1. Working principle:

Working principle of DC cooling fan:

The principle of DC fan operation is to obtain DC310V DC voltage after PFC and rectification and filtering from the mains. Magnetic rubber magnets exist on the fan rotor. The circuit board IC senses the N/S poles of the rotor magnetic field by comparing the Hall element/current wave/back-EMF. Accurate position, by controlling the MOS switch state, the energized coil will generate a magnetic field. The magnetic field is derived from the silicon steel sheet and interacts with the rotor's magnetic field. The generated repulsive force drives the fan to rotate, and the commutation signal synchronously induces the rotor's rotating magnetic field before switching to energize The coil current flows so that the fan can continue to run.　

The working principle of AC cooling fan: It is driven by AC power, and the voltage will alternate between positive and negative. It does not rely on circuit control at all to generate a magnetic field. The frequency of the power supply is fixed, and the change speed of the magnetic pole generated by the silicon steel sheet is determined by the power supply frequency. The higher the frequency, the faster the magnetic field switching speed, and the faster the rotation speed in theory. However, the frequency should not be too fast, too fast will cause difficulty in starting.

2. Structure composition:

The rotor of the DC cooling fan includes the fan blades of the DC cooling fan, which are the source of air flow, the fan axis, and are used to support the rotation of the balanced fan blades, the rotor magnetic ring, permanent magnets, and promote the magnetic level switching speed key, the magnetic ring frame, Fixed magnetic ring. In addition, it also includes supporting springs. Through these parts, the whole part and the motor part are fixed to rotate the tuberculosis, and the direction of rotation is produced, and the active and large rotation speed is critical. Its speed regulation performance is good, and the control is simple.

The internal structure of an AC fan (single-phase) is composed of two coil windings, one is the start winding, these two windings are connected in series with each other, thus forming three points, the series point is the common end, and the start winding end is the start end operation The end of the winding is the running end. In addition, a starting capacitor is required. The capacity is usually between 12uf and the withstand voltage is usually 250v. There are two connectors, one end is connected to the end of the starting winding, and the other is connected to the end of the running winding, forming a triangle. The power supply (no need to distinguish the live line and the neutral line) is connected to the end of the running winding (that is, it is also connected to one end of the capacitor), and the other is connected to the common end, and the grounding wire is connected to the motor casing.

The difference between a DC motor and an AC motor is that the branch motor has three windings, which are wound on the rotor. A permanent magnet block is installed on the spindle to surround the rotor. It does not need a starting capacitor, but it needs carbon brushes to change the direction of the DC motor. The method is even simpler, as long as you change the positive and negative poles of the power input, it can be achieved!　　

3. Material characteristics:

The material of the DC cooling fan is made of alloy material, and the life span can be used continuously for more than 50,000 hours. The internal structure of the DC has a transformer and a main control board (including frequency conversion circuit, rectifier filtering, amplifying circuit, etc.) that will not be affected by voltage fluctuations, so its Long service life.

The internal structure of the AC cooling fan is mainly a transformer. Most of the materials used by the AC fan are made of domestic discharge needles, usually tungsten needles or stainless steel materials. If the voltage fluctuates too much, it will affect the service life of the transformer.