考虑线损灵敏度一致性的外网静态等值模型

Static Equivalent Model of External Network Considering Consistency of Line Loss Sensitivity

目前的网络等值模型均不能保证等值前后线损灵敏度的一致性,不适用于线损分析,针对该问题,提出考虑线损灵敏度一致性的外网静态等值模型。首先,分析传统WARD等值应用于线损分析的弊端,提出适应于线损分析的等值模型新理论,该新模型通过在边界节点外接虚拟等值发电机节点,平衡等值前后线损灵敏度的误差,可保证等值前后线损对内部节点注入有功功率、注入无功功率、节点电压幅值和电压相角4个灵敏度的一致性;然后基于改进的雅克比矩阵计算线损灵敏度的表达形式,并基于等值前后潮流一致性原则、线损灵敏度一致性原则,求取等值模型参数。采用IEEE 39节点系统及甘肃实际电力系统进行仿真计算,验证文中等值模型的正确性和实用性。

Current network equivalent models can not guarantee consistency of line loss sensitivities before and after equivalence,thus not suitable for line loss analysis.To solve this problem,a static equivalent model of external network considering consistency of the line loss sensitivities is proposed.Firstly,based on analysis of the drawbacks of traditional WARD equivalent model,a new equivalent model theory is proposed.The new model balances the sensitivity errors of line loss before and after equivalence by connecting virtual equivalent generators outside the boundary nodes,so as to ensure that the line loss sensitivities to active power,reactive power,node voltage amplitude and voltage phase angle maintain unchanged.Then the expression of line loss sensitivities is calculated based on improved Jacobian Matrix,and the parameters of the equivalent model are obtained based on the consistency principles of power flow and line loss sensitivities.IEEE39 bus system and actual Gansu power system are used to verify correctness and practicability of the equivalent model proposed in this paper.