A novel method for estimating voltage flicker

This investigation develops an enhanced method for estimating the voltage fluctuation (/spl Delta/V/sub 10/) of the electric arc furnace (EAF). The method not only considers the reactive power variation but also the active power variation in calculating the estimated /spl Delta/V/sub 10/ value of ac and dc EAFs. This study also considers field measurements of ac and dc EAFs. The results reveal that the estimated /spl Delta/V/sub 10/ value is significantly smaller than the observed value. The conventional way of estimating /spl Delta/V/sub 10/ is ineffective. The survey results demonstrate that variations of active power and reactive power of EAFs are strongly alike. Meanwhile, an /spl Delta/V/sub 10/ estimate must account for the effect of active power variation. However, this study proposes a maximum apparent power fluctuation method that can yield a more accurate /spl Delta/V/sub 10/ estimation than the conventional method.

I. Introduction

Voltage flicker associated with an EAF is evaluated in two main ways around the world [1]. The first is flicker meter, which is the IEC standard and has been established by the UIE [2]. The other is meter, which is established by the Japanese Technical Committee [3]. Moreover, is the method presently used by the Taiwan Power Company (TPC) and, thus, is applied herein. Voltage flicker causes sudden flashes of luminosity in fluorescent lamps and electric lights, and disturbances in other electrical equipment [4], [5]. Voltage flicker problems have long existed in many of the distribution areas served by TPC, especially those that include steel plants that operate arc furnaces [6]–[8].