## 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 = 150 MW and PG2 = 100 MW
PG1 = 0 MW and PG2 = 250 MW
PG1 = 250 MW and PG2 = 0 MW

## Power Systems When a pumped storage power plant is operated in conjunction with a steam power plant

the operating cost of the steam plant become optimum
chances of the tripping of the system decrease
All of these
load factor of the steam plant is increased

## Power Systems A transmission line has 200 km operating at frequency of 10 Hz Hz. Find the type of the line

any of the above
long transmission line
medium transmission line
short transmission line

## Power Systems The inductance of single phase two wire line is given by

4×10-7× ln(d/r') H/m
0.4×10-7× ln(r'/d) H/m
0.4×10-7× ln(d/r') H/m
4×10-7× ln(r'/d) H/m

## Power Systems The positive (Z1), negative (Z2) and zero sequence (Z0) impedances of a transmission line follows the relation

Z1 = Z2 = Z0
any of the above
(Z1 = Z2) < Z0
(Z1 = Z2) > Z0

less
either 1 or 2
more
None of these