An Improved Circuit Topology for the Power Supply Based on Air-Core Pulsed Alternators

The air-core pulsed alternator (APA) power system is distinguished by three key characteristics: low impedance, high power density, and high energy storage density. These attributes render it an optimal choice for direct-drive applications in electromagnetic railguns. In order to supply the necessary current to power electromagnetic railgun loads with high kinetic output, pulsed power supply systems typically require the delivery of several mega-amperes (MAs) of drive current. In such cases, the objective is typically achieved through the parallel operation of multiple pulsed power supply systems, which serves to reduce the output current demand on any single module. When multiple pulsed power supply systems are connected in parallel, the equivalent inductance of the entire power supply system at the end of the discharge period is significantly lower than that of the railgun load. This can result in the discharge switch failing to switch off within a single cycle, which may lead to issues such as excessive current stress on the switch and increased thermal losses in the winding. This article introduces two new submodules: a discharge protection module (DPM) and a fast demagnetization module (FDM). This article begins with an explication of the fundamental operating principles of the air-core pulsed generator power system, which is then followed by the development of a performance verification model for a single power module. Then this article proposes an improved circuit topology for the discharge protection and FDMs, with the objective of guaranteeing a stable switch-off of the discharge rectifier module (DM) within the power system. Furthermore, this article considers the reduction of demagnetization module on system performance.