Current Limiting Reactor 3

[kingi]

I have two questions:
1. Where can I find the X/R ratio of a 3ph, 12.6 kV, 5%, 600A reactor?
2. I calculated the MVA rating of this reactor as follows:
1.73x12.6x600/1000=13.1 MVA. Is this correct?

Thanks,
kingi

 

[mpparent]

1. The manufacturer
2. Yes

Mike

 

[kingi]

Thank you for your reply. I took the information from a drawing where the manufacturer was not mentioned. I wonder what would be the approximate X/R ratio for a similar series reactor?

Thanks,
kingi

 

[scottf]

Kingi-

It's impossible to accurately speculate. The Q-factor (X/R) varies substantially with design and even within designs of the same manufacturer.

 

[dpc]

Conrad St. Pierre's book, "A Practical Guide to Short-Circuit Calculations", has some curves in the Appendix for typical air core reactor X/R, depending on the conductor material.

For a 13.1 MVA reactor, the range for X/R is on the order of 40 to 70.

 

[kingi]

Thank you all. I didn't think the X/R ratio was that high.

kingi

 

[dpc]

If you know what the conductor material is, I can give you an equation for an approximate calculation of X/R.

It will still be quite a few watts of heat loss when you run the numbers out, since you're dealing with the square of the current.

 

[scottf]

DPC-

I seriously question that table you reference based on conductor material as being accurate (of course 40-70 is a huge range). There are many different types of winding and conductor profile configurations for air-core reactors...and i say that as someone who works for a reactor configuration.

Just my $0.02 worth.

 

[dpc]

scottf,

It's the same chart and equations that GE has referenced for years, I think.