Offshore oil and gas platform transient over-voltages from ground fault on ungrounded system

Abstract

The High Resistance Ground was used at the oil and gas platforms because of the main reason of not having the process in the facility interrupted. There are cases where main high voltage contactor has tripped and disabled the process at satellite platforms due to the lightings module grounded. This is unacceptable to the daily production. In this paper it will discuss on the electrical distribution load flow analysis, capacitive charging system for the HRG designs and the single phase to ground fault control which is offered by the HRG systems. In the oil and gas platform, there is always a case where the ground fault occurs and causes disturbance to the process. With the 3 Generators (Solar Centaur 3125 MVA) power for the overall electrical distribution, all the equipment on the buses is prone to the faults. It has always been the challenge to control and eliminate or reduce the ground faults. The determination of the total system charging current (Ic) is important and thus determining the value of resistor that is able to limit the fault to ground. The limit of current is about 5-10A. This investigation also will compare and analyze the line to ground faults. Symmetrical components are usually widely used for the study of fault calculations.