Flexible Power Planning Considering Wind Power Integration

Nowadays,under the initiative of the energy revolution and environmental protection policy,wind power develops rapidly.Due to its randomness,volatility and anti-peak-characteristics,the large-scale wind power integration on power system proposes more acute challenges to security and stable operation.Therefore,the phenomenon of abandoned wind often appears to maintain the stability of the power grid,which causes the serious waste of wind resources.Since the traditional power system is mainly based on coal-fired units whose regulation performance is not enough,more flexible backup energy is needed to meet safety and economy of power system operation when large scale wind is integrated.In view of the above problems,the energy storage system(ESS)and interruptible load(IL)are considered to improve the flexibility of system operation.In order to reflect wind anti-peak-characteristics,K-means clustering method is used to cluster the load and wind speed sampled data,dealing the uncertainty between load and wind power output.Above all,a generation expansion planning model integrating wind,thermal power,ESS and IL is established.The objective is to minimize the total construction and operation cost,and a simplified model of unit commitment model is adopted to reduce the computational difficulty.The objective are subject to output constraints of generations,constraints of line capacity,DC power flow equation,constraints of system active power balance,power balance constraints,unit reserve constraints,climbing capacity constraints,IL called time and capacity constraints,ESS power and capacity constraints of charging and discharging and so on.General Algebraic Modeling System(GAMS)is applied to solve the proposed mixed integer linear programming model.Impacts of ESS and IL on the system planning and operation are investigated and the flexibility index of system integrating wind power is set up.Numerical examples demonstrate the effectiveness of the proposed approach.