2. A 20 kVA, 2500/250 V, 50Hz, single-phase transformer gave the following test result: Open-circuit test: 250V, 1.5A, and 100 watts measured on the low voltage side Short-circuit test: 100V, 8A, and 320 watts measured on the on high voltage side On which side the tests were done? Please show your work and highlight your answers Find the approximate equivalent circuit a) Referred to the high side b) Referred to the low side

2. A 20 kVA, 2500/250 V, 50Hz, single-phase transformer gave the following test result: Open-circuit test: 250V, 1.5A, and 100 watts measured on the low voltage side Short-circuit test: 100V, 8A, and 320 watts measured on the on high voltage side On which side the tests were done? Please show your work and highlight your answers Find the approximate equivalent circuit a) Referred to the high side b) Referred to the low side

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 3.10P: A single-phase step-down transformer is rated 13MVA,66kV/11.5kV. With the 11.5 kV winding...

See similar textbooks

Similar questions

For an ideal transformer, the efficiency is (a) 0 (b) 100 (c) 50
The symbol shown is a(n) a. iron core transformer. b. auto transformer. c. current transformer. d. air core transformer.
Consider the three single-phase two-winding transformers shown in Figure 3.37. The high-voltage windings are connected in Y. (a) For the low-voltage side, connect the windings in , place the polarity marks, and label the terminals a, b, and c in accordance with the American standard. (b) Relabel the terminals a, b, and c such that VAN is 90 out of phase with Va for positive sequence.
All values of a transformer are proportional to its __________________ ___________________.
A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters: Resistance of the 2400-V winding: R1=0.75 Resistance of the 240-V winding: R2=0.0075 Leakage reactance of the 2400-V winding: X1=1.0 Leakage reactance of the 240-V winding: X2=0.01 Exciting admittance on the 240-V side =0.003j0.02S (a) Draw the equivalent circuit referred to the high-voltage side of the transformer. (b) Draw the equivalent circuit referred to the low-voltage side of the transformer. Show the numerical values of impedances on the equivalent circuits.
A single-phase step-down transformer is rated 13MVA,66kV/11.5kV. With the 11.5 kV winding short-circuited, rated current flows when the voltage applied to the primary is 5.5 kV. The power input is read as 100 kW. Determine Req1andXeq1 in ohms referred to the high-voltage winding.
In the circuit in Figure 2, the capacitor connected to the a-b terminals of the transformer anda circuit consisting of resistance is defined as a load circuit. a)Find the average power spent by the load circuit? b) How much of the average power calculated in a) by the resistance in the load circuit and how muchspent by the capacitor? Comment on the results obtained?
A 100/S00 V. 1 KVA, 50 Hz transformer was put through open and short-circuit tests to find its internal parameters. The test conditions and derived parameters are as follows Open circut test: The high voltage side terminals were open. The low voltäge side was connected to 10020ª, 50 Hz supply. The low voltage side current was measured as 50245º MA. Short-circuit test The high voltage side terminals were short-circuited. The low voltage side was connected to a variable voltage supply (50 Hz). A full load current of 102-30° A was achieved when the variable voltage supply was at 820° V. The transformer was then put to operation by connecting a load of 400230° 2 to the high voltage side (secondary) while applying a primary voltage of 10020º V. Calculate the primary current (the current drawn from the power supply).
Example 2-2. The equivalent circuit impedances of a 20-kVA, 8000/240-V, 60-Hz transformer are to be determined. The open-circuit test and the short-circuit test were performed on the primary side of the transformer, and the following data were taken: Open-circuit test (on primary) Short-circuit test (on primary) Voc = 8000 V Vsc = 489 V loc = 0.214 A Isc = 2.5 A Voc = 400 W Ps = 240 W
The equivalent circuit impedances of a 20-kVA, 8000/240-V, 60-Hz transformer are to be determined. The open-circuit test and the short- circuit test were performed on the primary side of the transformer, and the following data were taken: Open-circuit test (on primary) Short-circuit test (on primary) 8000 V V= 489 V I0.214 A 2.5 A P= 400 W P= 240 W Find the impedances of the approximate equivalent circuit referred to the primary side, and sketch the circuit.
Q2/A/ What are the conditions for satisfying parallel operation of single phase transformer? Deduce an expression for the load shared by the two transformers in parallel when the transformers have equal voltage ratio? Prove your answer. B/ A 50 KVA, 2300/230 V, 60 11z transformer has a high voltage winding resistance of 0.650 and a low-voltage winding resistance of 0.0065 2. Laboratory tests showed the following results: Open circuit test: V = = 230 V, I =5.7A, P = 190 W Short circuit test: V-41.5 V, I-21.7 A, P-No wattmeter was used. 18 (2) Compute the value of primary voltage needed to give rated secondary voltage when the transformer is connected as a step-up one and is delivering 50 KVA at a power factor of 0.8 lagging. (b) Compute the efficiency under conditions of part (a).
Three-phase, 50 Hz 34500/10500 T/S connected transformer single-phase visible on the side of the high voltage (primary) windings Equivalent circuit parameters are given below. Each of the low voltage (secondary) windings of this transformer When a 7.5 ohm star connected resistive load is connected and the rated voltage is applied to the high voltage windings Find the transformer efficiency. Total iron losses of three phases will be taken as 85000 W. Primary winding internal resistance (?1) 1,85 ohm Primary winding leak reactance (?1) 1,25 ohm Secondary winding internal resistance (moved to primary) (?2′) 1,82 ohm Secondary winding leakage reactance (primary moved) (?2′) 1,25 ohm