I want to build an AC source to test synchros/resolvers/RVDTs. The target is 400 Hz 30 VRMS at maybe 30 VA, but we might want to simulate aircraft "wild power" and drive LVDTs, so maybe 250 Hz to a few KHz.
I'm thinking of using half of a TPA3251 audio amp and a step-up transformer. Like this maybe:
The transformer DCR is low, so a blocking cap might be prudent to prevent DC current in the primary. I have a cute little 1000 uF 2.5V polymer cap in stock, so I could use a few of those in parallel. The diodes keep the cap from exploding if the h-bridge ever rails.
How does that look? Any advice?
I've heard horror stories about "the devil's staircase" progressive saturation, which I don't really understand. The transformer is a toroid, low resistance and pretty dramatic saturation behavior.