Choose the correct answer for the following a- Thevenin's theorem used to 1- Show the operation of the circuit as a source. 2- Simplify complicated circuits. 3- Determine the current in certain branch. b- Norton's Theorem used to 1- Show the operation of the circuit as a source. 2- Simplify complicated circuits. 3- Determine the current in certain branch. c- The iron core of transformers used to: 1- Transfer magnetic flux from primary to secondary winding. 2- Reduce hysteresis and eddy current losses. 3- Initiate magnetic flux. d- The speed of an electron in a current carrying conductor is: 1- The speed of light. 2- In many km per second. 3- In many mm per second. e- The speed of electrical energy inside a current carrying conductor 1- The speed of light. 2- In many km per second. 3- In many mm per second. f- The Imaginary power in AC circuit: 1- Causes no real losses. 2- Causes real losses. 3- Causes imaginary losses. g- The real power in AC circuit transfer: 1- From source to load.

Choose the correct answer for the following a- Thevenin's theorem used to 1- Show the operation of the circuit as a source. 2- Simplify complicated circuits. 3- Determine the current in certain branch. b- Norton's Theorem used to 1- Show the operation of the circuit as a source. 2- Simplify complicated circuits. 3- Determine the current in certain branch. c- The iron core of transformers used to: 1- Transfer magnetic flux from primary to secondary winding. 2- Reduce hysteresis and eddy current losses. 3- Initiate magnetic flux. d- The speed of an electron in a current carrying conductor is: 1- The speed of light. 2- In many km per second. 3- In many mm per second. e- The speed of electrical energy inside a current carrying conductor 1- The speed of light. 2- In many km per second. 3- In many mm per second. f- The Imaginary power in AC circuit: 1- Causes no real losses. 2- Causes real losses. 3- Causes imaginary losses. g- The real power in AC circuit transfer: 1- From source to load.

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 3.33P: Consider the three single-phase two-winding transformers shown in Figure 3.37. The high-voltage...

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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).
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