Development of High-Power Density, 4-kV Pulse Transformers for TWTA

Abstract

Pulse transformers suitable for high-frequency and high-voltage operations in a traveling-wave tube amplifier (TWTA) had been designed, fabricated, and tested. Two transformers with different operation frequency of 100 and 80 kHz were designed, fabricated, and tested. The transformer with 100-kHz switching frequency had input and output voltages of 250 Vdc and 4.1 kV, respectively. Operating power was 3.06 kW. Achieved power density of the 100-kHz transformers was 22.26 W/cm 3 . The transformer with 80-kHz switching frequency had input and output voltages of 265 Vdc and 4.1 kV, respectively. Normal operating power of the transformer was 1.67 kW. Achieved power density of the 80-kHz transformer was 12.15 W/cm 3 . Three different winding arrangements for the 80-kHz transformer were tested and it was found that the one with a sandwiched primary between secondary windings had the best performance in electrical characteristics. It was possible to reduce the stray capacitance while maintaining low-leakage inductance with the best arrangement. Therefore, the self-resonant frequency was far separated from the operating frequency, and, thus, the new arrangement minimized the self-resonant current that is generally one of source for transformer temperature rise.Index Terms-High-power density, pulse transformer, travelingwave tube amplifier (TWTA).

Design of a Wound Core Pulse Transformer Using Multiobjective Optimization Method

“…4) Current density of the wires must be less than a desired value (5 A/mm 2 is usually an acceptable value). [2], and the results are compared with the parameters of this transformer. In [2], a high frequency pulse transformer for a traveling-wave tube amplifier (TWTA) has been designed using conventional methods.…”

“…[2], and the results are compared with the parameters of this transformer. In [2], a high frequency pulse transformer for a traveling-wave tube amplifier (TWTA) has been designed using conventional methods. Table I presents the parameters of this transformer.…”

“…There are several works about design of a pulse transformer with different goals and views. In [1] and [2], parasitic elements of the transformer have been considered in the design, and several winding structures have been studied to minimize the pulse rise time in the transformer.…”

“…In [2], also an iterative algorithm has been presented to design the transformer windings. In [3], a conventional pulse transformer for the Next linear collider klystron pulse modulator has been designed.…”

Análise, Projeto e Experimentação de um Conversor CC-CC com Múltiplas Saídas em Alta Tensão para Aplicações em Twta

“…Além disto, a válvula apresenta a característica de carga constante, o que é relevante ao projetar a sua fonte de alimentação. A fonte de alimentação de múltiplas saídas de alta tensão pode ser produzida pelos conversores estáticos CC-CC, contudo são projetos com desafios diferentes dos tradicionais devido à alta tensão, como discutido em [7]- [14]. A presença de um transformador no conversor é indispensável para atender os requisitos de alta tensão.…”