about transformer ....please help

[jaser2014]

Hi all

This is jaser, I just graduated and I'm working in radio station(mid-voltage 11kv ). most equipments feed by 11kv and our load reach 4Mw

so we have two supply for our station:
1- from Public electricity (33kv) and we switch it to 11kv by transformer 33kv/11kv.
2- from our generators give 11kv.

now public electricity company wants to change the line from 33kv to 13.8kv

so our options is:

1- change all equipments from 11kv to 13.8kv and take the power directly from the electricity, no need transformer.
(this option seems impossible, it will cost alot).

2- change our transformer from 33kv/11kv to 13.8kv/11kv to match new feeder (13.8kv).
( it seems reasonable)


My question To experts


What would you like to Recommend


I'm worried if we change the transformer.
will the transformer work fine or we will face troubles with heating and efficiency and we need to change the transformer time to time.

please help.

 

[FPelec]

dear jaser,
the most simple solution is to change the existing 33kV/11kV transformer with a new 13.8/11 kV one. If the neutral grounding is not a concern you could use an autotransformer, being the co-ratio extremely favorable.
New autotransformer losses will probably be very lower if compared to the existing transformer.


Si duri puer ingeni videtur,
preconem facias vel architectum.

 

[jaser2014]

I would thank your kindness sir and thank you for helping.

Have a great day FPelec

 

[squeeky]

Dear Jasper, The 13.8kV to 11kV auto transformer will be the less expensive option. You will need to review all your protection. If you select an auto transformer understand that you will have a direct connection to your utility. All disturbances will be seen on your circuits as there is no inductive barrier. It seems strange that they wish to drop the voltage, thus increasing the current and therefore the voltage drop on existing lines and again increased losses and efficiency. Who will end up paying for these losses? The consumers. Most areas are increasing voltages for these reasons.