Research On Power Generation Planning Considering Inter-Regional Allocation Optimization Of Flexibility Resources

In order to cope with the challenges posed to the safe and stable operation of the power system by the large-scale grid-connection of new energy under the "double carbon" target,it is necessary to construct a variety of flexibility resources.Flexibility supply and demand has become an urgent issue to be studied in the planning of high proportion renewable energy power system.Flexibility resources exist widely in all aspects of the power generation,grid,load and storage,with the power supply side currently dominating.With the gradual completion of the energy internet,the grid side will participate more frequently in the balance of power supply and demand.With the gradual completion of the global energy Internet strategy,the grid side will participate more frequently in the balance of power supply and demand.In contrast to conventional regulating sources,the interconnected grid does not produce and consume electricity itself.However,by exploiting the complementary timing characteristics of net load between different regions and interconnecting each other in the spatial dimension,the interconnected grid can also achieve similar effects to other flexibility resources.Therefore,under the objective of new power system construction,it is not only necessary to reasonably allocate resources based on the system’s flexibility supply and demand,but also to give full play to the flexible dispatching capacity of transmission channels.In order to meet the requirements of safe grid operation and to analyze the impact of grid interconnection on resource allocation,this paper constructs a power planning model that considers the optimal allocation of flexible resources across regions.It is committed to using cross-regional transmission channels to allocate flexible resources,thereby promoting the consumption of new energy at a smaller economic cost and providing support for the coordinated development of regional power grids.Firstly,this paper explains the theories and methods related to power system flexibility.cross-regional allocation of power resources and power generation planning.It explains the mechanism of the flexibility supply-demand balance,and assessed the regulating capacity and regulating costs of flexibility resources from both technical and economic perspective to determine the supply capacity of flexibility.It also introduces the factors influencing cross-regional allocation,the benefits of grid interconnection and commonly used power generation planning methods.Secondly,based on the above theories,this paper further analyses the supply-demand balance of flexibility.The net load curve is obtained from the random output sequential simulation of new energy,and the maximum variation and maximum continuous variation of the net load curve is used to characterize the system flexibility requirements.A linear equation for the amount of net load variation against the total installed share of wind and solar power is obtained by fitting to quantify the need for flexibility.As a result,this paper constructs a power generation planning model that considers flexibility supply and demand,satisfying the constraint that the flexibility adjustment capacity in each directions is not less than the corresponding flexibility demand.To further consider the impact of cross-regional transmission,this paper proposes the concept of load demand simultaneity between regions,and a series of quantitative indicators of load demand simultaneity are developed on the basis of the conventional load characteristic index system.Then,the paper constructs a power generation planning model that considers the optimal allocation of flexible resources across regions,incorporating flexibility supply and demand balance,cross-regional power transmission,non-simultaneous load demand between regions and the associated costs,and integrating all aspects of power generation,grid,load and storage to optimize the cross-regional allocation of resources.Finally,the model is applied to study the case of power generation planning of the Northwest to Central China Power Grid from 2021 to 2035,and the scenarios are compared and analyzed to verify the need for a flexibility supply-demand balance and the effectiveness of carrying out inter-regional resource sharing.The power generation planning results show that flexibility supply and demand balance is the key to the safe and stable operation of new power systems.Moreover,interconnections that take advantage of differences in load characteristics between regions can facilitate the allocation of power resources on a larger scale and achieve synergistic optimization of interconnected power systems.