Do you know what BLDC brushless DC stand fan is? Have you ever wondered why BLDC brushless DC stand fan can save more power than traditional AC stand fans? In today's news, let's discuss why BLDC brushless DC stand fan can save more power than traditional AC stand fans? What are the scientific principles?
The reason of traditional alternating current fan power consumption
First of all, the traditional AC stand fan uses ordinary brush motor, and the core of work is to rely on the carbon brush friction commutation, so in such a process, the carbon brush and rotor will produce mechanical friction in the work, and according to the physics knowledge of junior high school, we all know that friction will generate extra heat, at this time, part of the mechanical energy is converted to internal energy, and this part of the energy is as long as the traditional AC stand fan is working, so most of the mechanical energy is wasted;
Secondly, when the ordinary brush motor is connected to alternating current, traditional AC stand fan can only always maintain the input full power, and the wind speed of different gears can only be changed by the number of coil turns; So even if the lowest wind speed is used, the electric energy that the traditional AC stand fan is connected to is the same as the electric energy of the high wind speed, only the surplus mechanical energy is converted into heat. So when using the traditional AC stand fan, it will not save more power because of the low wind speed, but a large number of electric energy is turned into heat at low speed, which is wasted;
The reason of power saving of BLDC brushless DC stand fan
According to Joule's law, the work done by sliding friction will convert mechanical energy into internal energy, which is usually lost, also known as useless work. So only by turning this part of useless work into useful work can we fundamentally save electricity.
The BLDC brushless DC stand fan relies on the electronic commutation of the Holzer element of the circuit board. There is no sliding friction in the use process. The electric energy of BLDC brushless DC stand fan can almost be converted into mechanical energy, and there is no extra Joule heat.
When the BLDC brushless DC stand fan is working, the first thing to do is to turn the 220V AC into DC through the rectifier bridge to supply the BLDC brush less motor, and then rely on the drive board to flexibly adjust the DC voltage, so as to change the speed. If the gear needs to be higher, it will be adjusted to high voltage. According to the electric power formula P=UI, the power will be higher; In the same way, if the gear needs to be lower, it will be adjusted to low voltage, and the input power will be smaller at the same time. Compared with the traditional AC stand fan, the advantage of BLDC brushless DC stand fan is that when using the low speed gear, it will not rely on the resistance partial pressure to generate Joule heat, so that excessive power consumption can be achieved, "how much power is consumed by how much electricity", and the input electric energy is efficiently converted into mechanical energy, so as to achieve real energy saving.
According to the Joule's law, the electrified conductor will produce the current thermal effect, and the pure resistance heating formula Q=I2Rt, when the resistance of the conductor is larger, the current is larger, and the heat is more. BLDC brushless DC stand fan has changed the magnetic coil of the traditional AC stand fan and replaced it with permanent magnet. The resistance of the permanent magnet is small, and the heat is less. There is no need to carry more current, which greatly reduces the waste of coil heating.
At present, some BLDC brushless DC stand fans in the market also use copper wires, while NAKKA's brushless DC stand fans use all copper wires. The resistivity of copper is much smaller than that of aluminum. According to R= ρ⋅ L/s, copper and aluminum wires of the same length and cross-sectional area, the resistance of copper is smaller, and the Joule heat generated during work is much smaller. Moreover, after a long time of operation, the motor will not be too hot. In addition to power saving, it is also safe. In addition, the copper conductor conduction is more stable in the process of electrifying, and the current loss in the transmission process is small. Therefore, compared with the traditional AC stand fan, the BLDC brushless DC stand fan is still stable in the environment of voltage fluctuation, and there will be no motor weakness and unstable wind speed.
In addition to the above physical principles, the BLDC brushless DC stand fan also uses electromagnetic induction, the coil is forced in the magnetic field, the BLDC magnetic field is stable, the circuit pulse, the ball bearing, and the rolling friction is far less than the sliding friction.
