The National Standardization Administration Committee issued in the announcement: wireless charging system for electric vehicles Part 1: general requirements (GB/T 38775. 1), wireless charging system for electric vehicles Part 2: communication protocol between vehicle charger and charging equipment (GB/T 38775.2), wireless charging system for electric vehicles Part 3: special requirements (GB/T38775.2)
Standard system planning standard 18 regulates technical requirements, performance requirements, functional requirements, safety requirements, communication protocols, test requirements and test methods, interoperability requirements and test methods, construction acceptance, operation and maintenance, etc. Application of wireless charging system for electric vehicles in public and private fields. This time, four national standards have been issued and are being compiled.
Wireless charging is nothing new in today's era.
Especially if you are using your mobile phone, you may have just picked it up from the wireless charging pad. But for electric vehicles, wireless charging technology has been in the stage of "only hearing its voice, not seeing its people". Although many car companies have demonstrated the wireless charging function of real cars in recent years, they have not been installed in production cars, let alone popularized.
Theoretically, the wireless charging technology of electric vehicles can not only greatly improve the user's car experience, but also pave the way for the unmanned last link of the future autonomous driving scene. An important reason for the delay in entering the market is that countries have failed to formulate a unified standard for this technology as soon as possible, resulting in a series of "chain reactions", which are difficult to scale and market. After the relevant standards are determined, the industry can develop rapidly.
Interestingly, in the national standard issued this time, apart from the leaders of China Electricity Council and China Electric Power Enterprise Association, and the participation of two government departments, namely Electric Power Research Institute and China Automobile Research Institute, only one foreign company participated in the formulation of the national standard-Witricity Company. In fact, WiTricity also participated in the formulation of wireless charging standards for electric vehicles in North America (SAE J2954) and Europe (ISO 19363 and IEC 6 1980).
What is the origin of this company? This has to start with the wireless charging technology itself.
Wireless charging, which originated from Michael Faraday's electromagnetic induction, was invented by Nicholas Tesla and was not really put into use until nearly 10 years ago. At present, there are three main ways: electromagnetic induction, electromagnetic vibration and radio waves; However, because radio wave converts electromagnetic waves into electric energy, it is difficult to balance power and safety, so it is rarely used at present, so it is not mentioned here for the time being.
(Nicholas Tesla's vision of global wireless charging)
Electromagnetic induction, simply understood as the principle of transformer, transmits electric energy to the primary coil, so that the secondary coil is coupled and induced to generate current, thus realizing the "wireless" transmission of energy from one end to the other.
(Schematic diagram of mobile phone wireless charger, drawing/real project)
The principle and hardware requirements of this method are relatively simple, and the relevant standards were formulated earlier. For example, the well-known Qi wireless charging standard was formulated by WPC (Wireless Power Alliance). Therefore, this charging technology has achieved scale, its production cost is low, and it has passed the test of the market and is more popular.
The disadvantage is that the transmission distance is too short due to the limitation of technical principle itself. With the increase of distance, the loss of wireless charging will increase and the efficiency will decrease. So that's why when the phone is a little far away from the wireless charging board, it can't be charged.
Electromagnetic vibration mode is simply understood as an "upgraded version" of electromagnetic induction mode. Essentially, electromagnetic vibration technology is used to improve the efficiency of electromagnetic induction transmission under the condition of loose coupling, so as to ensure the efficiency and realize long-distance transmission (the charging distance and charging area are more than 10 times higher than that of electromagnetic induction mode).
(2007 MIT Professor Marin Sorgia? Me? Electromagnetic vibration wireless charging technology demonstrated by the team)
In 2007, MIT professor Marin Soglia? Me? The team wrote a paper demonstrating the wireless charging technology of electromagnetic vibration. Using two 5-turn copper coils as two ends, a 60W light bulb is lit at a distance of two meters, and the efficiency is about 45%. Subsequently, the research team used the name of the project to set up a private company WiTricity, and applied for related patents for this technology.
Compared with electromagnetic induction, the characteristics of electromagnetic vibration are obviously more in line with the requirements of wireless charging of electric vehicles. Therefore, shortly after the announcement of the technology exhibition, WiTricity received olive branches from Audi, BMW, Chrysler, Jaguar, Nissan and Toyota and expressed their willingness to cooperate with them.
However, after receiving financial support, the development of wireless charging technology applied to electric vehicles is not as expected. There are very few real landing models, such as the 530e iPerformance exhibited by BMW 20 18, which can transmit electric energy wirelessly with a power of 3.2kW.
During this period, competitor Qualcomm acquired Halo Wireless Charging Company and vigorously developed electromagnetic vibration wireless charging technology. It is also announced that the 20 18 Mercedes-Benz S550e will be equipped with wireless charging technology. However, after years of development, Qualcomm may think that the consumer electronics market is more important, so in 20 19, it sold the wireless charging department of electric vehicles and all technical patents to WiTricity.
Since then, WiTricity has won a large number of patents for wireless charging of electric vehicles, and with this advantage, it has begun to promote the formulation of relevant standards in various regions.
In fact, many companies focus on wireless charging technology for electric vehicles, but in the end they either become experimental or find that this technology seems to have no prospect after market research, and finally give up and turn to wireless charging technology in the field of consumer electronics. Most of the major car companies that entered the market early in the morning finally retained a tepid attitude.
(The electromagnetic vibration multi-device simultaneous charging technology demonstrated by WattUp Company can charge a certain range of devices without touching the charging power supply. )
Wireless charging seems to only solve the problem of "laziness" on the surface, eliminating the process of picking up the charging gun and inserting it into the charging port; But in fact, the problem solved by wireless charging is not limited to the second time. Through wireless charging, the charging specifications and interfaces can be completely unified. Compared with wired charging layout, it saves space, can solve many safety problems of charging piles, and can provide completely unmanned operation for self-driving travel business.
(charging robot tested by Tesla)
Of course, from the power point of view, the highest prototype product is 22kW, which is much slower than the overcharge of 100kW. But this does not hinder the practical convenience in many scenes, such as putting the vehicle in the parking lot and parking in the garage at home. The effect brought by wireless charging can really make the vehicle charge all the time without worrying about the "charging" problem.
But then again, so many "pioneers" finally gave up, not because they didn't know these advantages, but because it was not so easy to achieve all this relatively perfectly.
In addition to no advantage in charging speed, the safety of wireless charging of electric vehicles has always been one of the important reasons that hinder market acceptance. Although the 6.78MHz frequency band used in electromagnetic vibration technology is about 30 meters in wavelength from the perspective of scientific demonstration, it is harmless to human body, but the demonstration of these problems still needs a lot of experiments and time.
What's more, the lack of standards before led to the inability of the whole industry to achieve scale, which led to the cost of hardware equipment being much more expensive than wired charging. As a result, it is not cost-effective for individual users or public facilities, and it is difficult to advance. In fact, even if China has formulated relevant standards, it will take a long time to gradually improve the whole industry, so as to gradually reduce costs and be truly accepted by the market.
In other words, for the wireless charging technology of electric vehicles, the current situation is very similar to the initial stage of Tesla, and the immaturity of related industries will inevitably mean the difficulty of the initial stage. Coincidentally, wireless charging technology is very similar to the "bump" experience of electric vehicles. Everything is a hundred years old, not a new technology. However, due to the influence of various environmental factors, it has not really developed; But once these technologies are assisted, they will release energy quickly, showing great development potential.
From quantitative change to qualitative change, the "spring" of electric vehicle charging technology may really come.