Thread: best motor type
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Old 12-08-12, 01:13 PM
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graywolf
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Actually, most of the brushless motors are AC. The controller consists of an inverter and a phase converter. The inverter changes the DC from the battery to AC, then the phase converter converts it (usually) to 3-phase. The throttle control changes the frequency to control the speed. Why do you think the wires from the controller to the motor are called phase wires?

Since the controller takes the same type input as a DC motor the brushless motor looks like a DC motor from that viewpoint.

In fact DC motors produce infinite (mathematical definition of infinite) torque at zero rpm. That means real DC motors move off at start up much more smoothly than the AC ones and need no controller other than a reostat. The AC motors (brushless) however are typically smaller and lighter.

There are always tradeoffs, in engineering you chose the ones that work best for your specific application.
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