What's the difference between DC fans and AC fans?
1. Working principle:
The working principle of DC heat dissipation fan is: through DC voltage and electromagnetic induction, the electric energy is converted into machinery to drive the blade to rotate, relying on the coil and IC to switch continuously, and the induction magnetic ring drives the blade to rotate.
The working principle of AC fan: Driven by AC power supply, the voltage will alternate positively and negatively, completely independent of circuit control, generating magnetic field. The change speed of magnetic pole produced by silicon steel sheet is determined by the frequency of power supply. The higher the frequency, the faster the magnetic field switching speed, the faster the rotational speed theoretically. However, the frequency can not be too fast, too fast will cause start-up difficulties.
2. Structural composition:
The rotor of DC heat dissipation fan includes DC heat dissipation fan blade, which is the source of air flow and fan axis. It is used to support balancing fan blade rotation, rotor magnetic ring, permanent magnet, key of magnetic stage switching speed, magnetic ring outer frame and fixed magnetic ring. In addition, the supporting spring is also included, through which the nodule can be fixed to rotate the whole part and the motor part, to produce the direction of rotation, and to be able to move the key speed of rotation. It has good speed regulation performance and simple control.
The internal structure of AC fan (single-phase) is composed of two coil windings, one is start winding, the two windings are connected in series with each other, thus forming three points, the series point is the public end, the start winding end is the start winding end and the start winding end is the running end. In addition, a start-up capacitor is needed, usually between 12 uf, withstanding voltage is usually 250 v, with two joints. One end is connected to the end of the starting winding, the other end is connected to the end of the running winding, forming a triangle type. The power supply (without distinguishing the zero line of the fire line) is connected to the end of the running winding (that is, to the end of the capacitor), the other is connected to the common end, and the grounding wire is connected to the motor housing.
3. Material characteristics:
Material of DC heat dissipation fan: It is made of alloy material and can be used for more than 50,000 hours continuously. The internal structure of DC has transformer and main control board (including frequency conversion circuit, rectifier filter, amplifier circuit, etc.) which are not affected by voltage fluctuation, so its service life is longer.
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