Research On Optimal Sizing Of Energy Storage And Operation Strategy Of Micro-grid With Wind Power

Among the renewable energy power generation technologies,wind power generation is one of the fastest developing technologies.However,wind power is affected by climate and shows strong volatility and uncertainty,making wind power generation to be a random and uncontrollable generation.Energy storage technology provides reliable support for enhancing the controllability of wind power generation due to its flexible charging and discharging characteristics.The size of the energy storage system and its compensation effect for wind power generation show a great correlation,and the size will also affect the installation and maintenance costs directly.Therefore,determining the optimal size of the energy storage system is essential for the optimal operation of the micro-grid and the use of wind energy.At the same time,the micro-grid has excellent local power supply ability through the integration of various energy sources,which can provide solutions to the electricity demand in remote areas or areas with insufficient electrification,and plays a major role in promoting the full utilization of renewable energy.Therefore,the determination of micro-grid operation strategies considering different generation ability of different energy sources are also one of the current research focus.This paper takes the micro-grid containing wind power as the main research object,and focus on the research about the optimal sizing of energy storage and the operation strategy of the micro-grid.The main tasks are as follows:(1)Aiming at the volatility of wind power generation,an energy storage size determination model considering the operating cost of the micro-grid was established,and the solution was obtained by an improved fruit fly algorithm.The algorithm improves the diversity of the population through the modification of the group location update strategy.Then the self-adaptation of the individual random movement step was introduced.Finally,the total operating cost of the micro-grid that integrates the fuel cost,energy storage cost and power purchase cost was chosen to be the objective of energy storage sizing problem.According to the comparison with other algorithms in two different operating modes of the micro-grid,shows that the improved algorithm can effectively solve the energy storage sizing problem considering the operating cost of the micro-grid.(2)Aiming at the prediction error of wind power generation and random outage events,an energy storage size determination model considering the reliability of micro-grid was established.Firstly,the prediction error was simulated by some scenarios generated by scenario generation and reduction technology;Secondly,chance constraints were built for random outage events to ensure the normal operation of important loads when outages occur.The method was applied to the micro-grid,and the results show that after considering the uncertainty of the forecast error and random outage events,the energy storage size configured is beneficial for the system reliability,and the load loss rate and the expected value of power shortage can be reduced.(3)Aiming at the operation problem of micro-grid containing wind power generation,the information gap decision theory was used to consider the uncertainty of wind power output.When the uncertainty distribution is unknown,the appropriate operation plan can also be obtained.Firstly,the energy storage loss cost was considered to build the micro-grid operation optimization model.Then,based on this model,the uncertainty of wind power was further considered,and the disadvantages and benefits of the error between the actual value and the predicted value of wind power are comprehensively analyzed,so as to provide a reasonable operation plan for micro-grid decision-makers.