Diagnostic systems for power balancing large laser fusion facilities

Multiple powerful lasers are shot from large laser fusion facilities synchronously to heat and compress hydrogen fuel to the point where nuclear fusion reactions take place, with the goal of ignition. When the fusion reactions become self-sustaining and controllable, they will provide new clean energy to human beings. Shot reliability is a performance measure of large, multiple beam, power balanced, repairable laser facilities. A diagnostic system with root-mean-square based control charts is presented for evaluation of power balance capability and reliability of the facilities. In the process, a transform from original data to regular data that follows the approximate normal distribution is given to obtain root-mean-square based power balance capability. Then root-mean-square based total control charts and cause-selecting control charts for power balance capability are obtained. Power balance capability indices for the facilities are defined and power balance reliability is also given. Effects of the increasing number of beam lines on the indices and the reliability are analyzed. Advantages of the intuitive and efficient diagnosis of the system are illustrated by analysis of experimental data, e.g., when and where maintenance activities should be done. The studies of output power balance capability of the facilities are fully considered with the expansion of the scale of the facilities. The research shows that the increasing number of beam lines reduces output power balance reliability of the facilities. Therefore, the construction of the laser facilities with more beam lines needs to enhance the current quality of key components and installation. In addition, with regard to reliability research of large and complex systems, statistical diagnosis is as important as technical diagnosis, besides characterizing efficiency and economy.