Yes. It can be simple and cheap.
There are kits out there for 30-60 dollars that are egs002 based, with their circuit board supporting 1000-2000w.
That kit at the start of this post will do fine...
Back to this project after the madness of the last month or so.
My EGS002-based inverter (1000W, but basically just the 2KW without half the fets!).
Use the mains for the 380vdc ( 340v) ( it does not care what volts it is really). then simply choose the 60hz option, you can dial up any output voltage you care to use. The egs002 does not see anything unless you tell it. so you have the VFB set so it outputs 110v, and the jumpers set for 60hz
Done.
You would need the kit, and rectifier and looks like the filter caps are there already ( 450v 105c types). Should be perfect for your purposes. Will cover start up too of the induction motor I would reliably expect.
It does.
So having return the original internal transformer to the 110V job, sealed the box back up... connected the new 240V/50Hz to 110V/60Hz "converter", powered up... and the centrifuge is humming like it normally doesn't. Damnit, the motor is running flat out and the tacho says 3300 RPM!
.... but the lid is open and it shouldn't be running at all!
The circuit for the motor is dead simple (scary simple!).
Mains in. Neutral in goes straight to one side of the motor.
Line (Active) in goes to one side of a triac, out the triac straight to the other side of the motor.
Triac has a basic snubber across it, 10nF + 39R in series.
Triac triggered by 220R in series with an opto-diac (MOC3052) between active and gate.
Scary that the interlock isn't actually in the supply line to the motor...
Anyhow, despite the output "looking pretty good" on the CRO (via an isolating transformer), there is obviously enough high-frequency transient component left to trigger the triac (high dv/dt I guess?).
I whacked a 10uF/400V cap in parallel across the inverter output but it made no difference
I didn't want to have to go to the complexity of building a fancy lowpass filter. Do you think increasing the snubber cap is practical/sufficient, or am I going to need to make a proper filter (suggestions of how much inductance I might need? Do you have a preferred filter type for this application?)