Preliminary evaluation of current loss mechanism caused by electron emission at current convergence region on pulsed power facilities

In this paper, DPHC's function in PTS facility was preliminarily explored using NEPTUNE3D code. A series of cold-chamber tests were calculated and analyzed, in which only the electron emission on cathode surface was considered without energy deposition and temperature rise. In order to calculate the acceleration, a simplified 3D geometry model was developed and used as an initial parameter. The full-circuit way about PTS facility was simulated in order to acquire voltage curves from vacuum insulator B under different loads, which were used as input driving signals in following PIC simulations. With the help of visualization tools, the distribution of the magnetic field and the clearer positions of magnetic nulls were both acquired and displayed in 2D and 3D schematics. Calculated results and data proved that DPHC behaved efficiently during current transforming and energy convergence. Preliminary research about the process of electron emission and transportation under high voltage curve were explored, and the current loss efficiencies were estimated to be around 0.46%∼0.48% under different driving sources. The simulation results let us understand the DPHC functions in pulsed power systems better. (authors)