| With the rapid economic growth,the exhaustion of fossil energy and environmental pollution problems have followed one after another.The development of renewable energy and environmental protection have become universally recognized survival criteria.Among them,the solar heat pump hot water system using clean and pollution-free solar energy combined with energy-efficient heat pump technology has gradually become a hot spot in energy research.The development of solar heat pump hot water technology in China is still in its preliminary stage.How to further realize energy saving and consumption reduction and ensure stable hot water supply will be the focus of the next theoretical research.To this end,this article has done the following work for the parameter matching and optimal scheduling of solar heat pump systems:(1)Research on the optimal matching of system design parameters.Establish a system mechanism model,based on historical meteorological data,combined with actual industrial conditions,take the system energy efficiency ratio and dynamic monthly cost as the objective functions,and study the influence of the design solar guarantee rate and the design water supply temperature on the system under a single target condition.At the same time,in order to balance the contradiction between system performance and economic issues,a multi-objective function optimization solution was proposed,and the design parameter values based on the weather conditions of different months were obtained.(2)Research on the optimal matching of system operating parameters.The selection of the heat pump unit is determined according to the lower limit of heat pump heating capacity under extreme conditions;and its rated power is 9.6k W;the dynamic annual value method is used to obtain the best match when the solar heat collection area is 498m~2.The solar energy revenue is the objective function,When the ratio of the volume of the water tank to the effective heat collection area of the collector is0.08,that means when the volume of the water tank is 40m~3,the solar energy benefit is the highest;by using the Hay anisotropic model,find that the collected radiation is the largest when the inclination angle of the collector is 30°.The values of operating parameters can be verified by actual working conditions.(3)Establish a prediction model for the whole process of the system.By analyzing the changes in solar irradiance under the conditions of typical irradiance days in the four seasons,a solar radiation forecast model based on normal probability distribution is established,and temperature compensation values are introduced to predict the radiation at each time period to ensure that the error is less than8%;analyze the impact of ambient temperature and water tank temperature on the operation of the heat pump,and use a large amount of actual operating data to fit the heat pump energy efficiency ratio COP and power P to estimate the heat pump heating capacity;combine the user’s historical water use data The forecast of water consumption in a single day shows that the average error for the whole day is 6.39%.(4)Analyze the shortcomings of traditional control strategies and propose new optimal scheduling schemes.The lowest operating cost of the heat pump is taken as the optimization goal,at the same time,consider constraints such as heating demand,water storage temperature,water storage,and water replenishment,the system scheduling problem is studied.The results of the study show that in regular sunny days,the optimized scheduling scheme reduces the operating costs of the heat pump by 27.4%,and the average COP of heat pump units increases by about 10.7%;under normal cloudy days and extreme cold weather conditions,this optimized scheduling scheme can ensure the stable and efficient operation of heat pump units and meet user water demand. |
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