Modeling And Optimal Scheduling Of Solar Energy Collection System For Absorption Solar Heat Pump

Solar energy as a clean new energy,the use of technology and application fields are also in rapid development and extensive gradually,absorption heat pump technology in the use of solar energy plays a more and more important role,how to improve the utilization rate of solar energy heat pump system to achieve maximum energy saving become urgent needs to solve an important problem.In this paper,aiming at the energy optimization utilization problem of solar heat pump system,the modeling method of solar heat collection system and absorption heat pump system is studied,and the optimal scheduling strategy of solar heat pump system operation is proposed by using the established model,and the maximum utilization of energy is finally realized.The main research contents of this paper include the following aspects:（1）Absorption solar heat pump system working principle analysis and experimental platform construction.By analyzing the working mechanism of absorption solar heat pump system,a solar heat collector system and a single effect absorption heat pump system with DMF-R134 A as working medium pair were built.In order to achieve better utilization of solar energy,installed on the system for a large number of sensing devices,such as temperature,pressure,flow rate to the running state of real-time detection system,at the same time in the system circulating pump,fan and other equipment installed a frequency converter,electronic expansion valve installed the stepper motor controller so that through the control device to realize the optimal operation of the whole system.（2）Based on the mechanism analysis of solar heat collection system,the hybrid modeling method and empirical modeling method for real-time prediction of solar heat collection system are proposed and compared.In the hybrid modeling method,firstly,the theoretical model of solar heat collection system is derived based on the basic principle of energy conservation and heat transfer mechanism of solar heat collection system,and the geometric parameters,empirical parameters and physical quantities that change little with the working state of the theoretical model are lumped into the unknown parameters of the model,and the structure of the hybrid model is proposed.Then,the TRNSYS simulation software was used to build the solar heat collection simulation system,and the steady-state data were obtained to identify the unknown parameters of the hybrid model.Finally,the PSO algorithm was used as the model parameter identification method to identify the unknown parameters of the model.In the empirical modeling method: Based on the analysis of the working principle of the solar heat collection system,the main factors affecting the heat collection of the solar heat collection system were determined,and the input and output structure of the system model was proposed.Based on the steady state experimental data collected by the solar heat collection system in real time,a neural network modeling method based on Radial Basis Function（RBF）was proposed.The comparison between the predicted value of the model and the experimental results shows that the two methods can predict the heat collection of solar energy collection system in a wide range of working conditions in real time and with high accuracy,and the errors are 2.02% and 3.80%,respectively.（3）BP neural network is used to establish the energy relationship model of solar heat collector and absorption heat pump system.Through the analysis of the working mechanism of absorption heat pump system,the main factors affecting the output of the heat pump system are described,the input and output structure of the system model is determined,and the energy relationship model between solar energy collection and absorption heat pump system is established by using the modeling method of BP neural network.The comparison between the predicted value and the actual value shows that the prediction accuracy of the model is high,and the error is only 3.25%.（4）Based on the model of solar heat collection system and absorption heat pump system,the optimal scheduling strategy of solar heat collection system is proposed.According to the relationship between the heat collection of solar heat collection system and the cooling demand of the heat pump system,the optimal control strategy of switching four working modes of solar heat collection system was proposed with the minimum power consumption of the heat circulation pump as the optimization objective and the equation constraint established by the model.By analyzing the changes of the temperature of the water tank,the solar energy guarantee rate and the power consumption of the thermal circulation pump,the feasibility of the optimal scheduling strategy is verified and the energy saving effect is good.