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A time-domain model of an AC electric arc furnace (EAF) was developed for power system (flicker) planning studies. The proposed model was implemented in the Electro Magnetic Transient Program (EMTP), and it focuses on the behavior of the EAF during the early stages of the melt cycle, thus providing an accurate prediction of the short term flicker created by the EAF, specifically [P.sub.st99%.]. The primary advantages of the proposed model over existing models are: 1) it uses system data that is readily available to the planning engineer; 2) it is a three phase model and can accurately model imbalance and predict flicker at the point of common coupling (PCC) as well as remote buses in the power system; and 3) its accuracy has been verified using synchronized flicker measurements of an actual EAF. Existing time-domain EAF models that are used in flicker planning studies require measurement or statistical data that is difficult to obtain during the planning stages of a project. Frequency domain methods are a popular means of estimating the flicker created by an EAF; however, when these methods are used in flicker planning studies, the operational uncertainty of the EAF introduces error into the calculations. Also, in many cases, frequency domain methods struggle to accurately predict the flicker level at buses remote from the PCC. Thus, a time-domain EAF model which can accurately predict [P.sub.st99%] at points of interest and uses readily available system information is needed. The following paper describes such an EAF model. Validation of the proposed model is performed by comparing simulation results with flicker measurements of an actual EAF that were time synchronized using global positioning systems (GPS). Index Terms--Flicker, flicker measurement, flicker transfer coefficient, furnaces, power quality.

Induced voltage and current in a deenergized transmission line caused by other lines nearby can be caused by electric-field and magnetic-field induction. These voltages and currents present a serious work hazard for line-crew personnel. Proper understanding of the phenomenon involved and identification of the associated hazards are necessary to safely perform deenergized line work. The purpose of this paper is to clarify some of the misconceptions that have been prevalent in the industry for many years as well as to expand on the test data available in literature. This paper discusses, in simple terms, the relevant parameters that affect the magnitude of the induced voltage and current as well as the work hazards they create. Index Terms--Electromagnetic induction, grounding, safety.

In recent years, a large number of electric utilities have been implementing fuseless split-wye grounded capacitor banks in lieu of the traditional externally fused bank. This change in philosophy has forced many protection engineers to research new methods of calculating the quantities needed to apply unbalance protection. This paper presents a novel method of calculating the unbalance current produced by fuseless capacitor unit failures as well as some general background information regarding fuseless split-wye grounded capacitor bank technology and unbalanced protection. Index Terms--Power capacitors, power system protection.