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Switching transients associated with circuit breakers have been observed for many years. Recently, this phenomenon has been attributed to a significant number of transformer failures involving primary circuit-breaker switching. These transformer failures had common contributing factors such as the following: 1) primary vacuum or SF-6 breaker; 2) short cable(More)
Modern sodium chlorate or sodium hypochlorite-making processes (commonly known as “bleach”) take salt and water through an electrolytic process. The electrolytic process requires a significant amount of dc power. Bleach production plants, equipped with rectifiers, can generate potentially damaging harmonic currents if not mitigated or(More)
An electric arc furnace, a ladle melt furnace, a single-tank vacuum degasser, and a four-strand continuous caster comprise this new melting and casting operation that supports a rod and bar-in-coil rolling mill. This paper describes the design, analysis, and operation of the electrical distribution system for these modern electric arc furnace and ladle melt(More)
During commissioning of a large data center, while switching medium-voltage circuit breakers without any appreciable load, several potential transformers failed catastrophically. A detailed investigation, including a computer simulation, was performed. Ferroresonance produced by switching transients associated with opening and closing the vacuum breakers(More)
Switching transients associated with circuit breakers have been observed for many years. With the widespread application of vacuum breakers for transformer switching, recently, this phenomenon has been attributed to a significant number of transformer failures. Vacuum circuit breaker switching of electric arc furnace and ladle melt furnace (LMF)(More)
The value proposition for the installation of power factor (PF) correction (PFC) to avoid costly utility penalties is easily understood. The attractive payback of such PFC opportunities often pushes the project ahead without engineering considerations. In the case of medium-voltage PFC, lack of upfront engineering can lead to unexpected consequences in the(More)
The trend in industry to replace motor-generator sets with static rectifiers often results in soft voltage and harmonic distortion issues which must be corrected after the fact that the distribution system not only experiences increased reactive load with the added rectifier transformers but also generally experiences a loss in reactive power when the(More)
To date, many papers have been written about various concepts in power system grounding, explaining the application, advantages, and disadvantages of each of the solidly grounded, resistance-grounded, and ungrounded systems. The purpose of this paper is not to explain the theory behind the aforementioned concepts but rather substantiate them with actual(More)
The advantages of a Static VAR Compensator (SVC) for electric arc furnace (EAF) and ladle melt furnace (LMF) applications are well known. The SVC minimizes the impact of the EAF and LMF on the utility as well as improves the efficiency of both furnaces. In this application, it was desirable to quantify the performance of the SVC. This paper describes power(More)
This steel maker is upgrading the electric arc furnace (EAF) melt shop to increase production and improve metallurgical quality of their product. The increased electrical load and harmonic generation for the new furnace operation necessitated the installation of a static var compensator (SVC) to meet utility interconnect requirements. This paper describes a(More)