PYQs Based test 11: Power Systems

In the balanced 3-phase, 50Hz, the circuit is shown below, the value of inductance (L) is 10mH. The value of the capacitance (C) for which all the line currents are zero, in mF, is ___________.

A two bus power system shown in the figure supplies load of 1.0 + j 0.5 p.u.



The values of V₁ in p.u. and δ₂ respectively are

Two identical unloaded generators are connected in parallel as shown in the figure. Both the generators are having positive, negative and zero sequence impedances of $j0.4p.u.,j0.3p.u.andj0.15p.u.$, respectively. If the pre-fault voltage is $1p.u.$, for a line-to-ground (L-G) fault at the terminals of the generators, the fault current, in p.u., is ___________.

The single line diagram of a balanced power system is shown in the figure. The voltage magnitude at the generator internal bus is constant and $1.0p.u.$ The $p.u.$ reactances of different components in the system are also shown in the figure. The infinite bus voltage magnitude is $1.0p.u.$ A three phase fault occurs at the middle of line 2.

The ratio of the maximum real power that can be transferred during the pre-fault condition to the maximum real power that can be transferred under the faulted condition is _________.

In a 132 kV system, the series inductance up to the point of circuit breaker location is 50 mH. The shunt capacitance at the circuit breaker terminal is 0.05 μF. The critical value of resistance in ohms required to be connected across the circuit breaker contacts which will give no transient oscillation is_______.