Calculate the per-unit synchronous reactance of machines

Assignment Help Electrical Engineering
Reference no: EM13296013

Superconducting synchronous machines are designed withsuperconducting field windings which can support large currentdensities and create large magnetic flux densities. Since typicaloperating magnetic flux densities exceed the saturation fluxdensities of iron, these machines are typically designed withoutiron in the magnetic circuit; as a result, these machines exhibitno saturation effects and have low synchronous reactances.

Consider a two-pole, 60-Hz, 13.8-kV, 10-MVA superconductinggenerator which achieves rated open-circuit armature voltage at a field current of 842-A. It achieves rated armature current into athree-phase terminal short circuit for a field current of226-A.

a) Calculate the per-unit synchronous reactance.

Consider the situation in which this generator is connected to a13.8-kV distribution feeder of negligible impedance and operating at an output power of 8.75-MW at 0.9 power factor lagging.Calculate:

b) the field current in amperes, the reactive-power output in MVA,and the rotor angle for this operating condition.

c) the resultant rotor angle and the reactive-power in MVA if the field current is reduced to 842-A while the shaft-power supplied by the prime mover to the generator remains constant.

Reference no: EM13296013

Questions Cloud

Find out the motor shaft speed of a digital transducer : A digital transducer has 80 cut-outs. It is used tomeasure the speed of a motor shaft. Output signal frequency is800Hz. Find out the motor shaft speed
Execution by responding to a number of user initiated events : Demonstrate what you have learned in these first two chapters of VB by designing a user interface that controls the order of the tabs, set the initial properties of form controls, and then modifies properties during execution by responding to a..
Determine what is the perimeter of the rectangular field : A farmer measures the perimeter of a rectangualr field. The length of each long side of the rectangle is found to be 38.44 m, and thelength of each short side is found to be 19.5 m. What is theperimeter of the field
How much force must be applied to the end being raised : A uniform chain with a mass of 1.38 kg per meter of length is coiled on a table. One end is pulled upward at a constant rate of 0.54 m/s. how much force must be applied to the end being raised
Calculate the per-unit synchronous reactance of machines : Since typical operating magnetic flux densities exceed the saturation flux densities of iron, these machines are typically designed withoutiron in the magnetic circuit; as a result, these machines exhibitno saturation effects and have low synchron..
Design calculations show that the parameters for generator : Design calculations show that the following parameters for a three-phase, cylindrical-rotor synchronous generator: Phase-a self inductance Laa = 4.83mH Armature leakage inductance Lal = 0.33mH
Interview a clo : Interview a CLO (or research the role of a CLO.) Be prepared to compare and contrast how he or she is building value for his or her organization to the guidelines prescribed by Elkeles and Phillips.
Explain how the design should include acircuit schematic : The output should have an adjustable linear output voltagerange of between 0 to 5 V and be capable of supplying a current of150 mA throughout the voltage range. The design should include acircuit schematic and provide complete specification of all..
Begin to figure out how to determine which bjt is off or why : begin to figure out how to determine which BJT is off or why. I tried modeling the BJT's as two diodes: NPN BJTshares anodes and PNP shares cathodes. Doing it this way doesnot provide the correct answers though. How to determine which one is off o..

Reviews

Write a Review

Electrical Engineering Questions & Answers

  Calculate total charge on plates and potential gradient

The capacitance of a capacitor formed by two parallel metal plates each 200 cm2 in area separated by a dielectric 4 mm thick is 0.0004 microfarads. A p.d. of 20,000 V is applied. Calculate (a) the total charge on the plates

  Find the distance x where the force and charge is given

a total charge Q is uniformly distributed around a ring shape conductorwith radius a.a charge q is located at a distance x from the center of the ring ....the force exerted on a charge is given by F=(qQx)/(4πε(x2+a2)3/2)

  Find the value for required q for the first filter

Find the value for required Q for the first filter.

  What is the speed of the plane with constant speed at angle

a plane diving with constant speed at an angle of 53.0 degree with the vertical releases a projectile at an altitude of 730m.the projectile hits the ground 5 second after release(a)what is the speed of the plane

  Develop a state diagram and table for the circuit

Develop a logic circuit whose output is high when the input has had three consecutive ones to the input. Overlapping threes are allowed. (e.g., x=011110110 then the output z=000110000 assuming starting state was 0).

  Calculate capacitance c needed to improve power factor

for a motor rated Vrms=230v P=300w pf=0.75lagging,calculate the capacitance C needed to improve the power factor to unity assuem frequency =50Hz sketch current and voltage phasors.

  Determine the total current in each line of 3-phase motor

Three -phase motor is connected to a three-phase power source that has an abc phase sequence. the first load is a wye-connected, three-phase motor withdrawing a line current of 20A at a 0.8 lagging power factor.

  Determine the rate of heat transfer in the cooling section

Air Enters a cooling section at 97Kpa, 35C and 30 percent relative humidity at a rate of 6m^3/min, where it is cooled until the moisture in the air starts condensing. Determine the temperature of the air at the exit and the rate of heat transfer i..

  What is the total power in the signal power in the dc signal

b)what is the total power in the signal the power in the DC portion of the signal  and the power in the time-varying portion of the signal c) write the equation for and sketch the power spectral desity of the random signal

  What is the probability that a sample of five units selected

A lot of size N= 30 contains three nonconforming units. What is the probability that a sample of five units selected at random contains exactly one nonconforming unit what is the probability that it contains one or more non conformances

  Find the temperature of the hot filament

A certain lightbulb has a tungsten filament with a resistance of 21.9  when at 20.0°C and 145 when hot. Assume the resistivity of tungsten varies linearly with temperature even over the large temperature range involved here.

  Determine the real power dissipated by the factory

When all the heavy machinery is operational, the total electric current flowing into the factory is 5.7 amperes. The phase angle between the voltage and current waveforms is measured to be 4.0 radians. Find the real power dissipated by the factory..

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd