Thread: Question about encoders to control motor
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Unread 10-04-2013, 10:36
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Re: Question about encoders to control motor
Quote:
Originally Posted by DjScribbles View Post
That's not strictly true. If the motor accepts a PWM signal directly, then in some cases you may control it that way, but the speed controller is what receives your pwm signal, and it adjusts the voltage out in proportion to the PWM duty cycle, the motor never sees the pwm on-off cycles.
The motor controller receives PWM as an input signal, and it outputs a PWM voltage to the motor. That's how it adjusts the output voltage... by Pulse-Width-Modulating the 12-volt battery power.

But there is a sense in which you're right. The input PWM period (for the Jag) is 5ms (200Hz). The output PWM frequency (for the Jag) is 15,000Hz. 15,000Hz is fast enough that the inductance of the motor (for a CIM anyway) smooths out the current so there's very little ripple.


Last edited by Ether : 10-04-2013 at 10:48.