Arc Flash Protection Case Study

Abstract— Arc flash (AF) protection is very important for all power and process industries to maintain the safety of equipment and personnel at the workplace. This describes causes and characteristics of AF faults and gives an overview of existing AF protection methods. This proposes design and development of a microcontroller based AF protection system which utilizes physical characteristics, viz. unique signature of the light, current and pressurized sound signals during AF within tap changer/switchgear compartments. The detection of physical parameters by means of a modern and newly developed sensor technology provides fast, secure, and cost-effective protection against AF, even for low/load-current arcing events. The microcontroller based arc flash protection unit including complete self-supervision
In most of the cases failures of transformer is due to the failure of OLTC. Hence the OLTC becomes the very important part of the transformer. Its failure can result in unavailability of the power transformer or total loss of the power transformer. The sudden failures of power transformer not only include the replacement cost but, safety, environmental issues and, in case a spare transformer is not directly available additional cost for not delivered power and penalty cost should also be considered. So it is become necessary to get the information about the condition of the OLTC. Conventionally maintenance of any equipment is predefined with fixed time interval by its manufacturer or supplier. Now a Modern tendency is to perform condition based rather than time based maintenance. It can reduce the maintenance cost, extend the service life of equipment and prevent possible catastrophic failure. In condition based maintenance one need to know the condition of the tap changer to determine when and what maintenance is