基于蒙特卡洛和虚拟节点法的电压暂降正反分析

Forward and backward analysis of voltage sag based on Monte Carlo method and virtual node method

随着现代精密电气设备的广泛使用,电压暂降问题已成为电力部门日益关注的重点。传统对电压暂降的研究方法只局限于因故障而引起PCC点电压暂降的情况,或者根据PCC点的电压暂降设定阈值反推故障的位置。两者方法各有优缺点,将两种研究的思路整合起来,以IEEE30节点标准测试系统为模型,从正反两方向研究电压暂降的相关特性。正向研究基于蒙特卡洛法和PSCAD/EMTDC实现对电压暂降进行自动随机仿真计算,得到各敏感PCC点处电压暂降特征参数和电压暂降概率分布。反向研究利用虚拟节点法来建立PCC点在各种类型故障下的电压幅值和故障位置的关系式,设定电压的阈值反推出对应的故障位置,将所有故障位置连接起来得到相应的电压凹陷域。两种方法的结合,为电压暂降防控措施提供更多的理论依据。

With the extensive use of modern precision electrical equipment,the problem of voltage sag has become an increasing focus for the electric power sectors. The traditional research methods for voltage sag are limited to few aspects,the PCC voltage caused by failure,or the location of the failure by setting the threshold according to the voltage sag of PCC. Both methods have their own advantages and disadvantages. By integrating the two methods and taking the IEEE30 node standard test system as the model,the related characteristics of voltage dips from both forward and reverse directions are studied in this paper. The forward research is based on Monte Carlo and PSCAD/EMTDC to realize the automatic random simulation of voltage sags. The voltage sag characteristic parameters and voltage sag probability distribution at each sensitive PCC point are obtained. The reverse research uses the virtual node method to establish the relationship between the voltage amplitude and fault position of PCC points under various types of faults, and set the threshold of voltage to counteract the corresponding fault location as well as connect all fault locations to get the corresponding voltage sag area. The combination of the two methods can provide more theoretical bases for the prevention and control measures of voltage sag.