Featured Research

from universities, journals, and other organizations

High-voltage vacuum power switch for smart power grids: World's first successful power switch using diamond semiconductor

Date:
January 16, 2013
Source:
National Institute for Materials Science
Summary:
New technology may contribute to a new energy strategy for offshore wind energy, efficient power transmission across the Japanese archipelago, and more.

When the diode is “off” (IG = 0mA), no current passes through the vacuum. However, when a current is passed in the diode, the current passes through the vacuum. The current is started from a plate voltage of substantially zero. The right side of the figure shows the condition when the vacuum switch is “on” as seen from above. When the diode is “on,” visible light is emitted. Because light is emitted by the entire diode, it can be understood that a current is passing uniformly through the interior of the solid. It is also thought that electron emission is not concentrated, but occurs from the entire lighted diode.
Credit: Image courtesy of National Institute for Materials Science

Scientists have developed the world's first successful power switch using a diamond semiconductor. In the future, this technology may contribute to a new energy strategy in Japan through offshore wind energy, efficient power transmission across the Japanese archipelago, and more.

Related Articles


As part of problem solving-oriented basic research sponsored by the Japan Science and Technology Agency (JST), a group consisting of researchers at the National Institute of Advanced Industrial Science and Technology (AIST) and the National Institute for Materials Science (NIMS) succeeded in fabricating a vacuum-based high withstand-voltage power switch utilizing the features of a diamond semiconductor and demonstrating its operation. This achievement was a world's first.

As part of problem solving-oriented basic research sponsored by the Japan Science and Technology Agency (JST), a group headed by Dr. Daisuke Takeuchi, a Senior Research Scientist of the National Institute of Advanced Industrial Science and Technology (AIST) and Dr. Satoshi Koizumi, a Principal Researcher of the National Institute for Materials Science (NIMS), succeeded for the first time in the world in fabricating a vacuum-based high withstand-voltage power switch and demonstrating its operation. This result was achieved by utilizing the features of a diamond semiconductor.

In order to introduce renewable energy in power grids and realize the "smart grid" concept, compact power conversion devices (devices that combine multiple power switches) that make it possible to convert and control voltage, current, and frequency are necessary. However, for the power switches developed to date using silicon and similar materials, an extremely large-scale power conversion device had been necessary to withstand high voltages, and this had a been a problem for practical application. Because the withstand voltage (dielectric voltage) of a vacuum is superior to that of semiconductors, which are solids, the development of an innovative vacuum-based power switch that offers an ultra-high withstand voltage, high efficiency, and compact size has been expected.

In order to use a vacuum in a switch, an electron emission device that passes a current through a vacuum when the switch is "on" is necessary. This research group clarified the fact that electrons can be freely emissioned into vacuum when a diamond surface is covered with hydrogen atoms. Therefore, the group developed a vacuum power switch in which a diamond semiconductor is used as the electron emission source. In verification of switch operation, the group confirmed that the device functions as a power switch at a voltage of 10kV. Based on these experimental results, if a vacuum power switch that can withstand voltages as large as 100kV can be fabricated, high power conversion devices with a size 1/10 that of conventional devices are theoretically possible.

In the future, the use of this technology is expected to contribute to realizing a new energy strategy in Japan through introduction of offshore wind energy in the seas surrounding Japan, efficient power transmission across the Japanese archipelago, and similar efforts.


Story Source:

The above story is based on materials provided by National Institute for Materials Science. Note: Materials may be edited for content and length.


Cite This Page:

National Institute for Materials Science. "High-voltage vacuum power switch for smart power grids: World's first successful power switch using diamond semiconductor." ScienceDaily. ScienceDaily, 16 January 2013. <www.sciencedaily.com/releases/2013/01/130116084807.htm>.
National Institute for Materials Science. (2013, January 16). High-voltage vacuum power switch for smart power grids: World's first successful power switch using diamond semiconductor. ScienceDaily. Retrieved November 23, 2014 from www.sciencedaily.com/releases/2013/01/130116084807.htm
National Institute for Materials Science. "High-voltage vacuum power switch for smart power grids: World's first successful power switch using diamond semiconductor." ScienceDaily. www.sciencedaily.com/releases/2013/01/130116084807.htm (accessed November 23, 2014).

Share This


More From ScienceDaily



More Earth & Climate News

Sunday, November 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Newsy (Nov. 22, 2014) For the first time Monterey Bay Aquarium recorded a video of the elusive, creepy and rarely seen anglerfish. Video provided by Newsy
Powered by NewsLook.com
Raw: Buffalo Residents Digging Out, Helping out

Raw: Buffalo Residents Digging Out, Helping out

AP (Nov. 22, 2014) Hundreds of volunteers joined a 'shovel brigade' in Buffalo, New York on Saturday, as the city was living up to its nickname, "The City of Good Neighbors." Video provided by AP
Powered by NewsLook.com
Toyota's Hydrogen Fuel-Cell Green Car Soon Available in the US

Toyota's Hydrogen Fuel-Cell Green Car Soon Available in the US

AFP (Nov. 21, 2014) Toyota presented its hydrogen fuel-cell compact car called "Mirai" to US consumers at the Los Angeles auto show. The car should go on sale in 2015 for around $60.000. It combines stored hydrogen with oxygen to generate its own power. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
Google Announces Improvements To Balloon-Borne Wi-Fi Project

Google Announces Improvements To Balloon-Borne Wi-Fi Project

Newsy (Nov. 21, 2014) In a blog post, Google said its balloons have traveled 3 million kilometers since the start of Project Loon. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins