Study On Solar Heat Pump Heating System Based On Fuzzy Smith Control

In recent years,the gradual depletion of fossil energy has made the use of new energy more and more important.Among the various new energy types currently being developed,solar energy has received great attention because of its abundant reserves and its convenient access.Among various solar energy utilization methods,solar heat pump is a low-cost,widely used,economical and environmentally friendly utilization method.The loose coal combustion and heating in the vast northern regions of China,especially in the cold regions of the north,is not only costly,but also produces a large amount of dust and other polluted atmosphere.Therefore,solar heat pump heating is designed for the cold regions in the north,and the heat pump system is optimized under the condition of ensuring sufficient heat supply for the load to achieve lower economic costs.This paper designs a complete solar heat pump heating system for a two-storey duplex building in Baotou.The system adopts an aluminum tube solar collector specially designed for the cold regions in the north to construct a solar heat pump system as an evaporator.Based on the climate and environmental data of Baotou area and the structure and material characteristics of the building itself,the thermal load of the building was calculated.And for the load selection system components include compressors,plate heat exchangers,electronic expansion valves,solenoid valves and other specific models.According to the thermodynamics and heat transfer analysis of the heat absorption condition of the aluminum tube solar collector,the optimal collector area is selected for the absorption of solar energy and air energy under different working conditions of the collector to achieve the collector part manufacturing.The minimum cost of combined costs and operating costs.The effects of wind speed,ambient temperature and solar radiation intensity on heat collection and heat collection efficiency of aluminum tube collectors are analyzed to provide reference for the collector installation environment.Mathematical model is established for the system to analyze the influence of various components such as compressor and expansion valve on the operation of the system,and provide reference for the operation mode of the system.The solar heat pump system simulation platform was built by Matlab/Simulink to simulate and analyze the heat collection of the solar collector and the overall performance of the solar heat pump system.Design a set of frequency conversion speed control circuit based on SVPWM modulation for the drive and speed control of the compressor,and complete the design of the main circuit ofthe variable frequency speed control circuit and the design of the detection circuit and IGBT drive circuit.The control of the superheat of the collector is studied,and the electronic expansion valve drive circuit is designed to design the initial opening degree of the electronic expansion valve according to the climate condition at the beginning of the heating season.According to the characteristics of the nonlinearity and large inertia of the collector superheat system,the fuzzy Simth control algorithm is designed to control the opening of the electronic expansion valve based on the traditional PID,improve the system response speed,reduce the system overshoot,and achieve better results.Heat control effect.