Transformer models in EMTP/ATP
Transformer models in EMTP/ATP
Transformer models in EMTP/ATP
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Magnetiz<strong>in</strong>g core model<strong>in</strong>g<br />
• Must be considered <strong>in</strong> the follow<strong>in</strong>g studies<br />
• <strong>Transformer</strong> energization studies<br />
• Load rejection studies<br />
• Switch<strong>in</strong>g of transformer term<strong>in</strong>ated l<strong>in</strong>es<br />
• Ferroresonance studies<br />
• CT saturation<br />
• CCVT model<strong>in</strong>g<br />
• No-load losses <strong>in</strong>clude:<br />
• Eddy current loss and<br />
• Hysteresis loss<br />
• Could be represented with a resistance Rm <strong>in</strong> parallel with the<br />
nonl<strong>in</strong>ear magnetiz<strong>in</strong>g <strong>in</strong>ductance, or<br />
• As external, nonl<strong>in</strong>ear (hysteretic) <strong>in</strong>ductance connected to a<br />
low voltage w<strong>in</strong>d<strong>in</strong>g<br />
Hybrid model - XFMR<br />
• The user can construct the transformer model on<br />
three sources of data:<br />
– Design parameter: specify geometry and material<br />
parameters of the core and w<strong>in</strong>d<strong>in</strong>gs.<br />
– Test report: standard transformer tests.<br />
– Typical values: typical values based on the voltage and<br />
power rat<strong>in</strong>gs.<br />
• The model <strong>in</strong>cludes:<br />
– an <strong>in</strong>verse <strong>in</strong>ductance matrix for the leakage description,<br />
– frequency dependent w<strong>in</strong>d<strong>in</strong>g resistance,<br />
– capacitive coupl<strong>in</strong>g,<br />
– and a topologically correct core model with <strong>in</strong>dividual<br />
saturation and losses <strong>in</strong> legs and yokes.<br />
10 / 19<br />
11/6/2012