Power flow results of SMIB in PSS/E do not match the hand calculations
I modeled a single machine infinite bus (SMIB) network with the following data:
Sb = 100 MVA; f = 60 Hz; P = 1 pu; Pf = 0.95; Xl1 = j0.2 pu (transmission line 1 reactance); Xl2 = jo.3 pu (transmission line 2 reactance); Generator X'd = 0.3 pu;
I added two buses, two lines and two generators. Bus 1 consisted of generator whose Pgen was set to 1 MW, Qmax=Qmin was set to 0.328 Mvar based on pf=0.95, and X Source set to 0.3. To model an infinite bus, I set the type code of bus 2 to 3 (swing) with generator X Source (pu) set to 99999. For transmission lines, pu reactances were added as Line X (pu).
I was interested in the bus 1 Voltage (pu) and Angle (degree). The results I got in PSS/E were: Voltage (pu) = 1.0004 Angle (degree) = 0.07
However, the results I got by hand calculations were different: Voltage (pu) = 1.213 Angle (degree) = 20.25
Where did I make the mistake?
- Did I model the infinite bus incorrectly?
- Did I add transient reactance X'd incorrectly?
- Or any other mistake?
Any help will be highly appreciated. Thanks.
Try to set the infinite bus generator Xsource to a small value, say 0.1 p.u.
Tried Xsource=0.1. It doesn't make any difference.
Can you show your hand calculations?
I checked the hand calculations and they turned out to be wrong. I did the calculations again, and now the results are in line with the PSS/E output.