Actually if you build an equivalent to a killer multi Kilowatt audio amplifier I believe you could actually pull it off without allot of invested parts or time.
Then just use a simple sine wave generator as your input signal source. If built properly I would suspect you could very well be way under the 3% mark.
All you would need is a pair of IC's like this or one of its higher voltage cousins set up as a H bridge with a large current amplifying stage behind them.
Just a theory. I do know there are some op amp IC's out there that can run at around 400 volts now. I just don't know what there part numbers are yet.
Then just use a simple sine wave generator as your input signal source. If built properly I would suspect you could very well be way under the 3% mark.
All you would need is a pair of IC's like this or one of its higher voltage cousins set up as a H bridge with a large current amplifying stage behind them.
Just a theory. I do know there are some op amp IC's out there that can run at around 400 volts now. I just don't know what there part numbers are yet.