The cooling fan motor is divided into DC motor and AC motor according to the type of working power supply.
DC motor includes: brushless DC motor and brush DC motor.
AC motor includes: single motor, three-phase motor.
Among them, single capacitor motor and cover motor are widely used in cooling fan.
Brush DC motor
The stator consists of two or more permanent pole pieces. The rotor consists of a winding and a mechanical commutator connected to a voltage source by a brush. To attract the opposite polarity of the energized winding and the stator magnet, the rotor rotates until it is aligned with the stator. Once the rotor is aligned with the stator, the brush will cross the commutator contact and energize the next winding, resulting in continuous rotation. The speed of the motor is proportional to the voltage applied to it. Reverse the direction of the motor connection and the steering will change.
BLDC motor
The BLDCM has permanent magnet rotor and wound stator. Moreover, the BLDCM can be divided into two categories: one has an external rotating magnet, the other has an internal rotating magnet. In a brushless DC motor, the position of the induction coil (phase) (for a constant magnetic field) is switched (converted) to the appropriate phase by the induced magnetic field generated by the current. Hall effect sensors are usually used to sense the position of the rotor. In addition, the sensor free method can also be used.
Single phase AC motor
Single phase AC motor is a kind of induction motor, as the name implies, it runs on one phase. In a single-phase induction motor, the single-phase supply voltage is divided into two-phase current, which is used to generate a rotating magnetic field for rotating the rotor. The motor type specifies the method to realize phase separation. These motors work in the same way as three-phase induction motors because they consist of stator windings that produce current in the "squirrel cage rotor.".
Single phase AC induction motor type includes: split phase capacitor type, cover pole type, repulsion type
Capacitor and shaded pole motors are the most common. A capacitor motor consists of capacitors connected between the main and auxiliary windings to provide phase shift and rotational flux between these windings. The shaded pole motor is composed of stator winding and stator pole, which is used to receive the "shaded pole ring". The resultant phase shift between the stator and the stator pole produces a rotational flux in the rotor.
Capacitor motor cooling fan cover level motor cooling fan
Three phase synchronous AC motor
Similar to BLDC motor, the rotor of permanent magnet asynchronous AC motor is composed of permanent magnet. The stator consists of three phase windings which are sinusoidal (opposite to the salient distribution in BLDC motor). When 3 cross current is applied, the stator will produce synchronous rotation flux, which makes the rotor rotate synchronously with it. Because of the sinusoidal excitation of the winding, the resultant torque of the motor is much more stable than that of the BLDC motor.
General Motors
General motors are similar to brush DC motors in that they use rotors and commutators with brushes. However, the stator uses windings rather than permanent magnets. basic
The principle is still the same. The series wound motor has a stator winding in series with the rotor. The shunt wound motor has a stator winding in parallel with the rotor winding. A more common series wound motor is also known as a general purpose motor. Whether it is AC or DC voltage source power supply, general motors can operate normally. Reverse the polarity of stator and rotor, they will cancel each other, so the motor rotates in the same direction regardless of polarity.