"MVA/Current expressed as MVA"

asked 2025-09-04 00:01:54 -0500

Yoyo
33 ●13 ●15 ●20

Hello everyone

Can someone please explain to me the meaning in diagram》properties the concepts of "MVA/Current expressed as MVA"? What is the difference between these definitions and when is it correct to define each of them for "Transformer/Non transformer branches?"

I would love an example of the differences.

Thanks!

answered 2025-09-08 08:26:02 -0500

likethevegetable
101 ●13 ●18 ●21

T-Lines are often given an MVA rating because it's easier to relate to the bulk transfer of power and is invariant between nominal voltage levels. But thermal limits of T-Lines are based on current because that's what heats up the metal. So if you express % rating of line based on an MVA flow, the actual current will differ depending on the voltage. Using "Current as MVA" will account for this and give you want, generally speaking.