Thread: Failed attempt to explain JAG linearity
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Unread 18-05-2009, 13:59
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Re: Failed attempt to explain JAG linearity
Ok Al,
Its about time you dusted off the excel sheet. I feel that you are not yet comfortable with my explanation so we need a few more rounds. The peak current is instructive but is only valid for Vemf = 0 and tells just a small piece of the story. The reason you had to multiply by 10 for the JAG is because the JAG pulses must accumulate to get to the average current with the big L/R. Until you incorporate the discharge half of the cycle which includes the diode you cannot fully explain the nonlinearity, for it is here that the ratio of L/R to PWM period that makes the difference in the average current. Without the diode, this phenomenon would not occur.