International Journal of Engineering Research in Electrical and Electronic Engineering (IJEREEE)

Investigation of Modernized Numerical Relay with Watchdog Timers to Achieve Reliability

Author : Asha.K ¹ Meghana.S.N ² Vijaya Kumara.M.G ³ Teli Rekha Appasaheb ⁴ Manjunatha S ⁵

Date of Publication :7th November 2016

Abstract: The recent trend in protection has been a shift to numerical relay protection techniques, thanks to the development using the single chip digital signal processors with high crunching capability, which has made it possible to design digital filters in real time. In the protection field, numerical techniques have got first application to line protection, and other complementary functions like fault locator, disturbance recorder & auto-reclosing. The present work describes latest salient features of the numerical protection technology, different multifunctional relays going to be installed in modern power system protection and their methods of protection. Malfunction of relay protection is one of the main causes of the heavy failures that periodically occur in power systems all over the world. Thus the reliability of a power system depends on the reliability of relay protection in many respects. Watchdog timers are an excellent way to insure that a microprocessor based system continues to operate unattended if occasional failures occur. The way that a watchdog timer does its job is to monitor a particular signal sent by the microprocessor.

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