The second operation phase of W7-X (OP1.2) showed the potential of exclusively electron cyclotron resonance heating (ECRH)-sustained plasma operations in stellarators. Employing multi-pass ECRH scenario in the second harmonic O-mode (O2-ECRH), stationary densities of up to 1.4 10²⁰m⁻³ could be achieved. This scenario also made stationary divertor detachment possible, which is a reactor-relevant scenario for power and particle exhaust. At high densities and with sufficiently high density gradients for an improved ion confinement, the coupling between the electrons and ions was strong enough to bring the ion temperature to values above 3 keV and to the neoclassical limit for some magnetic configurations, thus enabling to test the W7-X neoclassical optimization. The planned enhancement of the ECRH performance will enable to advance towards reactor-relevant beta values and to investigate their stability and confinement of fast particles, which is a priority goal of W7-X.

W7-X (OP1.2) 的第二个运行阶段显示了仿星器中完全电子回旋共振加热 (ECRH) 持续等离子体运行的潜力。在二次谐波 O 模式 (O2-ECRH) 中采用多通道 ECRH 方案，固定密度高达 1.4 10 ²⁰ m ^-3可以实现。这种情况还使固定式偏滤器分离成为可能，这是与反应堆相关的动力和颗粒排放情况。在高密度和足够高的密度梯度以改善离子限制的情况下，电子和离子之间的耦合足够强，可以使离子温度达到 3 keV 以上的值和某些磁性配置的新古典极限，从而能够测试W7-X 新古典优化。ECRH 性能的计划增强将能够推进与反应堆相关的 beta 值，并研究它们的稳定性和快粒子的约束，这是 W7-X 的优先目标。