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Old 02-25-2004, 08:08 AM
Matt Kirsch
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Location: Spencerport, NY
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Default RE: How does a brushless motor work?

A popular myth that I fell victim to myself. Turns out that even though the ESC does switch the polarity back and forth on the various phases of the motor to make it turn, it's still putting out DC voltage. It's similar to AC, but the wave is a "square" type. Unlike AC, where the voltage gradually changes from maximum + to minimum -, producing a "sine" wave, this switched DC changes from full + to full - instantly.

The picture below kind of shows what I mean. This is what you'd see on the screen of an oscilliscope if you compared true AC to what the brushless ESC is doing, sort of, kinda, maybe
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