A generator feeds power to an infinite bus through a double circuit transmission line. A three phase fault occurs at the middle point of one of the lines. The infinities the bas voltage is 1 pu, the transient internal voltage of the generator is 1.1 pu and he equivalent transfer admittance during fault is 0.8 pu. The 100 MVA generator has an inertia constant of 5 MJ/MVA and it delivering 10 pu power prior of the fault with rotor power angle of 30°. The system frequency is 50 Hz.The initial accelerating power (in pu) will be ______ .
-
Solution
Consider the following unity-feedback system
Which of the following represents the correct region in α-k plane for the system to be stable?
-
Solution
Transistors Q1 and Q2 are matched transistors with VBE(ON) = 0.7 V. The load RL needs a variable current which can range from 0.3 mA to 4 mA such that Q2 is always inactive region.The value of R1 should lie in the region.
-
Solution
Range of lC= 0.3mA - 4 mA
Transistor Q1 and Q2 are matched transistors with VBE(ON) = 0.7 V
When the circuit in figure 1 is excited, the voltage across RL is 4 V. When the same circuit is in figure 2 is excited, the voltage across RL is 4V. When the circuit in figure 3 is excited, the voltage across RL will be
-
Solution
The circuit in figure 1 is excited, the voltage across RL is 4 V
When the same circuit is in figure 2 is excited, the voltage across RL is 4 V.
Use Reciprocity theorem,it is applicable only for single source network. It states that in a single source,linear bilateral network the ratio of excitation to response remain same when position of the excitation and response are interchanged.
When an AC source of emf e = e0 sin(100 t) is connected across a circuit, the phase difference across the e and I in the circuit is π⁄4. The correct combination of the circuit element is
-
Solution
The nominal quiescent collector current of a transistor is 1.2 mA. If the range of b for this transistor is 80 ≤ β ≤ 120 and if the quiescent collector current changes by +10 percent,the range in value for rπ is
A 4 pole wave wound 1200 rpm DC machine has 46 slots with 16 conductors per slots. The induced voltage in the machine is 410 V instead of 480 V at 1200 rpm. The leakage flux in mWb is _________.
-
Solution
The phase angle of the current ‘I’ with respect to the voltage V1 in the circuit shown in the figure is
-
Solution
A pulse of unit amplitude and width ‘a’ is applied to a series RL circuit as shown in the figure. The current i(t) as ‘t’tends to infinity will be
-
Solution
In the figure shown if, we connect a source of 2 V within ternal resistance of 1 Wat A’A with positive terminal at A’, then current through R is______
-
Solution