配电网电压稳定性研究

Research on Voltage Stability of Distribution Networks

基于配电网潮流解的存在性,提出了一种能够反映负荷分布与电压稳定性关系的电压稳定判据,即第一类电压稳定判据,指出了第一类电压稳定判据是配电网电压稳定的必要条件但不是充分条件,定义了配电网电压稳定裕度和电压抗扰动安全距离等指标,分析了基于负荷–电压特性的第二类配电网电压稳定判据存在的问题,得出了配电网电压稳定应该满足2类电压稳定判据的结论。仿真计算结果验证了上述分析的正确性,说明上述电压稳定指标确实可以反映配电网的电压稳定性与抗扰动能力。

Based on the existence of power flow solution of distribution networks, the first class voltage stability criterion that can reflect the relation between load distribution and voltage stability is proposed. It is pointed out that the first class of voltage stability criterion is the necessary condition for voltage stability of distribution networks but not the sufficient condition, The indices such as voltage stability margin of distribution networks and safe distance of voltage anti-disturbance are defined and the problem of the second class voltage stability criterion in existing load-voltage property based on voltage stability criterion for distribution networks is analyzed. It is concluded that the two classes of voltage stability criterion should be simultaneously satisfied to keep voltage stability of distribution networks. The correctness of above-mentioned analysis is verified by case study, and the case study results show that the proposed criterion can be used to evaluate the voltage stability and counter-disturbance capability of distribution networks indeed.