| At present,my country is facing the new situation of "carbon peaking and carbon neutrality".The clean energy industry represented by wind power is developing rapidly.The high proportion of wind power consumption is a challenge for the flexible operation of the system.How to deal with the large-capacity grid-connected wind power may cause a sharp increase in peak shaving costs,and the traditional hour-level dispatch may not be able to accurately track load changes due to wind power fluctuations have become urgent research issues,in this regard,based on the energy storage configuration,this paper constructs an optimal scheduling model of wind-thermal-storage for the self-adaptive segmentation of the net load curve to improve system flexibility under different time granularities.The main research contents are as follows:(1)The mathematical model of wind power and energy storage system is established.According to the operating characteristics of wind power and the relationship between wind speed and wind power,the uncertainty model of wind power is established;in view of the influence of wind power on the system’s peak-shaving capability,the charging and discharging power model of the energy storage system is established by using the role of peak shaving and valley filling of the energy storage system.(2)An adaptive segmentation model of net load curve considering multiple time granularities is established.To flexibly deal with the fluctuation of wind power and load,the concept of time granularity is introduced,and the impact of time granularity division on system operation is analyzed;on this basis,a reasonable wind curtailment model is established under different time granularity to minimize the net load variance,optimize the wind curtailment and energy storage charging and discharging power in each period;for the problem that the system dispatching time increases exponentially and the net load deviation increases after the time granularity division,this paper proposes an adaptive classification of the net load curve that does not change the total dispatching period.The section model makes the optimized net load curve relatively smooth,and at the same time increases the system operating speed.(3)A double-layer optimization model of energy storage configuration and system economic operation is established.On the basis of the double-layer optimization model theory,the upper model considers the subdivision of time granularity,the upper model establishes a storage capacity allocation model based on time-granularity partition to determine the storage capacity and charge-discharge power limit.The lower model establishes an optimal scheduling model considering peak shaving cost and carbon trading on the basis of reasonable wind curtailment model and adaptive segmentation model solution of net load curve,and jointly improves the PSO algorithm and NSGA-Ⅱ algorithm to solve the upper and lower models.(4)Taking a certain area in Northwest China as an example,the model built in this paper is simulated and solved in multiple scenarios.According to the simulation results,it can be seen that considering the appropriate amount of wind curtailment and the "peak-cutting" effect of the energy storage system at different time granularities,it can Effectively respond to changes in wind power and load,and reduce the peak-to-valley difference of the net load curve;on this basis,the self-adaptive segmental optimization of the net load curve can effectively reduce the deviation of the net load curve;it shows that the proposed method effectively improves the flexibility and economy of the system. |
