study On High Efficiency Defrosting Control Of Air Source Heat Pump In Tibetan Area Of Western Sichuan

The Tibetan area of western Sichuan is located in the Sichuan-Tibet Plateau and lacks fossil energy,but its hydropower resources are abundant.Air source heat pump,as one of the efficient renewable energy application technologies,has great advantages in environmental protection and energy saving,and has broad application prospects in the region.However,it needs to operate under the typical conditions of "low temperature and high humidity" in Tibetan area of western Sichuan.Frequent frosting is the biggest problem,and the unit's defrosting operation will also cause the operating burden and indoor thermal environment instability.In view of this problem,this paper starts from the perspective of control and considers the instability of the climatic conditions in Sichuan and Tibet to be difficult to predict.We have chosen to use fuzzy control methods to study the control of defrosting Strategy and formulate an effective frost control strategy for Tibetan area of western Sichuan.First,the research team conducted field surveys and tests on Hongyuan,a typical county seat in the Tibet Autonomous Region,and obtained indoor and outdoor natural weather conditions during the local heating season.The reasons for the low frequency of use air source heat pumps in the region were analyzed.The natural climate features of “low temperature”,“high humidity”,and “high altitude” are the main environmental factors that hinder the use of air source heat pumps in the region.The research results provide the basis for the fuzzy controller input selection and the establishment of fuzzy rules.Secondly,according to the requirement of air source heat pump defrosting control,based on the theory of fuzzy control and the study of frost patterns,the fuzzy control rule base and the membership functions of each input variable are established using MATLAB,and a simplified two-dimensional blur is designed.The controller determines the degree of frost formation and performs simulation modeling evaluation through Simulink,the controller evaluation result is good.Finally,with the goal of “high-efficiency frost control” and reducing false defrosts,a defrosting control strategy for Tibetan area of western Sichuan was formulated.Based on the conventional defrosting control “temperature-time” method,this paper incorporated a fuzzy frost-degree determining controller,evaluated the frost-blurring degree as the starting point of defrosting,and constructed a self-adjusting and regional adjustment strategies make the frost control strategy sound and reliable.It is hoped that the defrosting rate can be reduced,which will serve as a guide for efficient frost-control related technologies.