Over current relay coordination of modified IEEE test systems with distributed generation using genetic algorithm approach

Abstract

The development of smart grid technology leads to the addition of more and more distributed renewable energy resources like wind power, solar power etc. to the grid. The distributed generating sources are usually connected in the load side and the major protective device in the distribution side is the Over Current Relay (OCR) which is the effective and economic protection scheme. The coordination of over current relays is generally studied based on fixed network topology and the generating sources. The dynamic nature of renewable energy sources results in the variation of short circuit level, bidirectional power flow etc and hence the protective devices have to adapt to these changes. The artificial intelligence technique helps to change the relay settings according to the variation in wind velocity, number of wind generators put in service etc. In this paper coordination of over current relay is carried out by genetic algorithm and optimum time dial settings is found out according to varying wind power penetration.