We are facing a peculier problem of Neutral to Earth voltage high.
2MVA Transformer 11KV/0.433KV , Dry type transformer is installed with LT drives.
When Drives are running in Regenerative Mode Neutral to Earth voltage measuered at the body of the transformer is earlier around 30 V.
We have provided few more additional earthpits for body & Neutral of the transformer , now value has come down to 12 V.
This voltage is measured at the neutral & body of the 2MVA transformer.
What could be the problem & how to reduce this Neutral to Earth voltage to a safe level