Fault Distribution Modeling Using Stochastic Bivariate Models for Prediction of Voltage Sag in Distribution Systems

Abstract

This paper presents a new method regarding fault distribution modeling for the stochastic prediction study of voltage sags in the distribution system. 2-D stochastic models for fault modeling make it possible to obtain the fault performance for the whole system of interest, which helps to obtain not only sag performance at individual locations but also system sag performance through system indices of voltage sag. By using the bivariate normal distribution for fault distribution modeling, this paper estimates the influence of model parameters on system voltage sag performance.The paper also develops the modified SARFI X regarding phase loads that create better estimation for voltage sag performance for the distribution system.Index Terms-Bivariate normal distribution, distribution system, fault distribution modeling, phase loads, power quality (PQ), stochastic prediction, voltage sag frequency.

Analysis of Event Sequences in Power Distribution Systems

“…Artificial neural networks (ANNs) are employed to monitor the states of some components in power networks, such as switchgears and transformers, with the aim of detecting and alerting the operator before a catastrophic fault occurs. Fault distribution modelling for stochastic prediction of voltage sags in power networks are developed in [12] and [13] with the goal of predicting the performance of the power network under transient conditions. A fault diagnosis model, based on data mining of sequences of events (SOE), for fault diagnosis of high-voltage transmission line systems (HVTLS) is presented in [14].…”

Effect of protection device coordination on voltage sag characteristics of distribution networks

“…is the rated current of the relay n, K 1 two coefficients to fit the relay performance speed based on manufacturer specification T m fault starting time R s pre-fault resistance, respectively.…”

“…According to IEEE-1159-1995, voltage sag is defined as a reduction of RMS voltage in the range of 10%-90% of the rated amplitude during 0.5 cycles to less than one minute [1]. The main reason for the occurrence of voltage sag is the temporary increment of network current.…”

“…The software has extensive modeling capabilities and additional important features besides its abilities in the computation of transients. ATP-EMTP are also used world-wide for switching 1 …”

Analysis and Design of a DSTATCOM Based on Sliding Mode Control Strategy for Improvement of Voltage Sag in Distribution Systems

“…The main causes of voltage sag include short circuit fault, starting large induction motors, sudden load variations, and energization of the transformer [7,8]. Voltage sag is a temporary event and its causes are also considered as a temporary low or medium frequency phenomenon [9,10]. Nowadays, with high demands and increases in sensitive equipment, voltage sag is not tolerated in power systems, and various methods have been applied to decrease it [11,12].…”