Quote:
Originally Posted by cts_casemod
With that in mind, your single phase 213V RMS has a line to line voltage of 230*sqroot(3) = 370V(RMS) when used as part of a 3 phase waveform
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You need a full bridge to get 600v peak to peak from a 300v battery. The single phase examples show that. You cannot swing a leg more than 300vpp with a half bridge.
The purple line above shows 600v peak to peak between 2 half bridges (a full bridge). That is a line to line voltage, i.e. 213v rms (purple here is the difference between the red and blue lines, ignoring cyan for the moment). Thats it, there aint no more that I can see. You are getting the full 600vpp swing line to line (full bridge) with your 300v battery.
176/1.414 ~ 120v rms sources here.
I *think* the diode circuit is telling us the whole story here (sans overmodulation, etc).
If you took a six lead motor and gave each field a full bridge of its own (i.e. pretend it is 3 single phase motors 120 degrees out), you still won't get more than 600v peak to peak per field coil from a 300v battery.
I see lots of agreement here, just not understanding where 415v rms line2line came from with a 300v battery using only switches. It'd be nice if I was wrong, I guess I'll just grab my popcorn
Edit: added some annotations, with 300vdc, there isn't any more room to make a bigger line to line waveform and still have a sinewave.
