We specialize in wholesale brushless PM motor.Brushless DC electronic rotor position is divided into three types: rotor position sensors are optoelectronic, magneto-sensitive and electromagnetic three types.
The brushless DC motor adopts photoelectric position sensor, the photoelectric sensor is arranged on the stator assembly according to a certain position, the rotor is equipped with a light shield, the light source is a light-emitting diode or a small bulb.When the rotor rotates, due to the role of the shade plate, the photosensitive components on the stator will intermittently send out pulse signals at a certain frequency.
Magnetically sensitive position sensor is a semiconductor sensitive element whose certain points are stated to change with the surrounding magnetic field according to a certain rule. Its basic principle is Hall effect and magnetoresistance effect.The main working principle of magnetic sensitive elements is the magnetic effect of current, mainly Hall effect.Brushless DC motor with magnetosensitive position sensor, the magnetosensitive sensor parts (such as Hall components, magnetosensitive diodes, magnetosensitive triodes, magnetosensitive resistors or special purpose integrated circuits) loaded on the stator assembly, used to detect the permanent magnet, rotor rotation produced by the magnetic field changes.
Brushless DC motor using electromagnetic position sensor is installed on the stator component electromagnetic sensor components, when the permanent magnet rotor position changes, the electromagnetic effect will make the electromagnetic sensor long high frequency modulation signal (its amplitude changes with the rotor position).
In recent years, there is no position sensor brushless DC motor, magnetic motor using stator winding back electromotive force as the position signal of the rotor magnet, the signal detected, processed by digital circuit, sent to the logic switch circuit to control the brushless DC motor commutation.Because it eliminates the position sensor and makes the structure of brushless motor more compact, it is widely used.