Check your open volts each phase, are they the same say for 60 RPM ? (pretty easy to click off that count rather close) Be sure to be ready to short the output to slow /stop the alternator. Touble shoot from there so you are positive what you are working with before rectifying and adding the load. Again, your system may not be "bad" at all but just different from what you were expecting based on other's.
If you have a sound 3 phase alternator outputting 3 seperate phases at approximately the same voltage per phase per rpm then I say learn what you do have and work with it before making any radical changes. There is no right or wrong if it works well for you. Keep us posted so we can all learn besides. Dave B. [ Parent ]