| The main development trend of modern power systems is to gradually shift from the original fossil energy power generation to new energy power generation.And,the most fundamental difference between new energy power generation and conventional power generation is the randomness,intermittentness and semi-controllability of its output power.In the process of new energy development,as the penetration rate of new energy in the power grid gradually increases,it is a huge challenge for the power grid to absorb new energy.It is imperative to improve the peaking capacity of the power grid and promote the consumption of new energy by the power grid.China’s water resources are abundant,and the scale of hydropower is large.Considering the use of hydropower regulation capacity,a wind-water joint operation system is established to stabilize wind power output fluctuations and promote wind power consumption,so that the advantages of these two clean energy sources can be complemented.In order to solve the problem of insufficient peaking capacity of the system caused by the increase of new energy permeability,considering the potential of peaking hydropower,the paper studies the operating characteristics and mathematical model of cascade hydropower,and gives the linear and nonlinear constraints of cascade hydropower operation.The equivalent model of cascade hydropower virtual pumping station is constructed from the aspects of water conservancy and electric power.Based on the cascade hydropower centralized control mode,the cascade hydropower virtual pumping station dispatching method is proposed.It can explore the peaking potential of cascade hydropower and provide a theoretical basis for the joint operation of wind and water.The paper analyzes the complementary characteristics of wind power and hydropower.Considering the cascade hydropower constraints and the randomness of wind power output power,a wind-water joint operation scheduling strategy with minimum output power fluctuation as the objective function is proposed,and the Gansu field data is used for simulation analysis.The results show that this method can significantly reduce wind abandonment when the transmission line sending capacity is matched.However,in the case of further development of wind power,the wind-water joint operation scheduling strategy with the minimum output power fluctuation as the objective function can not effectively reduce the wind abandonment.This paper proposes a wind-water joint operation scheduling strategy based on virtual pumping power station.The aim is to minimize the abandonment of wind by exploiting the peaking potential of cascade hydropower.The simulation results show that the proposed method can effectively promote wind power consumption when the transmission line sending capacity is insufficient,which provides a new idea for the joint short-term optimal dispatch of cascade hydropower and wind power. |
