in the area where i live, there are a lot of power transformers station where the neutral is not grounded, (transformers 3*230volt sec without neutral)
the power company like to generate a neutral en ground it...
this is easy to do with e Y transformer.
th idea is to build smal Y transformers, max 25 ams/phase and ground them
but if there is a failure , we like to limit the Ground Current for safety
(pls do not view this local... it is for use over a larger area)