Analysis of Neutral Ground Resistance Behavior of Fourth Refinery Gas Power Plant in Real Short Circuit Faults

Rahman Dashti; Abbas Baghbani; Gholam Reza Ghanbari

The Fourth Refinery is one of the largest refineries in Iran due to its vast area as well as its extensive equipment. This refinery includes three gas phases consisting of six operational trains. The vastness of this refinery combined with its involved processes as well as equipment frequency and complexity make it stand out among other refineries, so much so that every minute a train has to be turned off would lead to irreparable and heavy financial losses. The neutral points of the 11kV/33kV transformers supplying electricity to The Fourth Refinery are earth-connected through NGRs (neutral ground resistors). The transformer NGRs are equipped with tap changers which are damaged and burned without the utilizer’s knowledge in the event of a short circuit. Therefore, any kind of short circuit in the power system of The Fourth Refinery would damage the protective NGRs and CTs, thus destroying the system protection units, which might in turn lead to tripping of the refinery as a whole. For this reason, an attempt was made in the present article to solve this problem by conducting simultaneous theoretical calculations, simulations, and practical tests.

Select Volume / Issues:

• Volume 6,Issue 3, May 2015

Year:

2015

Type of Publication:

Article

Keywords:

Charging Current; Fourth Refinery Gas Power Plant; Neutral Grounding Resistors; Practical Tests; Single Phase To Ground Short Circuit; Simulation in MATLAB

Journal:

IJECCE

Volume:

6

Number:

3

Pages:

361-369

Month:

May