基于广域信息的电压稳定在线评估与无功电压协调控制方法

Online Voltage Stability Assessment and Voltage-reactive Power Coordinated Control Method Based on Measuring Information of Phasor Measurement Unit

为提升系统全局电压稳定性,保证电网安全运行,亟需研究电网电压水平实时监测和系统无功电压动态控制方法。本文采用一种基于广域量测信息且兼具良好准确性与线性度的静态电压稳定指标,并结合综合隶属度函数法建立了综合考虑系统电压稳定裕度及系统网损的多目标最优潮流模型。该模型可对电压稳定裕度较低区域相关支路的电压稳定指标分配更高的优化优先级,以实现有效提升系统全局电压稳定性的目的。同时根据系统的不同运行工况确定目标函数权重系数的取值,以实现对系统运行经济性和电压稳定性重要程度的区分。采用IEEE 14节点系统和IEEE 57节点系统,应用Matlab编程验证了本文提出的无功电压控制模型及控制策略的合理性和有效性。

To improve system global voltage stability and ensure operation security of power system,it is urgent to study online real-time monitoring of system voltage level and the dynamic voltage-reactive power coordinated control method.In this paper,by using voltage stability index that has ideal accuracy and linearity based on the measurement information of PMU,the multi-objective optimal power flow model is proposed by considering system network loss and voltage stability margin based on synthetical membership method.This model can effectively improve the global voltage stability by assigning higher optimization priorities for branches in low voltage stability area. Meanwhile,the weight indexes of objective function are determined to distinguish the important degree of system economic efficiency and voltage security according to different system operation status.In the end,simulations are carried out in IEEE-14 and IEEE-57 bus systems and the result verifies the correctness and the effectiveness of the proposed voltage and reactive power control model and strategy.