The following may be a possible source.

http://www.hzfrequencyconverter.com/

As in post 1, my first thought was motor-generator, too. The TemCo link gave a good description of industrial-scale units, 6KW-20MW. However, your scale is much smaller. Maybe this approach: Use a VFD with input from the available source, and output at the desired frequency. This also meet your solid-state preference, and probably available off-the shelf.

You have described a Pulse Width Modulated or square wave output.

If it is a PWM output, then it may be used to drive a servo motor used in the variable speed ventilator. In that case, it more than likely uses AC input and produces DC voltage for the PWM amplifier.

I'd suggest you get an electrical engineer to analyze your equipment.

Obviously the inverter needs to be sine wave (NOT "Modified sine") output.

Use a switch mode type charger, set to constant float (13.5V) if you intend to keep it on standby for testing purposes.

It may b possible to avoid the battery but if you have any start surge on your load then the voltage drop at the input to the inverter may make it shut down on under-voltage. Remember that the load on the DC link cables will be >40A. Size your cables accordingly, and keep them short.

regads

Chas

Possible suppliers of both pieces of equipment, :- Victon Energy, Mastervolt, Xantrex.

www.victronenergy.com

www.mastervolt.com

www.xantrex.com