基于电压偏差机会约束的分布式光伏发电准入容量研究

Research of Permitted Capacity of Distributed Photovoltaic Generation Based on Voltage Deviation Chance Constrained

针对光伏发电并网输出功率随机性及相关性导致配电网节点电压越限的不确定性,提出基于电压偏差机会约束的分布式光伏发电并网准入容量规划方法。首先,建立考虑光伏相关性的配电网概率潮流计算模型,将Nataf变换与基于矩法的三阶多项式正态变换相结合处理光伏的相关性,采用多重积分理论和Gram-Charlier级数展开得到配电网节点电压分布;然后,以最大化光伏发电并网准入容量为规划目标,电网电压不越限为机会约束,建立基于电压偏差机会约束的光伏并网准入容量计算模型,利用改进的随机权重粒子群算法对模型进行求解。仿真算例结果表明该方法能够提高光伏并网容量,使配电网运行满足电压偏差不越限。

For the voltage uncertainty of distribution network node is caused by the random and correlation of photovoltaic(PV)output power,in this paper,the planning method of PV permitted penetration based on the voltage deviation opportunity constraint is proposed.Firstly,the PV probabilistic load flow model is established,which units Nataf transform and third-order polynomial normal transformation based on the moment method to solve the correlative output of PV,and the multiple integral method and Gram-Charlier expansion are implemented to obtain the distribution of voltage as the chance constrained condition.Then,under the target of maximum PV permitted penetration capacity and voltage deviation opportunity constraint,the planning model of PV permitted penetration capacity based on the voltage deviation opportunity constraint is established,and the improved random weight particle swarm optimization(PSO)is used to solve the planning model.Simulation results suggest that the proposed method can enhance PV permitted penetration capacity,and make distribution network voltage deviation meet the demand.