Driving Principle of a Motor (2)

When voltage is applied, a motor rotates in the forward/reverse direction according to the polarity of the voltage. The rotation speed changes in proportion to the voltage.

・Brushed DC motor
It consists of a stator of permanent magnet, a rotor with coil, a brush, and a commutator.
By rotating the commutator, the current is sequentially applied to the coil. When the direction of the magnetic force of the rotor changes, the propulsive force is generated and then the rotor is rotated.

・Brushless motor
Inverter circuit changes the direction of the magnetic force by switching the direction of the current flowing in the coil.
By changing the direction of the magnetic force of the stator, the propulsive force is generated and then the rotor is rotated.