The Phase Margin (PM) and the damping ratio ξ are related by
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The transfer function of given bode plot is
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Let X(ω)=\(\frac{2e^{-j\omega }}{1-0.25\: e^{-2j\omega }}\), where X(w) is DTFT of x[n], then x[n] is
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A step-down chopper operates from a DC voltage source Vs and feeds a DC motor armature with a back emf Eb. From oscilloscope traces, it is found that the current increases for time tr, falls to zero over time t1 and remains zero for time t0 ,in every chopping cycle. Then the average DC voltage across the freewheeling diode is
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A generator delivers power of 1.0 pu to an infinite bus through a purely reactive network. The maximum power that could be delivered by the generator is 2.0 pu. A three-phase fault occurs at the terminals of the generator which reduces the generator out put to zero. The fault is cleared after tc second. The original network is then restored. The maximum swing of the rotor angle is found to be δmax= 110 elec degree.Then, the rotor angle in electrical degree as t =tc is
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A 4-pole, 3-phase, 50 Hz synchronous machine has its rotor directly coupled to that of a 3-phase slip-ring induction motor.Stators of both machines are connected to the same 3-phase,50 Hz supply. It is desired to use such an arrangement to generate 150 Hz across the rotor terminals of the induction motor. Determine the number of poles for which the induction machine should be wound.
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In an AC circuit using a thyristor having adV⁄dt rating of 25 V/ms,the source inductance is 0.2 mH. The rms value of supply voltage is 230 V. If the damping factor is 0.65, find the values of Rand C of the Snubber circuit
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Find Thevenin equivalent circuit (parameters) about R1,(Given I = 2A)
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In the circuit shown in figure below Vs= 1 V, Rs= 2 W, Y11 =2, Y22= 2 and Y12= Y21= – 1. The resistance RL for the maximum power to be transferred from the source to RL in 0hm is _________.
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Find the motor speed range if Km= 50 rpm/V, and speed(rpm) =KmVm
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