Optimized radial-transmission-line impedance transformer for a petawatt-class pulsed-power accelerator

摘要

Three-dimensional fully electromagnetic (EM) models are being used to optimize the design of a petawatt-class pulsepower accelerator.^1,2 In this design, a cylindrical array of linear-transformer-driver (LTD) modules³ feed power into radial-transmission-line impedance transformers followed by a vacuum line and convolute section which delivers the combined current to the load.¹ In the limit of small ratio of pulse width to one-way wave transit time, we have previously demonstrated that transport efficiency is maximized when the impedance profile is exponential but deviates for increasing ratio.⁴ We build on that result here with the construction of a virtual accelerator that includes a 3D EM model of a realistic next-generation design for the accelerator's impedance transformer, and circuit models for the LTD drive circuits, vacuum magnetically insulated transmission lines, and load. Variable timing for each LTD module will enable pulse shaping.