Nuclear fusion experiment reactor 'Wendelstein 7-X' achieved world record of high temperature / high density plasma

by Max-Planck-Institut für Plasmaphysik

A helical type nuclear fusion experiment reactor " Wendelstein 7 - X ( Wendelstein 7 - X ) " developed by Max Planck - Plasma Physics Laboratory produces a higher density plasma at a higher temperature and achieves a longer pulse length Attained world record of Terarator type nuclear fusion reactor at point. It is said that we have made a very good start toward the realization of nuclear fusion power generation, the ultimate power generation technology.

Magnetic configuration effects on the Wendelstein 7-X stellarator | Nature Physics
https://www.nature.com/articles/s41567-018-0141-9

Wendelstein 7-X achieves world record | Max-Planck-Institut für Plasmaphysik
http://www.ipp.mpg.de/4413312/04 _ 18

After the first test phase in 2015 and 2016, a protective wall of "graphite tile" was installed on the inner wall of Wendelstein 7-X plasma vessel. With this coating, plasma discharge at a higher temperature for a long time became possible. The inner wall covered with tiles has a twisted structure, which means that protection power is increased by avoiding collision at the end of the plasma ring.

In the initial phase, the pulse length which was up to 6 seconds has been extended to the maximum of 26 seconds at the present time, and it is said that 75 megajoules of thermal energy can be supplied to the plasma. Plasma generation for a long time has been able to supply 18 times higher thermal energy than the initial phase without divertor , and preconditions for achieving high plasma density are being established. About this result, Dr. Thomas S. Pedersen said, "The result of improving protective walls is very positive."

And by the plasma generation at favorable conditions, the ion temperature is 40 million degrees, the ion density is 800 kJ (0.8 x 10 20) per cubic meter, 600 fusion (6 x 10 26) as the fusion product, K · s / m³ achieved world record. According to Dr. Bedelsen, it seems to be a wonderfully high-value level as a result achieved under realistic conditions by a device of the size Wenderstein 7-X.

For Wendelstein 7-X, it was proved that "optimization" measures are effective when evaluation of the experimental data of the initial phase from December 2015 to March 2016 is completed. In the future, more accurate and systematic evaluation will be carried out in experiments under higher heating power and high plasma pressure.