Strategy Study Of Various Peaking Methods Participating In Real-time Peak Load Regulation Of New Energy Power Generation Group

With the accelerating development trend of energy transformation led by clean energy,the intermittent,uncertainty and anti-peaking characteristics brought by the high proportion of new energy grid-connected power generation are becoming more and more significant,which aggravates the peaking pressure of power system.A single method of peak shaving is insufficient to meet the demand of peak shaving for new energy generation group.In recent years,many kinds of peak methods,such as pumped storage,concentrating solar power(CSP)and high load capacity have been rapidly developed.Different peak methods have unique regulation characteristics,such as large heat storage capacity,fast start-stop speed and high peak shaving flexibility,which lay the foundation for promoting the stability of peaking operation and the adequacy of peaking capacity.In addition,the joint optimization of peak shaving based on a variety of peak methods can make the peaking of the new energy grid-connected power system to achieve the effect of adapting to local conditions and complementary advantages.Therefore,it is an important way to achieve a higher proportion of new energy grid-connected dissipation and power system peak shaving stability by studying multiple peak methods involved in real-time peak shaving of new energy generation group.It has urgent theoretical research value and demonstration application significance.The main research contents are as follows:(1)Based on the analysis of the operation characteristics of new energy power generation group accessing to the local power grid in the Hexi area of Gansu,the output model of the wind power group and the photovoltaic power station group are established.The peaking operation mechanism of peaking methods such as pumped storage,CSP,hydropower generation and high energy load can be further elaborated in the peaking of power system.Based on in-depth study of the application scenes of various peak methods,the mathematical models of peak methods are established respectively.(2)Aiming at the problem of peaking operation caused by new energy power generation group in power grid,evaluation indexes considering wind-solar complementation and source-load coupling are proposed.Typical wind-solar power output scene models based on peak demand are established which have anti-peaking characteristic.These models use balance scenes and key scenes with its probability distribution which are based on improved Latin Hypercube Sampling(LHS)algorithm and scene reduction technology to illustrate the influence of wind-solar and peak demand.Afterwards,a peak shaving operation optimization model of high proportion new energy power generation group according to typical output models of new energy power is established.The various operating indexes of optimization in multi-scene peaking are calculated,and the ability of power grid peaking operation iscompared which takes into account wind-solar complementation and source-load coupling.Through a case of new energy power group in Hexi,Gansu Province,the feasibility and validity of the proposed operation strategy are verified.(3)Aiming at the problem of real-time peak shaving operation of new energy power generation group by multi-peaking methods,a real-time peaking optimization strategy based on multi-time scale and hierarchical control is proposed.Virtual power plant(VPP)uses advanced control strategy to aggregate a variety of distributed peaking methods,new energy power generation group and load agencies.Then VPP peaking control architecture is established,which breaks the geographical constraints of traditional new energy power generation,load and peak methods,and a platform for improving the comprehensive peak shaving capacity of new energy power generation group is created.Considering the dual characteristics of VPP's “source-load”,the peak payment function of source-load coordination is given,and a hierarchical scheduling mechanism for multi-VPP participating in real-time peak shaving of new energy power generation group is proposed.In order to reduce the prediction uncertainty error caused by random new energy output and load,a multi-time scale layered peaking optimization model that meets the opportunity constraints is established.The results of the study show that through the multi-VPP stratified and coordinated peak shaving mechanism and short time scale rolling peak optimization,a variety of peak methods are mobilized to participate in the enthusiasm,thereby achieving the peak balanced target within the system and increasing the peaking income.