Analytical Experiment of Time Evolution of Deceleration Effect in Traveling Wave Direct Energy Converter Using Dual-Frequency Modulation

Traveling wave direct energy converter (TWDEC) was proposed as an efficient energy recovery device for D-3He fusion power generation. It is designed to convert the kinetic energy of 14.7 MeV protons produced by fusion reaction and is based on the inverse process of a linear accelerator. It consists of a modulator and a decelerator. In modulation process, dual-frequency modulation was proposed to improve bunching. Following to the proposal, deceleration experiment was performed, where the conditions of conventional and proposed methods were in a sequence. The result included other effects such as time variation of modulation effect, thus the effect of dual-frequency modulation to deceleration has not been clarified yet. In this work, the deceleration experiment was performed with conventional and proposed methods independently. In addition, time variation of deceleration effect was observed to exclude the time variation of the modulation effect. As a result, the effect of dual-frequency modulation to deceleration process was observed clearly. Higher efficiency was obtained with dual-frequency modulation.