Wireless charging technology (English: wireless charging technology; Wireless charging technology) originated from wireless power transmission technology.
Basically, it can be divided into three types.
Electromagnetic induction type
Alternating current with a certain frequency in the primary coil generates a certain current in the secondary coil through electromagnetic induction, thus transferring energy from the transmitting end to the receiving end. At present, the most common charging scheme is electromagnetic induction. In fact, there is not much mystery in the technical realization of electromagnetic induction solution. As early as 65438+February 2005, China BYD Company applied for the patent of non-contact induction charger, which adopted electromagnetic induction technology.
Magnetic field vibration
It consists of an energy transmitter and an energy receiver. When two devices are tuned to the same frequency or vibrate at a specific frequency, they can exchange each other's energy. This is a technology being studied before a project. The research team led by Marin Soljacic, a physics professor at MIT, used this technology to light a 60-watt light bulb two meters away and named it WiTricity. The coil used in this experiment has a diameter of 50cm and cannot be commercialized. If the coil size is reduced, the received power will naturally decrease.
Radio wave type
This is a mature technology, similar to the crystal receiver used in the early days. It is mainly composed of microwave transmitter and microwave receiver. It can capture the energy of radio waves bouncing off the wall and keep a stable DC voltage while adjusting according to the load. This method only needs a transmitter installed on a wall plug and a "mosquito" receiver that can be installed on any low-voltage product.
In terms of power, it can be divided into low-power wireless charging and high-power wireless charging.
Low power wireless charging
Low-power wireless charging often adopts electromagnetic induction, such as Qi method for mobile phone charging, but ZTE's electric vehicle wireless charging adopts induction method.
High power wireless charging
High-power wireless charging often adopts resonance type (most electric vehicles charge in this way). The power supply equipment (charger) transmits energy to the electric equipment, and the electric equipment uses the received energy to charge the battery and provide it for its own operation. Because the charger and the electrical equipment transfer energy by magnetic field, there is no wire connection between them, so both the charger and the electrical equipment can be exposed without conductive contacts.
After explaining what wireless charging is, we should know the advantages and disadvantages and application scope of wireless charging, otherwise, how can we know why it will become a development trend.
It's still small, mobile phone. With the release of flagship machine every year, wireless charging is often one of the criteria to check whether a mobile phone is in flagship machine. The advantage of wireless is that there is no need for data cable when charging, which solves the problem of complicated wires and reduces the harm to the body caused by frequent unplugging of mobile phones.
The shortcomings are also obvious. The wireless charging base will generate a lot of heat and the power consumption is low. On the contrary, it can't replace wired charging at present. But the changes brought by science and technology are often from scratch, from small to large, so as to better change people's lives and serve people. Recently, Xiaomi demonstrated its new charging technology, which supports input power as high as100W. What is the concept of 100 watt? A 4000 mA large-capacity battery can be fully charged in 17 minutes. Therefore, if this technology is put into mass production, the shortcomings will no longer exist. Let's wait and see.
On the whole, with the continuous popularization of new energy vehicles, the problem of travel charging has become more and more important. How to travel more conveniently and solve the anxiety problem of new energy owners, with the continuous increase of cruising range and the continuous popularization of fast charging, has become a problem for more manufacturers to think about. However, what I never expected was that due to the arrival of the 5G era, car wireless charging travel became more and more realistic.
As early as 20 15, Professor Dong-HoCho of Korea Institute of Science and Technology (KAIST) presided over the laying of a long 12 km road from Kamei Railway Station in southern Korea to Rendong District.
Specially modified buses can charge continuously from this road. During the driving process, the equipment at the bottom of the bus obtains energy from the ground through a technology called "shape magnetic field vibration". The cable installed under the road surface can generate electromagnetic field, and a coil in the bus equipment will interact with it to generate electricity. Complete road charging and provide electric endurance for buses.
Unlimited road toll has been recognized by more countries and professionals. Just in February this year, it was officially confirmed that Zhejiang Province would build the first super highway in China. The super expressway to be built is the Hangzhou-Ningbo double-track expressway, which has been approved by sections. As planned.
It is understood that this expressway will be put into trial operation in 20021year. This expressway will be completed before the Asian Games in Hangzhou in 2022.
The first phase effect map of Ningbo section of Hangzhou-Ningbo double-track expressway
Hangzhou-Shaoxing Expressway (via Ningbo, Shaoxing and Hangzhou), also known as Hangzhou-Ningbo double track, has a planned total length of 16 1 km.
Moreover, this expressway will be turned into a "super expressway" that is "intelligent, fast, green and safe".
The high-speed public security inspection law will build a Intelligent Vehicle Infrastructure Cooperative Systems and fully support autonomous driving for a long time. It can also be combined with wireless charging technology to realize charging while driving. Through intelligent system and vehicle control, the speed can be increased by 20%-30% on the basis of the current average speed of 90 km/h.
Wireless charging road seems to be the most desirable charging method for electric vehicles in the future.
At present, wireless charging is quietly changing our lives. With the development of technology and the continuous improvement of equipment, we will enjoy a more efficient life brought by wireless charging. Therefore, wireless charging is bound to be the future development trend.
It is expected that in the near future, wireless charging can realize long-distance wireless charging like Tesla's long-distance wireless transmission of electric energy, and there is no distance limit. This is the perfect wireless charging method.
At present, it is not hot, only high-end mobile phones have wireless charging function, so it is conceivable that the cost is not low. At present, the application in low-end computers is obviously not mature.
Wireless charging technology does not rely on charging wires at all, but uses magnetic field to charge equipment, which is inspired by wireless power transmission technology. Magnetic vibration is used to transfer the charge in the air between the charger and the equipment, so the coil and capacitor form * * * vibration between the charger and the equipment to realize efficient transmission.
Electromagnetic induction wireless charging technology
For the wireless charging technology of this system, the defects are obvious. The magnetic field will decay rapidly with the increase of distance, and the energy will spread to the outside, so the induced current is far less than the input current, so the energy utilization rate is not high. When charging, the mobile phone must also be close to the charging base, otherwise the charging will be slower, and it will not be charged at all if it is far away.
Wireless charging technology in magnetic vibration mode
Based on the principle of magnetic vibration, coils with the same vibration frequency arranged in the magnetic field transfer electric energy to each other. This wireless charging technology is superior to electromagnetic induction wireless charging technology, which not only prolongs the transmission distance, but also does not need complete overlap between coils.
In addition to the above two wireless charging technologies, there are also electric field coupling wireless charging technology and microwave resonance wireless charging technology. Although wireless charging technology has been developed for several years, many problems restrict its universal application.
Wireless charging has opened up a new charging mode for smart phones, getting rid of the shackles of traditional charging data lines. Although it is difficult to shake the position of direct charging in smart phone charging for the time being, I believe that wireless charging will replace direct charging as the mainstream charging method in the future, and continuous technical optimization will definitely bring users a perfect experience.
If wireless charging doesn't catch fire now, it is estimated that it will be difficult to catch fire in the future. The current wireless charging technology is like baking a mobile phone on an induction cooker. Why do you say that? Because the principle is actually the same, but the power is different.
Yesterday, I also saw a sand sculpture netizen put a Samsung mobile phone on the induction cooker for heating, and the Samsung mobile phone turned off the induction cooker immediately after charging.
If you want to satisfy your curiosity, you can also try your precious mobile phone.
This kind of charging technology makes people worry that it will have a bad influence on the human body, so many people would rather charge slowly with a wired charger than use that thing.
Therefore, if the way of wireless charging does not change, it is difficult to increase such users, let alone get angry. The wrath of the little fruit god
Wireless charging technology is a technology that uses magnetic vibration to transmit magnetic field in the air between charger and equipment, and then converts the magnetic field into electric energy to realize wireless transmission of electric energy.
Have you ever heard that lazy people promote scientific and technological progress? Wireless charging is a technological breakthrough, which brings convenience to users.
Nowadays, many electric devices have switched to wireless charging, such as mobile phones, cameras, tablets, watches, drones, electric toothbrushes and even electric cars.
Wireless charging is already a trend, but it will take time to popularize it.
Wireless charging should not become the mainstream, more applications should be in cars and offices, and there is basically a demand for Apple mobile phones. If the Android machine has a 4000 mAh battery, it's basically no problem for one day. When you get on the bus, throw your mobile phone in the car to charge wirelessly, or in the office, throw your mobile phone on it to charge at any time, because these two types of people may have more mobile phones, or often pick it up and put it down. Frequent plugging and unplugging will damage the charging interface, which is more complicated. Android is now charging 45 watts, 10%-50% only takes more than ten minutes, and wireless charging is generally only 10 watts, which is too slow.
Wireless charging is the progress of science and technology. As time goes by, wireless charging is undoubtedly the mainstream. Just like gasoline vehicles and new energy vehicles, it is only a matter of time before new energy vehicles replace gasoline vehicles.
I feel that I can become the mainstream.
Will it come true? If so, will it discharge wirelessly? If it can be applied to the battlefield of war, the consequences are unimaginable.