2. A single-phase, 50-Hz, core-type transformer's no-load voltage ratio is 1,200/440. If the maximum flux is 0.075 Wb, determine the number of turns in each winding. 3. The low-voltage winding of a 3000/200-V, 50-Hz, a single-phase transformer has 80 turns and is installed on a core with an efficient cross-sectional area of 150 cm2. Make a calculation on: a the high-voltage winding's number of turns b. the value of the maximum flux density in the core 4. When supplied at 230 V, 50 Hz, a transformer's no-load current is 5.0 A at 0.3 power factor. The primary winding has a total of 200 tums. Calculate the (i) maximum value of flux in the core, (ii) core loss, and (ii) magnetizing current. 5. A 1-phase transformer has 500 primary and 1200 secondary turns. The net cross-sectional area of the core is 75 cma. If the primary winding be connected to a 400-V, 50 Hz supply, calculate. (i) the peak value of flux density in the core and (i) voltage induced in the secondary winding.

2. A single-phase, 50-Hz, core-type transformer's no-load voltage ratio is 1,200/440. If the maximum flux is 0.075 Wb, determine the number of turns in each winding. 3. The low-voltage winding of a 3000/200-V, 50-Hz, a single-phase transformer has 80 turns and is installed on a core with an efficient cross-sectional area of 150 cm2. Make a calculation on: a the high-voltage winding's number of turns b. the value of the maximum flux density in the core 4. When supplied at 230 V, 50 Hz, a transformer's no-load current is 5.0 A at 0.3 power factor. The primary winding has a total of 200 tums. Calculate the (i) maximum value of flux in the core, (ii) core loss, and (ii) magnetizing current. 5. A 1-phase transformer has 500 primary and 1200 secondary turns. The net cross-sectional area of the core is 75 cma. If the primary winding be connected to a 400-V, 50 Hz supply, calculate. (i) the peak value of flux density in the core and (i) voltage induced in the secondary winding.

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.
For an ideal 2-winding transformer, the ampere-turns of the primary winding, N1I1 is equal to the ampere-turns of the secondary winding, N2I2 (a) True (b) False
For the transformer in Problem 3.10. The open-circuit test with 11.5 kV applied results in a power input of 65 kW and a current of 30 A. Compute the values for GcandBm in siemens referred to the high-voltage winding. Compute the efficiency of the transformer for a load of 10 MW at 0.8 p.f. lagging at rated voltage.
An ideal transformer with N1=1000andN2=250 is connected with an impedance Z22 across winding 2. If V1=10000VandI1=530 A, determine V2,I2,Z2, and the impedance Z2, which is the value of Z2 referred to the primary side of the transformer.
An ideal transformer has no real or reactive power loss. (a) True (b) False
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For developing per-unit equivalent circuits of single-phase three-winding transformer, a common Sbase is selected for all three windings and voltage bases are selected in proportion to the rated voltage of the windings (a) True (b) False
A single-phase 50-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down transformer at the load end of a 2400-volt feeder whose series impedance is (1.0+j2.0) ohm. The equivalent series impedance of the transformer is (1.0+j2.5) ohms referred to the high-voltage (primary) side. The transformer is delivering rated load at a 0.8 power factor lagging and at a rated secondary voltage. Neglecting the transformer exciting current, determine (a) the voltage at the transformer primary terminals, (b) the voltage at the sending end of the feeder, and (c) the real and reactive power delivered to the sending end of the feeder.
Consider Figure 3.4. For an ideal phase-shifting transformer, the imda nce is unchanged when it is referred from one side to the other. (a) True (b) False