Tap-changing transformers are designed with their taps positioned on__________?
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Answer: C. high voltage winding
Explanation
High-voltage transformer windings carry lower currents compared to low-voltage windings of equivalent power rating. Lower currents allow tap-changer switch contacts to be smaller and more manageable in mechanical design. Furthermore, high-voltage windings typically feature accessible outer layers suitable for tap connection leads. Tap-changers adjust the turns ratio of power transformers to regulate output voltages under varying loads. Placing taps on the high-voltage side minimizes contact wear caused by switching currents during adjustments. Insulation requirements inside large power transformers dictate careful placement of all internal tap leads.
Electrical substation transformers utilize on-load tap-changers to maintain stable grid transmission voltages. Utility engineers specify tap ranges to compensate for seasonal voltage drops across long transmission lines. Proper tap placement ensures efficient power delivery to residential and industrial consumers despite load changes. Primary winding is incorrect because taps are placed on whichever winding handles high voltage, regardless of role. Secondary winding handles higher currents in step-down transformers, making it unsuitable for tap placement. Any of the above is incorrect because tap placement is specifically restricted to the high-voltage winding.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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