1. List any four types of faults that can occur in power transformers?
2. List any four effects of sustained low power factor on equipment.
3. List any four methods that can be used to improve power factor?
4. List any two economic benefits of power factor correction?
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Diesel Generator A I MVA diesel three-phase generator is rated at
4.16 kV, 60 Hz, and connected as Y its neutral is kept floating. It
is directly tied to three loads, one consuming 50% of its capacity,
and each of the other two consuming 25% of its capacity. A
three-phase to ground fault could occur at any of the loads. Draw a
one-line diagram of this system, then describe what type of faults
could occur in the generator and diesel engine. Explain at least
three types of protection strategies that have to be implemented in
such a system, and show necessary fault current calculations.
Assume that any fault impedance you may need is 9.02 pu, and any
component impedance is 0.4 pu.
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What are the types of hackings?
Please specify each types and explain in details of what it is
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Translate the following real world scenario into a signal. Write mathematically. An IV drip is started on a patient of 1000mL saline over 8 hours. At time zero, a linearly increasing drip rate is started for 2 hours. The drip rate is then held constant for 4 hours. The last two hours the drip rate is linearly decreased to zero. Write an analytical expression of the signal in mL/hour.
This is for a signals and systems class. Some basic functions that could be used are u(t) and the delta function.
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Solve the differential equation using undetermined coefficients
y''+3y'-4y=5tet+8t2-4
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Parabolic trough collector. A set of parabolic mirrors can be used to concentrate the sun's rays to heat a fluid flowing in a pipe positioned at the mirrors' focal points. The heated fluid, such as oil, for example, is transported to a pressurized tank to be used to create steam to generate electricity or power an industrial process. Since the solar energy varies with time of day, time of year, cloudiness, humidity, etc., a control system has to be developed in order to maintain the fluid temperature constant. The temperature is mainly controlled by varying the amount of fluid flow through the pipes, but possibly also with a solar tracking mechanism that tilts the mirrors at appropriate angles.
Assuming fixed mirror angles, draw the functional block diagram of a system to maintain the fluid temperature a constant. The desired and actual fluid temperature difference is fed to a controller followed by an amplifier and signal conditioning circuit that varies the speed of a fluid circulating pump. Label the blocks and links of your diagram, indicating all the inputs to the system, including external disturbances such as solar variations, cloudiness, humidity, etc.
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(a) Describe the principle of operation of
(i) Klystron amplifier
(ii) Travelling wave tube (TWT) amplifier.
(b) A parabolic reflector is used to receive a satellite signal of 4 GHz. If the beamwidth of the device is
2.50
(i) find the diameter of the parabolic reflector.
(ii) calculate the gain of the device assuming that the efficiency factor is 50%
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The unit impulse of a system (which isn't necessarily 2nd order) is shown in the figure. In the figure, A denotes the shaded area. You must show that the percentovershoot of the output in response to a step input (%OS) is a linear function of the shaded area A. Show also that the %OS is dependent only on A and the transferfunction DC gain.
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The unit impulse of a system (which isn't necessarily 2nd order) is shown in the figure. In the figure, A denotes the shaded area. You must show that the percentovershoot of the output in response to a step input (%OS) is a linear function of the shaded area A. Show also that the %OS is dependent only on A and the transferfunction DC gain.
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Consider the network shown in Fig. 12.20. Let us determine the resonant frequency, the voltage across each element at resonance, and the value of the quality factor
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The switch in the network in Fig. E7.17 opens at t=0. Find i(t) for t>0
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Three lightbulbs are connected to a 9-V battery as shown in Fig. 2.56 (a). Calculate:
(a) the total current supplied by the battery,
(b) the current through each bulb,
(c) the resistance of each bulb.
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Use source transformation on the circuit shown in Fig 4.98 to find \( I_x \) .
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who discovered the relationship between magnetism and electricity that serves as the foundation for the theory of electromagnetism?
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