Study On The Optimal Allocation Strategy Of Wind-solar Hybrid Generating System Based On Power Forecast

With the increasing installed capacity of wind power and photovoltaic power generation, the problem of large-scale renewable electricity generation was becoming increasingly significant. Such as wind energy and solar power generation of weather dependent characteristics, making the output to present the obvious randomness and the power quality would be low, dispatching control difficultly by the power grid. It needs to be studied that how to allocate and regulate the renewable energy power generation that intermittent more obviously by rational strategy to meet the load demand. As well as the research of the optimization strategy that can stabilize the output power fluctuation of the wind and photovoltaic hybrid power is also important.In order to improve the power quality effectively, improving the power supply reliability of renewable energy power generation system, increasing the intermittent type electric energy utilization rate, reducing pressure on the environment, this paper analysis and research the energy optimization strategy of the hybrid power generation technology from the following three aspects.Firstly, this paper establishes and simulates the prediction model of wind-solar hybrid generation power. After analyzing the feasibility of hybrid power generation, it models the wind and photovoltaic power generation system. Then, it establishes the wavelet packet neural network(WPNN) prediction model and predict the future 5days of power. Through the field data simulation, the results show that, compared with the traditional model, the prediction accuracy of WPNN model is significantly improved and meets the requirements of the power grid, which is less than 20%.Secondly, this paper studied the power allocation strategy of hybrid power generation based on tracking load. Studying on modulating peak characteristics and complementary advantages of wind power and photovoltaic power, this paper proposed the allocation strategy according to the configuration object and relatedconstraints. Allocating the system power based on principle that improving the power utilization ratio in the initial configuration strategy, it achieved the purpose of tracking load curve roughly. Then, this paper compensated and optimized the part which appear the power outage or energy redundancy in initial strategy by energy storage, to further meet the load and improve energy utilization. Finally, the combination of power forecast data and the actual load data simulation prove that step-by-step configuration strategy has tracking ability to the load, reducing the outage rate and energy redundancy, improving power supply reliability.At last, for the phenomenon that complementary system output is difficult to control because it has large fluctuation and requires a large hot-spare capacity, this paper put forward an optimization smoothing strategy to the power in order to stabilize power fluctuations. Firstly, it selected smoothing index and analyzes real-time restraint object, and then uses moving average algorithm to stabilize the combined output power. As the output curve of the target, it configurate the wind and solar power output reasonably with energy storage. Eventually it make the joint power output curve fit the target. The simulation results show that the optimization strategy can realize the output power fluctuation smoothing, reducing volatility and meet the control requirements of the power grid.