Briefly talk about wireless charging technology

dwzt

Briefly talk about wireless charging technology [Copy link]

Before 2014, when you needed to charge your mobile phone, computer, or other electrical appliances, you always had to connect a charging cable. With so many charging cables, you often connected them incorrectly, which was very troublesome. Later, the "wireless charging" technology came out. As long as you elegantly put your mobile phone on a small thing like a coaster, you can easily charge it without connecting any cables. How did such a great technology come about? The electronic products to be charged also have a coil inside. When it is close to the charging station, the magnetic field of the charging station will generate an induced current on the coil of the electronic product through electromagnetic induction. The induced current is guided to the battery, completing the wireless charging between the charging station and the electronic product. People may ask, doesn't the magnetic field have to change to have electromagnetic induction? But the distance between the charging station and the object being charged remains unchanged, so why does electromagnetic induction occur? It turns out that the electricity flowing out of the household socket is "alternating current", which means that the direction of the current keeps changing alternately, sometimes flowing in the same direction, sometimes flowing in the opposite direction. Because of this, the magnetic field generated by the coil of the charging station keeps changing direction, not remaining constant, which meets the conditions of electromagnetic induction. Unfortunately, when charging a smartphone or tablet, the charging efficiency will drop significantly as long as it is a little further away from the charging station. Even with the latest technology, the charging distance cannot exceed 5 cm. In fact, most of the mobile devices that can be wirelessly charged at present must be placed completely flat on the charging station to be charged, which is still a little different from the imagined wireless charging that can be charged on the go. In order to increase the distance and efficiency of wireless charging, scientists are trying to use the principle of "magnetic resonance" for wireless charging. Adding some special components such as capacitors and inductors to the circuit, after proper connection, will form a "resonant circuit". Although radio frequency waves are not involved here, it is very convenient to use RF wireless communication technology to control the forward and reverse rotation and start and stop of some motors.

gmchen

It feels a bit anticlimactic. The first part is very detailed, but the latter part only has one sentence about magnetic resonance. The last part about RF communication and resonant energy transmission is completely unrelated.

dwzt

gmchen posted on 2018-9-3 21:31 It feels a bit anticlimactic. The first part is very detailed, but the latter part only has one sentence about magnetic resonance. The last part about RF communication and resonant energy transfer is...

So I just briefly talk about it. . I can't analyze it in such detail myself.

maychang

dwzt posted on 2018-9-4 09:26 So I just briefly talk about it. . I can't analyze it in such detail myself

There is no need to repeat the posts with exactly the same content in the RF/wireless section and the analog electronics section.

shakencity

Although radio frequency waves are not involved here, it is very convenient to use RF wireless communication technology to control the forward and reverse rotation and start and stop of some motors.