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This paper presents the design of an ultraprecise 127-MW/3- \mu \textrm s solid-state modulator with split-core transformer. The modulator consists of a power supply, 12 pulse generator modules with active core reset, and a split-core transformer with six cores. In addition, an $LC$ bouncer could be used to compensate the droop of the pulse. This paper includes the design and analysis of the pulse transformer. A volume minimal transformer is investigated for different load capacitances to investigate the achievable rise time and the parameters which can be used to adjust the damping. In addition, the influence of the pulse transformer on the synchronization of the switches is investigated using an enhanced reluctance model. In addition, an $LC$ bouncer circuit is investigated. A multiobjective optimization is performed which shows the required energy of the bouncer for a certain pulse ripple. The flat-top ripple of the presented modulator can be reduced to 0.2%. Because the bouncer degrades the flat-top stability, the bouncer is not implemented. Measurements of the overall system include short-circuit measurements and flat-top stability measurements. They show that the modulator is short-circuit capable. Furthermore, the flat-top stability is determined to be less than 10 ppm at an output voltage of 360 kV. [ABSTRACT FROM PUBLISHER]

Solid-state modulators based on pulse transformers offer the advantage that, with the turns ratio of the transformer, the primary voltage could ideally be adapted to available switch technology, and a series connection of switches could be avoided. To increase the power level, several semiconductor switches must be connected in parallel, and a balancing between the different switches must be guaranteed. Here, the matrix transformer concept, which is based on multiple primary and/or secondary windings, as well as flux adding, offers superior performance with respect to the achievable rise times. However, the influence of the parasitic elements on the voltage and current distribution is quite involved. In this paper, the influence of the parasitic elements of the matrix transformer on the current balancing and on the winding voltages is investigated based on reluctance models. Additionally, the inherent current balancing of the matrix transformer for windings mounted on different cores is explained. Furthermore, the influence of parasitic load/transformer capacitances on the turnoff transient is discussed in detail. [ABSTRACT FROM PUBLISHER]

A design and optimization procedure for high-voltage pulse transformers is presented. The procedure is enhanced by the integration of core loss measurements under pulsed excitation, by electrical peak field calculations and by checking of the isolation distances, which are compared to scaled high-voltage breakdown data. The procedure is applied with specifications of the compact linear collider, and the sensitivity of system parameters such as the number of primary turns, core material, transformer oil, and high-voltage cable length is investigated by comparing their Pareto fronts. With amorphous core material, the highest efficiency is achieved. Replacing mineral oil by natural ester results in an efficiency reduction of 0.5%, and an increase in HV cable length from 1.5 to 5 m reduces the efficiency by 0.6%. Finally, the optimized transformer’s pulse shape is investigated over the entire load range. [ABSTRACT FROM PUBLISHER]