Jack// ani said:
I think you got something wrong, or I didn't expressed it correclty!
Say you have two AC sources of 110V, now if I put them in series they
should add up to give 220V if their instantaneous phases are same(0 or
360) or if they are 180 phase out they should sum up to zero. I think
these two AC sources are just like two phases of 3-phase AC supply
which are 120degree phase apart. And they should give a voltage less
than 220V when summed up.
Any Help...Thanks
Your two single phase 110 sources in series will give 220V or 0 depending on
connection. This is the Edison or 3 wire single phase system in the 220V
case (and something useless in the other case) which is a common North
American configuration. In Europe, where it is not used, it is called a 2
phase system and if one defines an phase system as having n voltages to
neutralThere are two basic forms of a 3 phase connection -star in which
there is a common neutral or delta where there is no neutral. .You mention a
voltage of 110V to neutral so the corresponding voltage between lines is
110*root(3)=190V.
In a star connected 3 phase system the phase and line currents are the same
but line to line voltages are greater than phase to neutral voltages by the
factor of root(3). In a delta the phase and line to line voltages are the
same but the line (external) currents are root(3) times the phase (internal)
currents.
There are advantages and disadvantages to both and advantages for 3 phase
over single phase (2 or 3 wire), particularly in rotating machines and
transformers.