Magnetisation Current Calculation
Magnetisation Current Calculation
(OP)
Hi all,
I have a transformer with the following information:
3150kVA, 3.3kV/0.415kV, Yd11, Z=6.5p.u.
The maximum magnetisation current at 0.02 seconds is 67420Ampere. How can I calculate this value as I have no idea about this.
I have a transformer with the following information:
3150kVA, 3.3kV/0.415kV, Yd11, Z=6.5p.u.
The maximum magnetisation current at 0.02 seconds is 67420Ampere. How can I calculate this value as I have no idea about this.






RE: Magnetisation Current Calculation
The Magnetising Current is the current to overcome the No-Load losses in the Transformer.
RE: Magnetisation Current Calculation
This magnetizing phenomenon occurs during energization of transformer and other apparatus. In the worst-case scenario, a value of flux approaching 300 per cent of nominal can be attained, thus causing appreciable saturation of the magnetic core and a massive inrush magnetizing current. The transient component decays rapidly during the first few cycles and more slowly thereafter. The damping is caused by the R/L factor, which is initially high due to the core saturation (L low) and decreases as the core becomes less saturated.
Suggestion: search in this site and the Internet. There are plenty publications similar to the enclose samples:
Thread238-10885
http://www.sandc.com/webzine/111102_1.asp
http://www.sandc.com/webzine/012003_1.asp
http://pm.geindustrial.com/FAQ/Documents/T60/GER-4001.pdf
RE: Magnetisation Current Calculation
you are talking about Inrush Currents or Magnetizing Currents?
RE: Magnetisation Current Calculation
I believe that steady state magnetizing current is typically in the range of 10% of full load current. It can of course be determined by measuring the primary current when there is no load on the secondary. Also can be determined from factory test data