Research On The Comprehensive Utilization Technology Of Photovoltaic And Heat For Intelligent Household

The development of human society is inseparable from the use of energy.In the process of the use of human energy,the tension of energy relations and environmental pollution caused by fossil energy such as coal,oil and natural gas have become increasingly prominent,which has gradually affected or even restricted economic development.Therefore,with a series of renewable clean energy gradually entering the world stage,the strategic direction of future energy development will eventually be the development and utilization of clean energy such as hydropower,wind energy and solar energy.New energy has become the theme of world energy development.As a clean and renewable energy,solar energy has attracted more and more attention.Since the 20th century,the development of new energy such as photovoltaic has made great progress.However,when people use solar energy,they pay less attention to the decentralized characteristics of solar energy.When a large number of centralized photovoltaic power stations are connected to the power grid,the development of distributed photovoltaic is also more important.For distributed photovoltaic users,this dissertation proposes a construction scheme that effectively combines solar energy with photovoltaic power generation.Firstly,a special-shaped cylindrical flat lens is designed on the concentrating power generation system to realize low power focusing photovoltaic power generation.Experiments show that when the focusing multiple is 15.2 times,the relative efficiency can reach 95.4%,and 80% of the monocrystalline silicon cells can be saved.After power generation,80% of the remaining photovoltaic energy is used to heat water,which can improve the water temperature to 70 ℃.Secondly,in the control of biaxial orientation technology,due to the low focusing multiple required by the system design,the two position control method with lower cost is adopted,and the self-made pyramid direction sensor is used to solve the problems of high-precision orientation and wide range search;Using DC motor instead of servo motor and its controller is more suitable for the slow motion requirements of tracking sunlight,and the cost is lower.Thirdly,in order to make better use of the heat energy,the surface soil is used as the heat storage medium to establish a heat island,which is protected with thermal insulation materials outside the heat island to store the heat energy.The heat storage effect and temperature variation range of the heat island are preliminarily estimated,the heat conduction equation and the temperature distribution diagram of the heat field in the heating process are derived,and a new method of indoor hot air heating is proposed.At the same time,the mechanical strength of the insulation material around the heat storage medium is analyzed,and the specific measures to optimize the stress are put forward.Then,aiming at the islanding effect in solar grid connected power generation,a new solution,the current loop correlation function sampling method,is proposed to avoid the disadvantages of easy interference and low reliability in the passive sampling method,as well as the pollution of the active sampling method to the power grid quality,so as to obtain a reliable and clean solution to the islanding effect.Finally,in order to obtain a grid connection system more suitable for distributed photovoltaic users,a three-phase active rotating inverter is developed by using the rotor of an ordinary DC motor plus permanent magnet poles and pilot switches.The grid connection operation is the same as that of an ordinary generator.When the voltage and frequency are close,when the phase synchronization is connected to the power grid,it will be pulled into synchronization by the power grid.Even if the grid connection fails,there will be no disastrous consequences.The integrated thermoelectric solution system provided in this paper uses low power focusing to reduce costs and improve heat recovery efficiency.The consumption of silicon cells can be reduced by more than 80%,and the power generation efficiency is 62% higher than that of fixed silicon solar energy;The water temperature can be increased to 70 ℃;The loop current sampling method is used to solve the islanding effect on the user side,and the three-phase active rotary inverter is used to solve the problems of expensive inverter and grid connected electromagnetic pollution,which improves the reliability of the system.