Question

why power factor of semi converter is better than full converter

Answer 1

An a.c. electrical system has a characteristic line voltage or phase voltage.  For example, in your home or office, the phase voltage is 115 volts a.c.; in a factory, the line voltage (as for instance to run a pump motor) is usually 460 volts a.c.; and so on.  Some power is "single-phase," some is "three phase," and the line and phase voltages are usually differ from one another in any case; but your question regards power factors, a matter which does not in and of itself require a discussion of lines, phases and such, so we'll speak no further of those here.

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