Optimization of azimuthal transmission lines for magnetically insulated induction voltage adders driven by single or double pulses

As a key component of induction cells in magnetically insulated induction voltage adders (MIVA), azimuthal transmission line plays an important role in symmetrizing the current flows around cell bores, and greatly affects output parameters of cells. Hence, we analyzed the physical principles of designing azimuthal lines for MIVA cells, including symmetrizing current flow, matching impedances, and insulation safety. Some optimized azimuthal line profiles were presented for MIVA cells driven by single or double pulses. By means of three-dimensional electromagnetic models, we simulated the azimuthal distributions of injected currents and output parameters of MIVA cells. The simulation results indicate that the azimuthal uniformity of injected currents for MIVA cells driven by two pulses is better. Consequently, the principal factor for azimuthal lines which should be considered is to match impedances to improve the output response of MIVA cells. The simulation also shows that the non-uniformity for single-pulse-driving cells increases greatly. Thus, adopting an asymmetrical profile of azimuthal lines is helpful for symmetrizing the current flow. After iteratively optimization, the least feed current asymmetry coefficient is 3% for cells driven by double pulses, and 9% for single-pulse-driving cells.