Research On Wind-thermal Coordination Dispatching Strategy Based On UHVDC Transmission

China's wind power has developed rapidly.At present,many large-scale wind power bases have been planned and built in the “Three North” region,which is limited by the lack of local accommodating capacity and the phenomenon of wind abandonment is common.Utilizing Ultra High Voltage Direct Current(UHVDC)power transmission channels to realize wind and fire combined power transmission is an effective way to absorb large-scale wind power across regions.UHVDC transmission has the advantages of large transmission capacity and flexible adjustment.During the operation process,the transmission power is required to maintain a certain stability,and large power fluctuations affect its safe and stable operation.Therefore,the UHVDC transmission path requires that wind and fire joint output be stable.The traditional DC operation is generally operated in a constant power mode,and the load characteristics of the receiving end network are not fully considered.The DC outbound wind power supply still has a large potential for peak adjustment.How to tap the peaking potential of the wind power supply through DC scheduling has great research significance.This paper first analyzes the basic composition,characteristics and operation control methods of UHVDC transmission system;analyzes the fluctuation characteristics of wind farm output and defines the cumulative curve of wind power climbing;proposes a method for determining the matching thermal power capacity based on cumulative curve of wind power output.Then,based on the joint dispatching of UHVDC outbound wind and geothermal power,a model for maximizing wind power consumption and a peak load dispatching model based on the receiving power grid were established.On this basis,UHVs were established to coordinate wind power consumption and receiver peak shaving.DC combined with wind and fire combined power dispatching model.The CPLEX software was used to simulate the traditional fixed power mode and the coordination of wind power consumption and the receiver peak load adjustment scheduling model.The results show that the supporting thermal power generation based on cumulative curve of wind power output climbing capacity can meet the requirements of fluctuating wind power fluctuations and make reasonable use of the sending end power grid.The capacity of peak regulation,the establishment of a scheduling model to play UHVDC DC wind power supply peaking potential,increase the receiver peak power margin.Finally,the fixed auxiliary thermal power capacity cannot fully consider the peak-receiving capacity of the sending end of the power grid,and the analysis scenario is expanded.The sending end does not limit the matching thermal power capacity.The receiving end no longer considers only the load characteristics,and considers the sending and receiving end power grid networks.safe question.A receiver-based power grid based on a fully constrained network can be used to safely accept the DC power limit model,and the model compiles and solves to obtain the upper and lower limits of DC transmission power safety;and a DC dispatching model based on peak-receiving of the receiving power grid and feed-side wind power consumption is established to send The end network security and DC power security constraints are constraint solutions.The example simulation shows that the model is effective for improving the peaking margin at the receiving end and the wind power consumption level at the sending end.The purpose of this paper is to refine the UHVDC dispatch curve,improve the peak shaving margin of the receiving grid,and improve the wind power consumption level of the sending grid.This can provide reference for the dispatching plan of the UHVDC transmission and receiver grid dispatching departments.