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Old 12-09-2014, 12:15 AM   #1404 (permalink)
P-hack
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Quote:
Originally Posted by cts_casemod View Post
But for an inverter what we're looking for the line to line, which is 415V, which of course, was proven.
I did notice the author in one of those papers mixed up rms and peak (I mix this stuff up all the time), and/or maybe 415 is based on peak to peak, which isn't how you do rms unfortunately.

But another reverse engineering an inverter from a rectifier hack, to show you the same switching waveforms you are describing, is adding a capacitor. I prefer the leaving one leg on the rail 1/2 (or 1/3 for 3phase) of the time (rotating unipolar I guess) since it is less switching losses and less opportunity for shoot-through (and it is simple enough with a sine table, and processing power is cheap), but you can have bumpy lines on top and bottom and still get 600v peak to peak output (213v rms, i.e. 220v single phase motor at rated voltage) with a sine wave between the leads.

the green lead goes from 300 to 0 as the red goes from 0 to 300 and cyan shows the result. pink is the bus to ground (or the battery in reverse engineering mode). 150v is 0% duty cycle. 300v is 100% duty cycle for a top leg and for the catacorner bottom leg. same only different for 0v.

Sorry, I don't see where 415vrms is gonna come from with a 300v battery.

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Last edited by P-hack; 12-09-2014 at 03:38 AM..
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