[Editor's Note] The wireless world has developed around communication technology, influencing various industrial sectors such as IoT, smartphones, and connected cars, and promoting innovation. Wireless has also pioneered another field called 'power transmission', and is expanding its scope of application not only to smartphones but also to mobility and satellites. With recent innovations in wireless charging and electromagnetic wave-related regulations, wireless power transmission is expected to become a hot topic starting in 2023. We explored related solutions at a small exhibition where companies and organizations developing wireless power transmission products gathered together.

Recently, an exhibition of wireless power transmission products was held at COEX, hosted by the Korea Electromagnetic Wave Promotion Association and the Wireless Power Transmission Promotion Forum.

On this day, companies such as Byenergy, Hwain PowerX, Eta Electronics, Korea Electrotechnology Research Institute, Warp Solution, Konkuk University, Pohang University of Science and Technology, and Seoul National University participated in the exhibition hall and presented a portfolio of products that applied wireless power transmission technology.
On this day, Byenergy Co., Ltd. exhibited next-generation wireless charging technology for electric vehicles. A wireless charger is a device that supplies electric vehicles with power without contact, supplying 85kHz high-frequency current to a wireless charging pad. A receiving pad is installed on the bottom of the car, and when the wireless charging pad on the floor transmits a frequency, the receiving pad receives the frequency, converts it into electricity, and charges the vehicle.

A Byenergy official said that a semi-direct charging system that would allow electric buses to briefly charge when they stop at a bus stop while in motion is currently in the development stage, and predicted that “wireless charging will expand when wired charging becomes widespread nationwide and about one in two drivers owns an electric vehicle.”

In addition, there is a concern that electromagnetic fields (EMF) may be harmful to the human body, so there is a problem that the driver or passengers must get out of the car to charge. Regarding this, an official cautiously predicted, “If combined with autonomous driving technology in the future, cars will automatically move to garages or parking lots with wireless chargers installed, and drivers will get out of the car and go about their business.”

Eta Electronics showcased a kickboard wireless charging system at the exhibition hall. A 6.78MHz 100W wireless power transfer (WPT) solution was installed on the kickboard. Charging can be done from a distance of about 3 to 4 centimeters (cm), and the technology is expected to be applied so that the transmitter is installed on the kickboard stand and the receiver is installed on the front of the kickboard so that wireless charging can be done when it is installed.

An official said, “We are currently conducting field tests on wireless charging technology to be applied to the shared electric kickboard business through collaboration with smart mobility company Hugo.”

The research institute's technological development achievements also shined. The Korea Electrotechnology Research Institute (KERI) was developing and demonstrating high-power electronic steering long-distance wireless power transmission technology. It uses a 5.8GHz frequency in RF mode and consists of a beamforming array with 96 channels and 1,536 radiating elements.

The ultimate goal of the study is to put it on a satellite, send it into space, and then demonstrate energy transfer from the satellite to the ground or from satellite to satellite, he said. In fact, the Korea Electrotechnology Research Institute succeeded in demonstrating a distance of 50 meters (m) in real-time target tracking, and an official said, “At the current level of implementation, there is some loss, but we have achieved power transfer up to 100 meters.”

High-power long-distance wireless power transmission technology is expected to become a core technology for next-generation space solar power generation. After completing core technology development and ground verification by 2025, space demonstration will be conducted starting in 2026 by loading it onto small satellites. To this end, beam scanning technology required for multiple and mobile platform applications and real-time beam correction technology for ground-to-air power transmission will need to be developed in tandem.

Meanwhile, e4ds news will host an Analog Day on December 9th at the Korea Conference Center in Gangnam Station to share the latest EMI/EMC trends and technology information . On this day, Professor Seung-Young Ahn of KAIST, an expert in wireless power transmission technology, will give a session presentation on the outlook for wireless power transmission technology and EMC countermeasures .