Recent content by supra33202

I am selling the following books and reference materials. All items' condition is like-new. 1. Electrical Machines, Drives and Power Systems (6th Edition) 6th Edition [Theodore Wildi] - $104 2. Power System Analysis and Design, Fifth Edition 5th Edition [J. Duncan Glover, Mulukutla S. Sarma...

I understand that the "average power consumption" is just the area under the curve (graph). 1 square = 25 kW Time interval 1: 25kW Time interval 2: 25kW + 25kW (0.5) = 37.5 kW Time interval 3: 25kW + 25kW + 25kW (0.5) = 62.5 kW Time interval 4: 25kW + 25kW = 50kW But for " "Max Demand at...

I read the solution but I don't understand how to get the "Max Demand at Start of Interval (kW). Please advise. Thanks,

I also need help on this one. Could you confirm my diagram (attachment) is correct? Thanks!

1) Could you confirm my calculation (attachment) is correct? 2) I understand that the question doesn't ask about the angle. But if I set Van at angle 0 deg, should the In (neutral current) at angle -86.57 deg? Notes: a) I also think that current conjugate should be considered (for single...

@Zach Stone, P.E. Thanks for the help!

@Zach Stone, P.E. I am working on Fault Current Analysis quiz question 9 at electricalpereview.com. And I am trying to use PU method to solve it. Set Vb=4160V, Sb=1.5MVA Zg, pu (Zpu at generator) = 0.079 pu * (1.5MVA/50MVA)=0.00237pu Zx, pu (Zpu at transformer) = 0.075pu Since Zg, pu is...

@Zach Stone, P.E. Could you help me with this one? + In your website electricalpereview.com Video Example 8 - Generator and Transformer Per Unit Method, it seems like you also ignore the whole "voltage base old and voltage base new" term. Zg,new = 5.6% (20MVA/55MVA) = 0.0206 pu Are the...

@Zach Stone, P.E. Thanks!

Question: Does the transformer contribute to the fault current in this case? If yes, why and how? Thanks!

This is from Fault Current Analysis quiz at http://www.electricalpereview.com. @Zach Stone, P.E. The fault is between the generator and the transformer. Does the transformer to the fault current? If yes, why? My solution: Since the fault happens at the upstream of the transformer, only the...

I am trying to use the MVA method. Sg = 200MVA/.25 = 800MVA Stx1 = 200MVA/.12 = 1666.7 MVA Since they are in series, treat them as resisters in parallel circuit. S=((1/800MVA) + (1/1666.7))^-1 = 540.5MVA Isc = S / sqrt(3) * V = 540.5 MVA / sqrt (3) * 230kV = 1356.8 A Graffeo's answer is I...