Design And Evaluation Of Photovoltaic Power Forecast System

With the gradual depletion of traditional fossil energy,the problem of global energy supply becomes more and more serious.As a green and sustainable new energy,photovoltaic power generation can not only alleviate energy crisis,but also alleviate various environmental problems caused by fossil energy.As more and more photovoltaic power stations are built and put into operation,photovoltaic power generation is bound to occupy a larger and larger share of the energy generation in the future.It should be noted that photovoltaic power generation has obvious fluctuation and randomness.It’s output power is affected by many meteorological and environmental factors,as well as its own structural characteristics.The high and insufficient output of photovoltaic power will affect the safe and reliable operation of the power,grid Photovoltaic power generation brings great challenges to the real-time power generation,transmission and consumption of the power system,which leads to the inefficient utilization of photovoltaic power generation in the distribution network,and seriously restricts the safe and reliable absorption of photovoltaic power generation.This also limits the integration of large-scale PV systems into the grid.The scheduling of power grid system also involves many time periods,which needs the data support of different time scales of PV power forecasting.Therefore,it is necessary to study the forecasting model of PV power generation,in order to promote the PV power dissipation and ensure the safe and stable operation of power grid under bloom power permeability.It is very important for the security and dispatch of power network to predict PV power accurately and to adopt corresponding distribution power optimization control strategy.Based on the summary of the research progress in the field of photovoltaic power generation in recent years,the photovoltaics is analyzed and studied in this paper.The main contents of the thesis are as follows:(1)The basic structure,principle and mathematical model of solar cells are introduced,and the characteristics of photovoltaic cells are analyzed the unreliability of power generation calculation by mathematical model in practical engineering application is pointed out.Then,the main factors that affect the output power of PV are analyzed.The effects of wind speed,relative humidity,radiation intensity,temperature,haze and weather conditions on the output of PV system are analyzed and checked.This paper summarizes the problems existing in the photovoltaic power generation prediction.(2)The forecasting method of photovoltaic power generation is studied.Firstly,the photovoltaic power forecasting method is described,and the WRF mode operation framework and basic principle,as well as the artificial neural network related process algorithm are introduced.Finally,BP neural network algorithm is selected to predict the photovoltaic power generation.Considering the photovoltaic power generation system is a nonlinear system,and its output power is fluctuant and indirect because of the coupling effect of its component characteristics and various weather factors.When using the neural network algorithm,we do not need to consider the coupling relationship between variables and do not need to fit,only need to train the historical data of the input variables and the output variables,so that the neural network can continuously learn and self-optimize,then the relationship model between input and output can be obtained.(3)A photovoltaic power forecasting system is developed.The logical structure of PV power forecasting system,the suitable software development platform and database are analyzed for the system development.It mainly includes user management module,real-time data display module,statistical report module,system management module and other functional modules.According to the test after deployment,the system can meet the design requirements and run stably.(4)The corresponding index evaluation system of PV forecasting and evaluation system is established,and some suggestions are put forward for the construction of PV power station.