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Sorry, I don't use Labview and I don't have access to it at work or at home.
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Rats...I presume your team software group has LABVIEW on their laptops. Have one of them download the app and give you a five minute lesson on how to alter the parameters on the dashboard. No LABVIEW experience needed. If you still can't do this...then wrap a while loop around my kernel that Eric posted in a C or vbasic or FORTRAN or whatever program you have and do the simulation yourself. Modify the differential equations to match your mental H bridge (I assume its different than mine) and see if you can duplicate what we see.
You remained silent with respect to my H bridge configuration and expanded on my "AL" model in the ppt revision so I assume it matches you model. I claim that this "AL" model is only valid for the coast configuration...which we have established is only in effect for "0" duty, coast enabled conditions.
Please tell me why my PWM off , single diode configuration is wrong or just accept it so we can proceed.
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We know that the EMF does not approach battery voltage until the motor is at free speed so at 30% duty cycle even with no load, the EMF is much lower than the battery.
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Not so for the 120hz victor.
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I agree the diodes conduct during the immediate discharge voltage spike following turn off, but rapidly falls to EMF
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- The rapid fall off is not all that rapid relative to the pwm period for the JAG.
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However, just to run a simple check calculation for current in the Victor during turn on, the motor current works out to over one hundred amps at 30% duty cycle. Even if I work in some numbers for the series resistance (battery internal resistance 11 mohm, Tdson of all FETs=5.3 mohm, motor resistance 90 mohm and allowing for 10 mohm of wiring losses that comes to 116 mohm) the motor current still works out to 95 amps at 30% for 120Hz and a little under 2 amps for the on period of the Jaguar at 15kHz with the same duty cycle.
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You were heading in the right direction but got off a stop early.... The current is indeed high for the victor and the motor/Hbridge resolve the dilemma the only way they can...by raising Vemf to 10 volts. This lowers the currents to what you see in my picture and allows the average current to equal 2.7 amps. This is why the victor speed is so high at .3 duty. My simulation shows Vemf/12 = .84