[Moved] Understanding Push-Pull Amplifier output

Dear All thanks in advance for your help,

I am new to R&D and have been given a design of 1.2kW Class B push-pull amplifier. now I understand the working concept of class B but what i am confused with is working of transformer at the out put. I don't understand how it is summing up the two outputs and why even harmonics are in phase and how do they get cancelled when the are in phase to each other.

Other thing that confuses me that DC supply is center tapped to primary of the transformer, so how is current/voltage distributed between two transistor. I know you might be thinking that i am asking you to design for me but trust me i have spent nights on this but still confused...

I shall appreciate your help.

thanks

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Class B Push-pull Transformer Amplifier Circuit

Class B Amplifier Tutorial

If you are designing an B-Class audio amplifier for speaker supply,
usually the output transformer is not needed,
because of this type amplifier output circuit itself is allready low-impedance.

For example..............

Mono power amplifier 1400 W
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my amplifier is going to be used as Plasma exciter so transformer is required

The DC supply doesn't always need to be at a center tap of the transformer, but it can be convenient to do so since the transformer can act as a choke as well as a transformer (though the transformer then has to handle the DC supply current without saturating).

The even harmonics are out of phase, not in phase, which is why they cancel. That is assuming the two sides of the amplifier are identical.

I read somewhere that even harmonics are inphase and they cancel each other out and it was quite confusing to understand that fact. now i understand and please correct me on that if i am wrong, in push- pull amplifier operation the base band signal is split into two path 180 Deg out of phase now for 0 Deg phase shifted wave transistor amplifies 0 to 180 (peak), whereas for 180 Deg phase shifted wave second transistor amplifies 180 to 360 (trough) and each on of these transistor are off when other one is pushing or pulling the supply/wave (crest/trough). At a point where one switches of and other switches on we get a 0V point i.e. virtual ground.

Please correct me if i am wrong, also please clarify advantages of virtual ground and do we really need it?

thanks