Research On Operating Reserve Requirement Estimation And Optimal Allocation Of Power System With High Penetrated Renewables

In a high proportion of new energy power system,the uncertainty of power supply side and demand side is enhanced,and the active power balance of power system faces severe challenges.The contradiction between the increasingly demand of operational reserve and the traditional reserve configuration criteria has become one of the most prominent problems in operation.As the proportion of new energy continues to grow at a high speed,it is not enough to rely on conventional unit to provide operational reserve for operation.It has become the key to meet the high proportion of new energy consumption by expanding reserve sources and exploiting flexible resources to participate in system regulation.In this thesis,based on the day-ahead scheduling period,the online dynamic assessment,classification fine management and optimal allocation of the system operation reserve capacity demand can be realized by considering the uncertainty of new energy and load prediction and the adjustment ability of multiple types of flexible resources.The main research contents and achievements include:(1)Analyze and reveal the seasonal,time period and predicted distribution characteristics of operational reserve capacity demand of high proportion of new energy power system,and simultaneously build a dynamic estimation method of operational reserve capacity requirtment based on clustering and kernel density estimation method.Reserve coverage probability(RCP),redundant reserve(RR)and Pearson product-moment correlation coefficient(PPCs)were used to analyze the adaptability of the evaluation results.In order to ensure the reliability of power supply and the requirement of new energy consumption,the new energy was brought into the next-day power balance scheme through the guaranteed power,and a strategy for making the capacity of conventional synchronous unit considering the requirement of dynamic operational reserve capacity was proposed,which provided reference for the dispatching center to make the generation scheduling for next-day.(2)Overall consideration is given to the operation characteristics of multiple types of resources of "source-network-load-storage",and the reserve level of each resource in operation scenarios is quantified based on the resource endowment of the highproportion new energy power system and related specifications and regulations.By expanding the reserve from conventional synchronous units to wind power/photovoltaic stations,energy storage devices,regional links and demand side,the interconnection and mutual benefit of various energy modes are promoted,and the problems such as high regulation pressure of conventional synchronous units and insufficient reserve capacity of the system are effectively alleviated.At the same time,an operational reserve capacity allocation criterion and optimization model based on the multi-subject characteristics of source-network-load-storage are proposed to realize the step-by-step fine configuration of operational reserve in the "network,the same resource and the unit",and to avoid the phenomenon of new energy abandoning and orderly power consumption to the greatest extent.(3)High proportion of new energy power system,the low level of inertia,the risk of transient frequency exceeding the limit under outage is large.According to the above problem,this thesis is based on the rate of change of frequency and frequency nadir,operating reserve capacity and equivalent inertia coupling analytical expression,build a frequency stability constrained reserve optimal dispatch model,and the corresponding iterative solution strategy is put forward.The model comprehensively considers the normal operation state of the power system(master problem)and the optimal allocation of reserve capacity under the contingency(subproblem).By giving full play to the advantages of deep fusion of source-networkload-storage,the frequency response capability of power grid under active power impact accidents can be improved.The simulation results show that the proposed model can significantly improve the frequency change rate/drop amplitude of the system,and improve the frequency quality of the high proportion of new energy power system.To summarize,the research results are helpful to reduce the reserve dependence on conventional synchronous unit,ensure the sustainable development of high proportion of new energy power system,and support the realization of dual carbon goals.