Cordless future, thanks to WiTricity

Participants at CES 2010, a consumer electronics show in Las Vegas last month, saw the potential of the future with the announcement of a remarkable 32-inch TV by Chinese consumer electronics maker Haier, which works with Massachusetts-based WiTricity Corporation. I got a glimpse. There was no power cord.

Haier’s prototype was powered by electricity converted from a vibrating magnetic field. Boldly demonstrated at an international trade fair in January, wireless transmission of electricity could realize the quest that AC inventor Nikola Tesla began over a century ago.

The electricity transmitted wirelessly was successfully created in 2005 by a team of MIT physicists led by Professor Marin Soratch. The company they founded, WiTricity Corporation, is currently looking for a partner brand supplier who is interested in licensing transmission methods.

WiTricity technology can be broadly described as “magnetic coupling.” This includes two copper coils with matching magnetic resonances. One is connected to a power source (for example, 110 volt AC house current) and is the “sender”. The sender coil converts the current into a non-radiative magnetic field. This magnetic field oscillates at a specific frequency and penetrates the room. To take advantage of the converted energy, this oscillation frequency of the magnetic field must excite the matching coil housed in electrical appliances such as televisions on display at CES in January.

The idea of ​​a matched resonance of the coil resembles 100 wine glasses on a table, each containing a slightly different amount of water, so each vibrates at its own frequency. An opera star that maintains one sound at sufficient time intervals can eventually smash one particular glass that matches the frequency or pitch with sufficient resonance. In other words, the vibration of the magnetic field only affects equipment with matching coils.

Except for establishing a vibrating magnetic field to resonate and excite a particular receiving coil (creating electrical energy in the appliance), the magnetic field generated by the powered transmit coil is very close to its origin. It remains close to. In addition, WiTricity technology has a very weak impact on biological systems. It is well known as a person or pet.

MIT scientists first demonstrated a successful strategy by illuminating a 60-watt light bulb from 7 feet away. Science July 2007. MIT News Professor Soljacic then said he was awakened by a warning beep from a cell phone that had (again) forgotten to plug it in for charging and was prompted to investigate wireless power. He looked at his cell phone and realized how convenient it would be if it could be charged wirelessly on its own.

Wireless transmission of electrical energy is not a new idea. It was first investigated by Nikola Tesla, a talented scientist who developed AC and induction motors over a century ago. Tesla proved the winner of the so-called “current war” against Edison, who was a supporter of direct current for power generation. Finding a way to make wireless transmission of electricity work over a distance longer than the diameter of the coil is at the heart of the problem, and avoiding directional, intense, and potentially harmful electromagnetic radiation is also at the heart of the problem. did. MIT scientists have overcome these ancient problems.

The Haier TV exhibition with WiTricity at Las Vegas CES simply demonstrated the feasibility (or “proof of concept”) of wireless transmission of electricity.Nevertheless, Haier Popular science Received the “Product of the Future” award in recognition of his efforts so far. The company continues to plan commercial production of efficient wireless power appliances and devices as soon as possible.