An adaptive protection scheme for small scale microgrids based on fault current level

Abstract

With the growing of the “Microgrid” concept in the modern world, new protection systems are required. This protection system should be handled the all configurations and all conditions of the microgrids and suitable for small scale less expensive microgrids. This paper proposed a reliable, online, adaptive and accurate method for microgrid protection by using fault current level of the system considering the modes of operation, dynamic nature of the Distributed Generators (DGs) and different types of the loads. This is an adaptive protection scheme for a microgrid; where a Microgrid Central Protection Unit (CPU) monitors the microgrid continuously using a communication medium, whenever fault is detected in the network, the relay settings of the microgrid are altered adaptively based on instructions issued by CPU. This method can be operated accurately by estimation fault current level of the Microgrid at the instant and using that relay tripping current at any disturbance and can be calculated at any condition. By using this protection strategy, can create self-operated microgrid and can avoid human interference to the microgrid operation, design and calculation.