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1.4.1 Tip: Using multiple step-up transformers
The simplest, easiest choice of step-up transformer is as above – a 1:3 transformer, with a 200 V rated
primary, and 600 V rated secondary
However, if a 600V rated transformer is not available, it is also possible to use multiple step-up Transformers,
with the primaries in parallel or series, and all the secondaries in series.
Again, the VA rating of each must be suitable (in both cases, the load will be shared across the transformers) ,
and you will not be able to generate more than the 25 Watts power from the AT56/AT36.
Ideally, you want to
A, drive the primaries from the AT36/56 class D (10-270V) at around 50-150 Volts, so that there is enough
resolution for the unit control to trim he input to accurately give you the desired output
B, have 10% overhead on the output so that the step-up transformers you are using do not saturate – i.e., in
the largest case, having a 660V capability where the max output ever requested would be 600V
C, Ensure the step-up transformers you use are suitable for the frequency you wish to generate.
Consider the two below examples of the two methods.