Wind Uncertainty Countermeasure Strategy Based On Power Forecasting

The wind power industry is developing rapidly.By the end of 2019,the capacity penetration rate of wind power had exceeded 10%.However,the randomness,anti-peak regulation and low schedulability of wind power output often lead to the phenomenon of wind power curtailment,and even lead to large-scale off grid accidents of wind power units.Grid connected consumption and safe operation of the system have become one of the bottlenecks in the scale development of wind power in China.In this study,the uncertainty of wind power output and the impact of uncertainty on the power grid,large-scale energy storage scheduling strategies and scheduling strategies for flexible load participation in demand response are studied in depth.The load fluctuation characteristics of wind farm and demand side are studied in depth based on the historical data.The influence of uncertain output of wind power on peak load regulation and dispatching of power system is analyzed,and the important role of wind power forecast in countermeasure uncertain scheduling of wind power is described,which lays a theoretical foundation for large-scale grid connected wind power consumption.Aiming at the problem that the prediction error is inevitable in the power prediction process and is positively related to the prediction time scale,a peak shaving control strategy based on dual time scale payload prediction is proposed.And the energy storage power stations are used as auxiliary peak shaving resources.The two uncertainties of wind power and load will be taken as a whole.The number of variables is reduced during data processing and the errors in prediction are reduced too.In the day ahead planning stage,optimization of energy storage charging and discharging sequence with minimum output of conventional peak load regulating units as objective based on the day-to-day power prediction.And the power range of tie line after peak load regulation is established to provide power reference range for rolling regulation in the day.In the rolling adjustment optimization phase,VMD-SaE-ELM is used for ultra-short-term prediction of net load.And based on the predicted value of the ultra-short-term net load and the power interval established a few days ago,the reference power for peak regulation is adjusted dynamically to modify the energy storage charge and discharge power.The analysis of example shows that the proposed control strategy can effectively reduce the peak valley difference and power fluctuation of the net load.The load flexibility is used to deal with the uncertainty of wind power.The cluster electric vehicles are taken as demand response resources.A demand response scheduling strategy for cluster electric vehicles based on load aggregator model is proposed.This strategy implements unified management of electric vehicles connected to the grid through the load cluster dispatch center.The proposed method can adjust a reasonable response reference power outside the cluster according to the net load prediction information and the operation status of the energy storage power plant.A hysteresis model of electric vehicle charging is established within the cluster.The charging sequence of electric vehicles is adjusted in an orderly manner based on quantified indicators such as the frequency of electric vehicle charging switching,the degree of deviation of the charging trajectory,and the state of charge.The real-time regulation of the cluster charging power can be achieved.The example analysis shows that the proposed strategy can make full use of the forecast information to further reduce the power fluctuation of the net load.The analysis of example shows that the demand response scheduling strategy proposed in this paper can not only track the power fluctuation of wind power,but also participate in peak load regulation to further reduce the power fluctuation of net load and reduce the peak load regulation pressure brought by the uncertainty of wind power to conventional units.Large-scale energy storage and electric vehicles to participate in peak load regulation are be made full use on the basis of power forecast in this paper.The peak load caused by the uncertainty of wind power to conventional units is reduced,and the wind power consumption capacity of the power system is improved.