Why not to use AC Inverter?
230VAC output inverter can do the job.
Voltage may be adjusted for given frequency by programming the parameters.
Boosts should be disabled.
You can find inverters under 1HP for $200US and even lower.
Before following xyzz suggestion you should check if your equipment will accept a PWM-modulated output voltage with 16..20 KHz swicthing frequency and a dv/dt of several kV/µs. Induction motors usually don't complain about that, but if your equipment contains capacitors the might explode quite soon.
Motor-generators have been around for ages that do that very thing. Reasonable clean output. Synchonized to the input, so the output frequency is as stable as your input frequency.
they do produce a frequency inverter with completely clean sine-wave output. No filters involved and efficiency is good. There is one problem, though, they can not deliver more than 11 kW output.
I just suspected that the load is power transformer or another inductive load (otherwise frequency would not be the point).
Of course, more details are necessary for final decision.
California Instruments provides AC power sources.
Generally they have true AC power output stages you can program for a specific voltage and frequency. The inputs can be 110/220V 50/60 Hz
If you are looking for a converter from 220 VAC to power a 3-phase motor at 50 Hz, and you connect with out a converter, maybe don´t hurt you. This will be true for a squirrel-cage motor Design A,B,C, and D (torque and current increase, speed, eficiency and power factor decrease). If the motor is not a squirrel-cage type and have a starter or run capacitor, you need to change the size of the capacitor. Maybe you don´t need a converter. Good luck.
A few years ago we neeeded a temporary source of 50Hz/1Kw
and used a 5kw gas generator, with the speed reduced. We changed a governor spring and tweeked it for 60Hz. It was quite stable, the voltage was close but since the load was light enough there was no serious sag...Just a thought
