**5.9 Recommendations**

Of all the protection methods discussed above, differential current relaying is the most suited protection system for micro grid. This will enable fault location and also clearing in minimal time. Either one can have pilot lines for connecting the relays differentially (normally the feeder length in Distribution systems is not high so the cost of pilot lines also will be low) or one can locate RTUs at the two ends of each feeder and they will communicate the current magnitude, phase and direction to a central station where the fault location and tripping decisions are taken. The current measured at each end of the feeder is applied to Directional Over current

relay with fixed operating time to provide backup protection. This system will not require any changes either in configuration or settings for faults in the micro grid or in the main grid. Also this is not affected by the number and location of DERs and whether the micro grid is connected or isolated from the main grid.
