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Power Engineering

Voltage through 3-uF Capacitance

The current through a 3-uF capacitance is shown in the attachment. At t=0, the voltage is v(0)=10v. Sketch the voltage, power, and stored energy to scale vs. time. In the sketch of each one, I need the equations worked out for each plot. (See attached file for full problem description).

Circuit Elements - Power Dissipated

Given the circuit shown in the attachment find: values and power dissipated. (Please see attachment for complete question and diagram. Thanks)

Circuit Analysis

An electric load operates at 240 volts. The load absorbs an average power of 8Kw at a lagging power factor of 0.8. a) Calculate the complex power of the load b) Calculate the impedance of the load

Rankine Cycle - Net Power, Thermal Efficiency and Heat Transfer

Water is the working fluid in a vapor power cycle with reheat, superheat and reheat. Superheated steam enters the first turbine stage at 8 MPa, 480 C and expands to 0.7 MPa. It then is reheated to 480 C before entering the second turbine stage, where it expands to the condenser pressure of 8 KPa. The mass flow rate of steam e

Complex Power and Impedance

Question: An electrical load operates at 240 volts rms. The load absorbs an average power of 8 kW at a lagging power factor of 0.8. a) Calculate the complex power of the load. b) Calculate the impedance of the load. Please view attachment for multiple choice options.

Dissipations of Power in Lightbulbs

An incandescent lightbulb rated at 100 W will dissipate 100 W as heat and light when connected across a 110-V ideal voltage source. If three of these bulbs are connected in series across the same source, determine the power each bulb will dissipate.

Reactive Power Absorbed by a Line

Two balanced, in parallel connected, three-phase loads are fed by a three-phase line with an impedance of (2+j4) Ohm per phase. The first load is delta-connected with an impedance of (60 ? j45) Ohm per phase, and the second load is Y-connected with an impedance of (30 + j40) Ohm per phase. The line is energized at the sending en

Turbine Unit and Mechanical Output Generated

An area of an interconnected 60 hz power system has three turbine generator units rated 100MVA, 200MVA, and 600MVA respectively. Regulation constants are given for each unit, with the load suddenly decreasing by 100MW. With assumptions made and a frequency response of beta = 165 p.u., calculate the MW decrease in mechanical ou

A Three-Phase Overhead Transmission Line

A three-phase overhead transmission line line has a per-phase resistance of 0.15 ohm/km and a per-phase inductance of 1.3263 mH/km. Assume that the shunt capacitance is negligible. The length f the line is 40 kilometers and it operates under 220 kV and 60-Hz. The line is supplying a three-phase load of 381 MVA at 0.8 power facto

Real Power Generated and Total Real Power Losses

Consider the electric power system show {see attachment}. The power-flow solution of this system can be obtained without resorting to iterative techniques. The elements of the bus admittance matrix Ybus have been calculated as attached. If sigma_2 = 16.97 degrees and sigma_3 = 21 degrees, calculate the real power generated a

Power-Flow Solution (Calculate Phase Angle via Real and Reactive Power Equations)

Consider the electric power system shown {see attachment}. The power-flow solution of this system can be obtained without resorting to iterative techniques. The elements of the bus admittance matrix Ybus have been calculated as: {see attachment}. Calculate the phase angle {see attachment} by using the real and reactive power

Electronics (about operational amplifier)

Show how an ideal Operational Amplifier with an open loop gain = A can be used to provide: i) a non-inverting amplifier with gain= +6v/v. ii) an inverting amplifier with gain= -3v/v. iii) an integrator with gain= +3. Explain the purpose of every component in your circuits. Please see attached for full question.

Electrical Energy Conversion: Synchronous Generator

Synchronous Generator A 250 kVA, 280 V, three-phase, four-pole, 60 Hz, synchronous generator with a synchronous reactance of 0.99 ohms per phase is operating at rated conditions and a power factor of 0.832 lagging. The magnetization curve for the generator is shown in Figure 1. a. Sketch a phasor diagram for the generator. b.

Probability of a False Alarm: Noise Power

The fixed threshold of a radar detector was set, assuming a known noise power, to yield P_FA = 10^-6. The actual noise power was 3 dB higher than expected. What will be the actual P_FA?

Power Systems - Nodal Equations, Y Bus Matrix and P&Q

1. {See attachment for diagram and details}. All reactances are on the System's Base. Write the Nodal Equations and the YBus Matrix. 2. {See attachment for diagram and details}. Find P&Q delivered from the generator's terminals to the system.

Power Systems Problem (3-Phase Fault; Matrices; Matrix Inversion)

For a 3-Phase fault at Bus 3, find (see attachment) the post fault bus voltages for each bus, and the currents to all busses. Show your work, including the Y & Z matrices. Explain your method of matrix inversion. **Please see attachment for complete question and diagram.

Electrical Power Systems Problems

See the attached file. Electrical Power Systems Problems 1. A three-phase line serves a 54MW load with a .9 lagging power factor at a line voltage of 138KV. The line constants are: A = D = 1 at 0 degrees B = 85 ohms At 70 degrees C = 950 x 10^4 siemens at 90 degrees Find the line and phase values of voltage and current

Power Electronics: A Single-Phase Bridge Rectifier

[11.13] A single-phase bridge rectifier has a purely resistive load R=10 Ohms, the peak supply voltage Vm=170 V, and the supply frequency f=60 Hz. Determine the average output voltage of the rectifier if the source inductance is negligible. Answers: a) Vd=120.13 V b) Vd=113.32 V c) Vd=150.42 V d) Vd=80.41 V

[17.18] Power electronics

[Power electronics] The measured values of a diode at a temperature of 25 Degrees Celsius are: Vd=1V at Id=50A, Vd=1.5V at Id=600A. Determine (i) the emission coefficient n, and (ii) the leakage current. ============================================== Answers: a. (a) n=6, (b) Is=0.2A b. (i) n=5, (ii) Is=1A c. (i) n=8, (ii)

Ladder Logic Timers

SEE ATTACHMENT: #4 and the Figure Above it. Questions: a.)What type of timer has been programmed? b.)What is the length of the time-delay period? c.)When does the timer start timing? d.)When is the reset? e.)When will rung 3 be true? f.)When will rung 5 be true? g.)When will output PL4 be energized? h.)Assume that

Peak Value of Output Voltage and Voltage Gain of an Amplifier

A power amplifier when driven by a current source of 5mA rms and a source resistance of 8k, delivers 12.5W signal power to an 8 load resistance. Find peak to peak value of output voltage. If the input voltage to the amplifier shows 5 V rms, determine the voltage gain of the amplifier. The given multiple choice answer is verifi

Power Amplifiers and RMS Value Calculations

A power amplifier when driven by a current source of 5mA rms and a source resistance of 8k, delivers 12.5 W signal power to an 8 load resistance. Find rms value of the output voltage. Show how you arrived at the answer. a) Vo rms = 15V or 10V or 20V or 5V

Watts in Cassette Players

A walker's cassette tape player uses 4 AA batteries in series to provide 6V to the player circuit. The four alkaline battery cells store a total of 200 watts-second of energy. The cassette player is drawing a constant 10ma from the battery pack, what is the normal operating power of the cassette? a) 0.06W b) 0.6W c) 6W d)

How long will the cassette tape player operate at normal power?

A walker's cassette tape player uses 4 AA batteries in series to provide 6V to the player circuit. The four alkaline battery cells store a total of 200 watts-second of energy. The cassette player is drawing a constant 10ma from the battery pack. How long will the cassette tape player operate at normal power? a) 8.3 x 10**