Analysis and synthesis of an inductive storage millisecond pulse forming network

[摘要] ENGLISH ABSTRACT:Millisecond pulse forming networks (PFNs) as applicable to electro-thermal chemical(ETC) loads fall into the <1 MJ energy bracket. The energy requirements of theseloads require specialised power sources involving staged energy conversion. For the<1MJ energy bracket, capacitive storage systems are usually employed. However,these systems exhibit low volume energy density and for volume sensitiveapplications; alternatives need to be considered.Inductive storage supplies form a sub-group of the static supplies that havetheoretically superior volume energy density characteristics.This thesis documents the execution of a project concerned with the volumeoptimisationof an inductive storage supply. The system is composed of a three stageenergy conversion chain. A prime power source (low power) charges an intermediatestorage (IS) which is characterised by its medium power delivery capabilities. Energyis then transferred from the IS to the storage inductor which is characterised by itshigh power delivery capabilities. When sufficiently charged, the energy is thentransferred to the load. Where pulse forming is required, the inductor storage mustnecessarily be modular. Switching elements to control the energy flow are alsorequired.Work performed at Soreq, Israel, is used as the starting point. A topologyvariation of the XRAM topology presented by Soreq, original to this thesis, ispresented and all its functioning modes are analysed. An existing volume model isanalysed and expanded to incorporate heretofore unmodelled yet non-negligibleconsiderations. The volume model generalises the effect of system modularity, subsystemtechnologies and allows for the incorporation of practical construction issuesinto the design process. The aim is to develop a 500 kJ, 80 kA, 20 kV system with avolume not exceeding lm3. This volume must include the IS, storage inductor and fullswitch volume.The optimisation algorithm and system topology developed in this thesis isvalidated through the construction and testing of a 1.2 kA, 2.5 kV 4 module prototype.A potential full ratings system, composed of contemporary devicetechnologies and exhibiting a volume of just over 0.8m3, is proposed.

[发布机构] Stellenbosch University