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Originally Posted by Rickertsen2
So what you are saying is that you believe the reactance motor is varying with duty cycle? Do any of you know how to compute reactance over time of a square wave through an inductor? Would you break it up into sine waves and alanlyze the first 20 or so? Is there a simpler way? I can't even find the fourier series for anything but a truly square square wave.
BTW this is entirely possible as both tests had motors attached when they were performed. At this point we seem to have many theories and many untested hypotheses. I Think we will get a much clearer picture of what is going on onve someone measures duty cycle output vs. pwm input.
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Take a look at the picture under the "Choosing a frequency based on motor characteristics" section of this website:
http://homepages.which.net/~paul.hil...ntrollers.html
It shows the relationship between the PWM signal and the motor's current. If someone
was to figure out the RMS current of that waveform at different duty cycles, I believe there would be a non-linear relationship between the RMS current and duty cycle.
Some information on inductor transient response is available here:
http://hyperphysics.phy-astr.gsu.edu...ic/indtra.html