A Three-Module Grouped XRAM Topology for Electromagnetic Railgun Drive: Topology Comparison, Parameter Optimization, and Mechanism Verification

Inductive pulsed power remains attractive for demanding electromagnetic acceleration systems because of its high-current capability and rapid discharge capability. Within this class, XRAM is especially appealing because it combines series charging with parallel discharging of storage inductors. Under high-energy conditions, however, the conventional all-parallel XRAM topology suffers from concentrated blocking-voltage stress on the total output switch and limited effectiveness in transferring stored current to the representative railgun load considered in this work. To address these issues, this paper proposes a three-module grouped XRAM topology and examines its output behavior, parameter dependence, and commutation mechanism. Baseline comparison results show that the grouped arrangement establishes the load-driving path earlier and redistributes device stress more favorably. Its advantage is retained when both topologies are individually optimized with respect to the triggering threshold, indicating that the grouped topology offers a more effective route for high-current electromagnetic acceleration drive through earlier commutation establishment and more effective current transfer.