Conventional Protection Approach for Microgrids Considering All Types of Phase Faults for both Grid Connected and Islanded Mode /

Abstract

Microgrids are capturing the attention of power system designers due to their potential to operate in island mode, separating from the utility grid in the event of a catastrophic breakdown. The exploitation of fossil fuels for power production has detrimental effects on the environment, but microgrids are environmentally beneficial since they promote the use of renewable energy. Protection design is a noteworthy attention during planning of Microgrids to ensure their reliable functioning. Because DERs are present inside Microgrids, direction of current flow is not traditional (from utility towards load). Therefore, smart protection strategy is necessary. Following the transition of Grid Connected to Islanded-Mode, there is a significant change in the amplitude of fault currents. This change has an impact on the protection system since the overcurrent relays inside microgrid are adjusted with higher pick-up currents values. This work presents a reliable, inexpensive, and effective Current Controlled UV (Under-Voltage)protection system. The system utilizes locally sensed current and voltage to make tripping decisions, ensuring protection in both island and grid-connected modes. Importantly, this system does not rely on any communication channels. This security method has been tested on the 9-Bus Canadian Urban Benchmark Distribution System, which was designed using ETAP.