The Wendelstein 7-X (W7-X) stellarator in Greifswald, Germany, represents a leading effort in non-tokamak fusion research. This device is designed to achieve steady-state operation, a key advantage over pulsed tokamaks, by employing a complex, optimized magnetic field geometry. Its construction and operation are part of a long-term German national program aimed at demonstrating the viability of the stellarator concept for future fusion power plants. The W7-X utilizes a modular coil system to generate its intricate magnetic cage, a departure from the simpler toroidal field coils found in tokamaks. Source: Energyencyclopedia
Another prominent stellarator is the Large Helical Device (LHD) located at the National Institute for Fusion Science in Toki, Japan. The LHD has been operational since the late 1990s and has achieved significant plasma performance metrics. It utilizes a pair of large, superconducting helical coils to create the confining magnetic field. The LHD has explored various plasma regimes and fuel cycles, contributing valuable data to the understanding of plasma behavior in helical confinement systems. Its long operational history has allowed for extensive experimental campaigns and iterative improvements. Source: Energyencyclopedia
Another prominent stellarator is the Large Helical Device (LHD) located at the National Institute for Fusion Science in Toki, Japan.
The Helically Symmetric Experiment (HSX) at the University of Wisconsin-Madison is a smaller, but scientifically crucial, stellarator. HSX is designed to test the principle of "quasi-helical symmetry," a magnetic field configuration predicted to reduce neoclassical transport, a major loss mechanism in stellarators. By minimizing this transport, HSX aims to achieve higher plasma confinement and potentially higher fusion gain. Its focused research scope allows for detailed investigation of fundamental plasma physics relevant to all stellarator designs. Source: Energyencyclopedia
Beyond these major facilities, numerous other stellarator experiments are contributing to the global fusion research effort. These include devices in China, the United States, and other nations, each exploring different aspects of stellarator physics and engineering. The diversity of these projects, from large-scale devices like W7-X and LHD to specialized research tools like HSX, underscores the ongoing commitment to developing stellarators as a viable alternative or complement to tokamaks for achieving net energy gain from fusion. Continued operation and analysis from these facilities are vital for advancing the field. Source: Energyencyclopedia