Q.38 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 1.0 p.u. The p.u. reactances of different components in the system are also shown in the figure. The infinite bus voltage magnitude is 1.0 p.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 _________.
Q.39 The open loop transfer function of a unity feedback control system is given by
Q.40 At no load condition, a 3-phase, 50 Hz, lossless power transmission line has sending-end and receiving-end voltages of 400 kV and 420 kV respectively. Assuming the velocity of travelling wave to be the velocity of light, the length of the line, in km, is ____________.
Q.41 The power consumption of an industry is 500 kVA, at 0.8 p.f. lagging. A synchronous motor is added to raise the power factor of the industry to unity. If the power intake of the motor is 100 kW, the p.f. of the motor is _____________
Q.42 The flux linkage (λ) and current (i) relation for an electromagnetic system is ߣ = (√݅)/݃. When i = 2A and ݃ (air-gap length) = 10 cm, the magnitude of mechanical force on the moving part, in N, is ________.
Please report if you find any errors in the questions.
Keep watching the space