In alt.engineering.electrical Don Kelly wrote:

| Yes -you are shorting a part of the winding but the switching is a bit more
| complex than that so that short circuit currents are limited to reasonable
| values. It is a multistep operation with reactor switching. On-load tap
| changers are expensive and are generally limited to applications where this
| is absolutely needed (I have seen one where the tap changer was nearly as
| large as the transformer).

What about multiple parallel transformers, or at least multiple parallel
windings on the same core (on whichever side the tapping is to be done),
where the taps are stepped incrementally on each winding? Instead of a
shorted winding segment, you'd have windings of differing voltage in
parallel as each of the windings change their taps one at a time.

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