Guru
Joined: 11/02/2018
Location: AustraliaPosts: 1910
| Posted: 09:17pm 27 Mar 2024 |
An interesting project. Some years ago I did some repairs on a 2kW inverter generator and it does the sort of thing you describe.
The 3 phase permanent magnet alternator fed a 6 diode bridge rectifier producing about 350VDC. The 230V inverter section used 1000V IGBTs.
Primary coarse voltage regulation was via a servo actuator controlling the engine governor. Fine voltage regulation was the inverter feedback system.
The high voltage rating of the IGBTs was probably to cater for the voltage swings you observe.
To get a better idea of how to go about this perhaps get a few service manuals / circuit diagrams for various inverter generators.
Footnote added 2024-03-28 09:36 by phil99
A point I missed above is the engine governor servo actuator is controlled by feedback from the rectifier output. It tries to maintain 350V, however the engine can't respond very fast so there are significant fluctuations when loads are switched.