AC Harmonics on a system appearing as DC

Question

I have a theoretical question about harmonics and DC.
Given I have a circuit which has a power supply providing an AC input(230Vrms @ 50Hz), this then goes into a load which, takes this supply rectifies it to DC and performs a DC to DC conversion for a DC load.
If the system (load)imposes some DC onto the AC supply it will be seen as a DC offset for instance 1V DC offset. If I were to measure the DC voltage over the Line and neutral going into my load.
Could this hypothetical DC offset be caused by harmonics in the load say the 2nd,3rd,4th harmonic but, appearing as a DC offset.

Transistor · Accepted Answer

In general, a load which is "symmetrical" with regard to the positive and negative half-cycles of the mains will only generate odd harmonics. If the load is not symmetrical and the current waveforms are different on the positive and negative cycles then you will see even harmonics and you may read a DC current component on the line.

Correct answer by Transistor on September 1, 2021

AC Harmonics on a system appearing as DC

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