Power Systems The voltage and current instantaneous values are given as 5 sin (ωt + 30°) pu and 2 sin (ωt - 15°) pu respectively. Find the per unit active power? 3.535 pu 7 pu 5.353 pu 5 pu 3.535 pu 7 pu 5.353 pu 5 pu ANSWER DOWNLOAD EXAMIANS APP
Power Systems A lossless power system has to serve a load of 250 MW. There are two generators(G1 and G2) in the system with cost curves C1 and C2 respectively defined as follows: C1 = PG1+0.055P²G1 C2 = 3 PG2 + 0.03 P²G2 Where PG1 and PG2 are the MW injections from generators G1 and G2 respectively. Thus, the minimum cost dispatch will be PG1 = 100 MW and PG2 = 150 MW PG1 = 250 MW and PG2 = 0 MW PG1 = 150 MW and PG2 = 100 MW PG1 = 0 MW and PG2 = 250 MW PG1 = 100 MW and PG2 = 150 MW PG1 = 250 MW and PG2 = 0 MW PG1 = 150 MW and PG2 = 100 MW PG1 = 0 MW and PG2 = 250 MW ANSWER DOWNLOAD EXAMIANS APP
Power Systems A generator has reactances of sub transient (X")= 0.5 pu, transient (X') = 0.8 pu and synchronous reactance (X) = 5 pu. The voltages at these reactances are 1.2 V, 1.1 V and 1 V respectively. Find the corresponding sub transient fault current in pu? 1.375 pu 3.975 pu 2.4 pu 0.2 pu 1.375 pu 3.975 pu 2.4 pu 0.2 pu ANSWER DOWNLOAD EXAMIANS APP
Power Systems A transmission line has surge impedance of 400 Ω, operating at Vs = Vr = 400 kV line is compensated with a shunt capacitance of 30%. Find the surge impedance loading with compensation? 400 MW 478 MW 386 MW 456 MW 400 MW 478 MW 386 MW 456 MW ANSWER DOWNLOAD EXAMIANS APP
Power Systems If the breakdown voltage of the insulator is high, the thickness of the insulator is high it does not related to breakdown voltage None of these less high it does not related to breakdown voltage None of these less ANSWER DOWNLOAD EXAMIANS APP
Power Systems If the frequency is increased, then skin effect will any of the above increases remains unaffected decreases any of the above increases remains unaffected decreases ANSWER DOWNLOAD EXAMIANS APP