Megawatt-Class Gyrotron Developments for Today’s Plasma Fusion Experiments and Future DEMO at Europe

More than nine billion people will live on Earth by 2050, at least one billion people more than today. As the population grows, so does the world’s energy demand. Nuclear fusion is seen as a possible long-term option for a sustainable, non-carbon emitting global energy supply. In southern France, 35 nations are collaborating together to build ITER, the world's largest nuclear fusion experiment. China, a major driver in fusion technology, is amongst them. Several other publicly funded experiments are already operating or are under construction world-wide. In parallel, a number of privately financed start-ups are emerging around the world. All of those demand for powerful, flexible and efficient plasma heating methods. Electron Cyclotron Resonance Heating (ECRH) is a possible option. It allows for localized plasma heating and stabilization. Gyrotron oscillators (gyrotrons) are the only known sources which provide the necessary microwave power at Megawatt-levels and at the required frequencies ranging from below 100 GHz to above 200 GHz. In this presentation, the status and advances in gyrotron research and development, focusing on the developments at Europe, will be provided. ... mehrIt includes the advances in hollow-cavity gyrotrons for European plasma experiments, coaxial-cavity development for future DEMO, the multi-stage depressed collector concept and advanced frequency control of megawatt-class gyrotrons.