风电参与系统恢复的目标网架决策优化

Decision-making Optimization of Target Network Considering Wind Power Participating in System Restoration

风电参与电力系统恢复时,可为网架重构阶段提供重要的功率支持,但其不确定性也增加了恢复中系统运行的安全风险。已有研究主要侧重于“源”不确定性的建模分析,缺乏对恢复网架抵抗系统中风电功率波动能力的分析。在此背景下,提出了一种考虑风电参与系统恢复的目标网架优化方法。首先,构建了合环操作数关于支路投切的解析表达式;其次,基于极限场景法构建风电出力的多场景集以刻画风电不确定性,并以最小化合环操作数和充电无功为优化目标,建立了满足多场景集的含环目标网架优化模型。为提高求解速度,采用基于不可行割线性约束的分层迭代求解方式,通过计及直流潮流约束的含环网架优化模型求得目标网架,再校核该网架的交流潮流约束以验证目标网架的合理性。改进的IEEE-30节点系统算例验证了本文所提方法的有效性。

When wind power participates in power system restoration,it provides power support for the network reconfiguration,but its uncertainty also impacts the operation safety during restoration.The existing researches mainly focus on the"source"uncertainty modeling analysis,but lack the analysis of restoring the capability of network structure to resist wind power fluctuations.This paper proposes an optimization method for target network considering wind power participating in system restoration.Firstly,we define an analytic expression of loop-closing operands about branch switching.Secondly,we construct a multi-scenario set based on the extreme scenario method to describe the uncertainty of wind power output.And then,we establish a mixed-integer non-linear programming(MINLP)model for loop target network optimization,whose objective is to minimize the loop-closing operands and charging reactive power.Besides,in order to accelerate the calculation,we adopt an iterative solving strategy based on the unfeasible cut linear constraint.The DC power flow constraints is considered in the main optimization process,and the rationality of the target network is verified by the AC power flow constraints.An improved example of IEEE 30-bus power system verifies the effectiveness of the proposed method.