Hello 

First of all Congratulations.

For GATE  EC Central PSUs were- Iocl,Ongc,Gail, Ntpc,, Hpcl.

For getting into PSU only gate score is not enough if your rank is above 100.There is high compettition and 

since the students scoring rank below 100 have high chances because the weightage of gate marks is less,there are tight chances although there are some PSU's you can apply.

As per your rank you can opt for IOCL,ONGC.HPCL.

Although the final decision is taken after the interviews 

i hope it help's.

GoodLuck..