Answer / rockyxyz

if i am correct NGR is Neutral grounding resistance. NGR
are used to restrict the earth fault current during fault
condition below a certain value. this is done for high
voltage genertors coz due to high voltage & low windng
resistance fault current is very high and the windings are
not designed to carry such a large current so it is the
place where NGR comes to play

Answer / mahadeva annigeri

NGR USED IN 11KV GENERATING STATION IS TO LIMIT THE FAULT CURRENT WITHIN THE SPECIFIED LIMIT,Ex: AS PER FORMULA I=V/R,V=11KV.R=63OHM.SO 11000/1.732/63=100A,NGR WILL CONTROL UP TO 100A ONLY BECAUSE GENERATOR IS CONNECTED WITH GRID (SYNCHRONIZED CONDITION)HEAVY FAULT CURRENT MAY OCCURED IN LINE,THAT FAULT CURRENT MAY DAMAGE WINDING INSULATION THATISWHY NGR IS USED TO PROTECT THE GENERATOR FROM HEAVY FAULT CURRENT.I THINK SO

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