Microstep Unipolar Stepper Motor
Today brings about a new problem. As the title suggests am trying to do microstepping of a unipolar permanent magnet stepper motor, more specifically a 6 wire 7.5 degree motor. Anyway, i've been reading the application note AN822A, where they drive a bipolar motor using microstepping. There was only 2 windings to worry about and the waveform that they used kept one constant while the other varied, however I have more than those used in the application note. The application note lays out what percentages of duty cycle I need, which is fine, and from there I am able to get the duty cycles for pwm. I currently though have two waveform drawings, and don't know which one to use to do the program.
For example, looking at Unipolar diagram and at Uniwave, and four colors for the different windings, red, blue, black and orange. The waveform is as follows:
1: during the first step, A is held at 100% while B starts to slowly charge up, much like the application note does
2: here A is now declining while the fully charged up line B is held high.
3: The next coil starts charging up from 0 so it can attract the rotor and so on.....
This is what I have come up with, is my method of doing it right, as with this two of the coils will always be opposite either 0 or 100% and either charging up or winding down.
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