Power Systems Objective Questions & Answers – Set 10

When reactance grounding is used in network, the voltage between neutral and ground is

The ground capacitance existing between transmission line and ground is 4µF. Find the inductive reactance of the peterson coil for compensation of arcing grounds?

The method of neutral grounding affects the

When is the ferranti effect on long overhead lines experienced?

Earth fault relay uses the which of the following sequence currents?

Which of the following grounding is not practically preferred for protection of equipments?

Pelton turbine is a ----------- turbine

In which of the following given faults, all the sequence currents are equal?

An unloaded generator with a pre-fault voltage 1 pu has the following sequence impedance: Z₀ = j 0.15 pu, Z₁ = Z₂ = j 0.25 pu The neutral is grounded with a reactance of 0.05 pu. The fault current in pu for single line to ground fault is

For symmetrical network, the neutral current is

Positive, negative and zero sequence impedances of line are 2,2 and 5 pu respectively. Find self and mutual impedances respectively?

Major share of power produced in India is through

Based on the discharge, Kaplan turbine will discharge

A power system network has n nodes, Z₃₃ of its bus impedance matrix is j0.5 pu. The voltage at node 3 is 1.3∠ -10°. If capacitor is having reactance of -j3.5 pu is now added to the network between node 3 and reference node, the current drawn by the capacitor in pu is

The line currents of 3-phase supply are: I_R = 3 + j 5 A I_Y =2 + j 2 A I_B = -2 - j 1 A The zero sequence current will be

Which of the following statement is/are true?Zn

A transmission line has self and mutual impedances are 0.8 and 0 pu respectively. Find the positive, negative and zero sequence impedances respectively?

The positive, negative and zero sequence impedances of a transmission line are 0.5,0.5 and 1.1 pu respectively. The self (Z_s) and mutual (Z_m) impedances of the line will be given by

For variable heads of near about but less than 30 meters, which type of turbine is used in hydro power station?

More efficient plants are used as

Find the value of a⁷²⁹, where "a" is the operator

Which of the following is low specific speed turbine?

The value of inductance used for compensation of arcing grounds is

A fault occurring at the terminals of an unloaded synchronous generator operating at its rated voltage has resulted in the following values of currents and voltages. I_R0 = j 2.37 pu I_R1 = -j 3.05 pu I_R2 = j 0.68 pu V_R0 = V_R1 = V_R2 = 0.237 pu. Which of the following faults has occurred?

If all the sequence voltages at the fault point in a power system are equal, then the fault point is a

In a 3-phase, 5 kV, 5 MVA system, what is the base impedance?

A transmission line has self and mutual impedances of 0.8 pu and 0.2 pu. Find the positive, negative and zero sequence impedances respectively?

Which of the following is low specific speed turbine?

More efficient plants are used as

The zero sequence current of a generator for line to ground fault is j3 pu. Then the current through the neutral during the fault is