Research On Grid-connecting Wind Farm Power Compensation And Energy Storage Capacity Optimization With VESS

Along with importance of environment being more and more realized, renewable energy gets great development, and now wind power is the most mature and widely used renewable energy technologies. Because of the randomness and volatility of the wind power, wind-farm output easily impacts on the grid when it parallels, and as the large-scale development of power farm, the impact consequences will become worse, which has become the bottleneck problem about how to be more widely used. Energy storage can effectively improve the output power fluctuations of the wind farm, but the devices cost of energy storage is high, which limits the application of energy storage technology, so research the technology and reduce the of energy storage capacity is very important. for the more large-scale application and development of wind power.This paper firstly according to the volatility and uncontrollability that wind turbine output power has, and analyzes the impact of large-scale wind power on power system’s voltage, frequency, stability and scheduling.Secondly, depending on the characteristic of VESS (Vanadium Redox Flow Battery Energy Storage System) and the principle of VRB (Vanadium Redox Flow Battery), the paper builds the equivalent circuit model and simulation model of VRB, and validates the normal working range of the state of charge. And the energy storage device installation site is optimized, the simulation analysis can prove that the VESS is configured in exports bus of wind farm can improve the fluctuations of wind power.Finally, the paper analyzes the factors affecting the energy storage capacity, and adopts three different control methods:takes the annual average power as the benchmark power of wind farm; uses the forecasting technology of wind power to forecast the average power of next period as the benchmark of wind power; combines the SOC feedback and the forecasting technology of wind power, and optimizes the energy storage capacity. The simulated analysis uses the data actual of wind farm, and observes compensation effects of wind power under different methods, combined with the determined standards of the compensation effect that the paper raises, and the results show that the method based on the SOC feedback and the forecasting technology of wind power can get better active power compensation effect.