I want to know a very basic thing. We know at 3 phase wye connected alternator, line to line 3rd harmonics voltage is zero. That means it will not add up. But around 40-60% 3rd harmonics could be found across neutral to ground. By which 27TN protection is given.
How this amount of 3rd harmonics formed at neutral point? What is the basic mechanism? Please help.
3rd harmonics in power circuits
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