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.
