Re: Speed control

[hylands@ibm.net (Jon Hylands)]

On Fri, 14 May 1999 11:43:23 -0500 (CDT), Nathanael Henderson
<jude@pconline.com> wrote:

>     So, the question to Them That Knows Better is:  Is this a good idea, a
> bad idea, or something else?  Is there an inherent flaw in the idea?

PWM (pulse-width-modulation) is definitely the way to do it "right".
Electric cars all use this.

The advantages are that at low speeds, you're still delivering the full
amount of voltage to the motor, just not very often, so the motor doesn't
lose anywhere near as much torque as it would if you were to vary the
voltage directly.

The disadvantage is that a PWM controller costs a lot of money (into the
hundres of dollars).

Check into the EV (electric vehicle) web pages (a good place to start is
http://dir.yahoo.com/Recreation/Automotive/Alternative_Fuel_Vehicles/Electric_Vehicles

Later,
Jon

--------------------------------------------------------------
   Jon Hylands      Jon@huv.com      http://www.huv.com/jon

  Project: Micro Seeker (Micro Autonomous Underwater Vehicle)
           http://www.huv.com