Legally Increasing Motor Performance

[Jon Stratis]

Originally Posted by Jared341

Related question: If one was to put additional permanent magnets on the exterior of the motor in order to increase the strength of the magnetic field experienced by the armature, what would the expected result be?

No change in speed or torque?
Changing speed into torque (or visa versa) without increasing max power?
An increase or decrease of max power?

I think I know the answer, but I'd like to hear other opinions.

We didn't do any real scientific tests to see how motor output changes, but we did try this with a Tetrix motor! Start by hooking up a motor and listening to it. Then add a magnet - you can hear the pitch of the motor change! Moving the magnet around, you can tell that the pitch increases if you're adding to the magnetic field, and decreases if you're subtracting from the field. It's important if trying this to find the "sweet spot". Using a multimeter, we tracked the input current while doing this... using a magnet results in a significant increase in current through the motor, based on our observations. Given the Tetrix motor's enthusiasm for burning out (and their ridiculously high cost), we stopped our experimentation there - no need to encourage them to burn out faster... but it's enough to convince us that you can significantly affect a motor's performance by adding magnets to the casing!