When the winding c-d of the single-phase, 50 Hz, two winding transformer is suppliedfrom an AC current source of frequency 50 Hz, the rated voltage of 200 V (rms), 50 Hzis obtained at the open-circuited terminals a-b. The cross sectional area of the core is5000 mm² and the average core length traversed by the mutual flux is 500 mm. Themaximum allowable flux density in the core is Bmax = 1 Wb/m² and the relative permeabilityof the core material is 5000. The leakage impedance of the winding a-b and windingc-d at 50 Hz are (5 + j100 x 0.16) 9 and (11.25 + j100 x 0.36) 2, respectively.Considering the magnetizing characteristics to be linear and neglecting core loss, theself-inductance of the winding a-b in millihenry is(Round off to 1 decimalplace).a.Vab=200 V50 HzbeCd50 HzACcurrentsource

Given data- Rated voltage E=200 V, Area A=5000 mm2, Length l=500 mm, Relative permeability- μr=5000,…

Answered: When the winding c-d of the…

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.9P

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Similar questions

For a short-circuit test on a 2-winding transformer, with one winding shorted, can you apply the rated voltage on the other winding? (a) Yes (b) No
Consider an ideal transformer with N1=3000andN2=1000 turns. Let winding 1 be connected to a source whose voltage is e1(t)=100(1| t |)volts for 1t1ande1(t)=0 for | t |1 second. A2- farad capacitor is connected across winding 2. Sketch e1(t),e2(t),i1(t),andi2(t) versus time t.
In developing per-unit circuits of systems such as the one shown in Figure 3.10. when moving across a transformer, the voltage base is changed in proportion to the transformer voltage ratings. (a) True (b) False
A transformer has primary and secondary turns of 1250 and 125 respectively. It has core cross-sectionof 36 cm2 and its rms flux density is to be limited to 1.4 T (to prevent core saturation). Whatmaximum 50 Hz voltage can be applied on the primary side and the corresponding open-circuitsecondary voltage?The core has a mean length of 150 cm and its relative permeability can be assumed to be 8000. Whatwould be the rms exciting current when the transformer’s primary winding is excited at a voltage ascalculated above? Also calculate the magnetizing susceptance as seen from primary and secondarysides.If the transformer were to be excited at 60 Hz, 1. What should be the maximum primary voltage for thecore flux density limit not to be exceeded? 2. What would be the magnetizing susceptance as seen oneach side in this case?
The core of a transformer operating at 50 Hz has an eddy current loss of 100 W/m3 and the corelaminations have a thickness of 0.50 mm. The core is redesigned so as to operate with the same eddycurrent loss but at a different voltage and at a frequency of 250 Hz. Assuming that at the new voltage themaximum flux density is one-third of its original value and the resistivity of the core remains unaltered,determine the necessary new thickness of the laminations. Clear and detailed solution.
A small single-phase 60 Hz transformer has 10.2 W at no load. The core has a volume of 750 cm3. The maximum flux density is 10,000 G and the hysteresis constant of the core is 0.0005. Using the Steinmetz law on hysteresis loss, find the eddy current loss.
A 3000/200V ,50hz. , single phase transformer has a cross sectional area of 150 cm2 for the core. If number of turns on the low voltage winding is 80, determine number of turns on the high voltage winding and maximum value of flux density in the core.
b) Calculate the transformer core area that is required to limit the core flux density to 1.75T, when using 1000 turns on the primary and the power supply source is 240V at 50HZ. Write your answer in cm?.
A transformer with normal voltage impressed has a flux density of 1.4 Tesla at rated frequency and a core loss comprising of 1500 W eddy current loss and 3200 W hysteresis loss. What do these losses become under when increasing the applied voltage by 12% and decreased to 68% of rated frequency. Your answer
(a) Explain briefly what is fringing effect and leakage flux. (b) A ferromagnetic core is shown in Figure 1. The depth of the core is 10 cm. The other dimensions of the core are as shown in the figure. By assuming the magnetic leakage to be negligible and relative permeability of the core is 800. Calculate the total reluctance and find the value of the current that will produce a flux of 0.01 Wb. With this current, calculate the flux density at the top of the core 20 cm 40 cm 10 cm, 30 cm 500 turns 30 cm 30 cm Figure 1
The hysteresis coefficient of the core material of a power transformer is 110J/ m3. The eddy current coefficient is 132.87J/m3. The volume of the core is 0.005m3, the thickness of the iron is 0.07 m and the maximum flux density is 1.12T. If the supply frequency is 50 Hz: (a) Determine the hysteresis loss (b) Determine the eddy current loss (c) Determine the core loss of this transformer. (d) Explain how the eddy currents are generated. Suggest one method to minimise this loss. (e) Illustrate the hysteresis losses using a fully labelled hysteresis loop.
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