When friends started showing off their iPhone Xs

Little Hertz doesn't care at all.

Is wireless charging weird?

iPhone wireless charging uses the Qi standard, and its principle is very simple, which is the "electromagnetic induction" we learned in high school▼

iPhone X wireless charging principle:

There is a coil in the charging plate, which is connected to AC. On the phone being charged, there is another coil responsible for generating induced current. When AC is connected to the charging plate, the phone also receives an induced current of the same frequency. After the current is generated, the energy can be stored in the battery, and what happens next is the same as wired charging.

However, there is a drawback to wireless charging through electromagnetic induction, which is that it is only suitable for short-distance charging of small-power electrical appliances. Once the distance is far, the induction becomes weaker and the efficiency of wireless charging becomes poor.

So, how do high-power mobile devices achieve wireless charging?

The power that can drive a car is many orders of magnitude greater than that of a mobile phone. The Guangxi Power Grid Electric Power Research Institute of the Southern Power Grid has successfully developed a high-power and efficient wireless power supply device that can realize wireless charging of electric vehicles, not only for fixed-point charging, but also for charging while walking.

The principle of wireless charging of electric vehicles:

An electric energy transmitting device + an electric energy collecting device

One energy emission

Since a car has two states: parked and driving, the energy emission mechanisms are also different.

The principle of electric energy transmission for fixed-point charging

In actual application on site, the yellow circle in the picture below is the transmitter. The car can be charged by driving over and aiming at it. Of course, as long as your deviation is not too exaggerated and does not exceed 15cm, it will not affect the charging efficiency.

The principle of energy emission while charging while walking

The State Grid Corporation of China adopts a permeable multi-level guide rail mode and topology, which is the first of its kind in China and abroad.

The launcher is just below the yellow line

Energy Pickup

In order to obtain electrical energy, the pickup device must be installed on the vehicle.

The pickup coil can pick up electrical energy, and then convert the high-frequency AC power into the electrical energy required by the electric vehicle through resonance compensation and energy conversion device. It can be used directly to drive the car or stored in the on-board battery at the same time.

So, here comes the question

1 How do you know if your car is fully charged?

Charging monitoring screen can monitor the charging status in real time▼

At the power transmitting end, there is also a corresponding control cabinet▼

2 How fast can wireless charging electric cars go?

The experienced driver did not drive fast, but after testing, it was found that it can fully meet the transportation needs within the city.

3 Can I convert my car into a wirelessly powered electric car?

Yes, but the specific modification requires the cooperation of the car manufacturers, and the cost of a single modification is relatively high. In the future, electric vehicle wireless charging technology will be directly integrated into the car design, and then car manufacturers will be able to directly produce wirelessly powered electric vehicles.

Wireless power supply technology has many application scenarios

1Bus routes and stations

Especially for bus routes with dedicated lanes. In this way, our electric buses don't have to drag long wires.

2 Sightseeing bus routes

Scenic area sightseeing bus routes do not require large parking lots for charging

3 Highways and service areas

Long distances are not a problem, and you can charge your car during a short break

4 Traffic light intersection

You can also charge while waiting for the green light at the intersection

Not long ago, the research results of the mobile wireless charging system for electric vehicles, as one of the most representative innovative achievements of the State Grid Corporation of China, participated in the exhibition of achievements of central enterprises in implementing the new development concept, deeply implementing the innovation-driven development strategy, and vigorously promoting the dual innovation work (referred to as the Central Enterprises Innovation Achievement Exhibition) and received high attention. The research results have received attention and technical cooperation opportunities from government departments, rail transit enterprise research institutes and other institutions.

The mobile wireless charging system for electric vehicles developed by the State Grid Corporation of China has achieved wireless power supply and charging for electric vehicles while driving, which can reduce or even eliminate on-board batteries, ushering in a bright era for wireless power supply for electric vehicles. The core achievements have reached the international leading level.

The electric vehicle mobile wireless charging system was developed by a team led by Dr. Zhu Wenji (pictured above, right) of the Guangxi Electric Power Research Institute of the China Southern Power Grid. It is also the first mobile wireless charging lane in China. A total of 8 invention patents have been applied for and 18 utility model patents have been authorized. Thumbs up to Dr. Zhu, who is both beautiful and intelligent!

Source | Microwaves and Electromagnetic Compatibility

Reply " report " to view all semiconductor industry research reports

Highlights of previous issues ( click on the blue words to read directly ) :

Who else? 3 times faster! Rockchip RK3328 ultra-high definition TV box solution is newly upgraded

The first big party for Chinese lithography professionals, full of practical information! There is always one suitable for you

NB-IoT chip shipments exceed 10 million, and the era of large-scale deployment is coming