Research On The Capacity Of Flexible Loads To Consume Offshore Wind Power And Its Multi-Timescale Hierarchical Regulation Strategy

China’s offshore wind farms have continued to grow rapidly in terms of grid-connected capacity under the goal of"peak carbon and carbon neutrality".However,the issue of large-scale wind power grid-connected absorption is increasingly prominent due to the inverse spatial and temporal distribution of wind power output and load,the impact of charging power on submarine cable transmission,and the uncertainty of wind power forecasts at different time scales.Therefore,this paper mainly focuses on how to consider the matching relationship between the uncertainty of wind power output and the adjustable potential of flexible loads,the coordinated scheduling method of flexible loads under multiple time scales,and the calculation of the maximum injected power of wind power and wind power consumption capacity considering charging power.The main contents:(1)In view of the uncertainty of wind power prediction accuracy under different time scales,a control model for the participation of flexible loads in wind power consumption under multiple time scales that simultaneously considers both power optimization with day-ahead time-sharing tariff response and power optimization with intra-day incentive compensation control is proposed.And a hierarchical coordination control model combining direct-indirect control of different types of flexible loads in different regions is proposed.In addition,the types of daily fluctuations of wind power are accurately classified as small interval fluctuations,convex fluctuations,concave fluctuations,rising enhanced fluctuations and falling weakened fluctuations.Thus,the feasibility of using flexible load to adjust the potential of multi-level consumption of blocked wind power is analyzed.(2)In view of the serious interference caused by the charging power of submarine cables to the maximum injected power of wind power,the calculation method of the maximum injected power of wind power in offshore wind farms under different reactive power compensation methods is proposed.In view of the situation that the peaking shaving of system restricts the level of wind power consumption and there is a certain relationship between the system’s peaking shaving and wind power fluctuation.The analysis method of the matching relationship between wind power fluctuation and the system’s peaking shaving under daily scale is proposed.Besides,the calculation method of wind power consumption capacity is proposed too.The system peak regulation type is divided into incentive fluctuation type,stable fluctuation type and wind abandonment fluctuation type when the wind power is connected to the grid.According to the example analysis of a terminal power grid,the typical daily load level is high in summer,and the system has sufficient peak regulation margin to accept wind power installed capacity with a penetration rate of about 12.4%to the grid,while the typical daily load level in winter is low,only the wind power installed capacity with penetration rate of about 2.6%can be accepted to the grid.(3)Finally,a day-ahead control model including air conditioning thermal control load,electric vehicle charging load and a daily control model with high load energy load are established to participate in the consumption of offshore wind power in different levels.This paper establishes an optimized objective of customer satisfaction considering the cost of EV charging,the deviation of the battery charge state and the cost of other loads that can respond to the time-of-day tariff.What’s more,an optimized objective of the minimum blockage rate of wind power under day-ahead and day-in dispatching is also established.The model is solved using a non-dominated ranking genetic algorithm with an elite strategy to enhance local search capability.A simulation study using actual operational data of a receiving grid is conducted.By comparing the different types of flexible load power consumption within this receiving grid before and after the planning,the abandoned wind power rate is reduced from the original 38.61%to 30.58%;the blocked wind power is facilitated to be dissipated by 1.5015×10~3MW accounting for 22.22%of the original blocked wind power.This paper verifies the effectiveness of the proposed strategy.