Solid-state klystron modulators are typically based on oil-immersed high-voltage (HV) pulse transformers because of their high performance, robustness, simplicity, and straightforward design. However, pulse transformer size is fundamentally linked to application pulse length, pulse power, and pulse rise time. For high-power applications transformer size quickly becomes very problematic when approaching pulse lengths on the order of one millisecond. This article presents a systematic study of the applicability of HV pulse transformers for such long-pulse high-power applications. Both the single-layer and pancake winding techniques are evaluated, keeping reduction of transformer volume as the main design objective. First, design models and efficient optimization procedures are developed. The proposed models are validated through circuit simulation, 3-D finite element analysis, and comparison with a commercial HV long-pulse transformer. Then, the developed optimization procedure is used in studying the evolution of pulse transformer size when pulse length is varied from 500 μs to 5 ms assuming peak pulse power requirements corresponding to that of the European Spallation Source (ESS) klystron modulators (115 kV, 100 A, 14 Hz). Finally, the developed trends are used to derive general analytical equations expressing maximum attainable pulse length as a function of application parameters and system constraints.

中文翻译：

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采用单层扁平绕组技术的大功率长脉冲变压器的可行性评估


固态速调管调制器通常基于油浸式高压 (HV) 脉冲变压器，因为它们具有高性能、稳健性、简单性和直接设计。然而，脉冲变压器尺寸从根本上与应用脉冲长度、脉冲功率和脉冲上升时间相关。对于高功率应用，当脉冲长度接近一毫秒时，变压器尺寸很快就会变得非常成问题。本文对高压脉冲变压器在此类长脉冲高功率应用中的适用性进行了系统研究。对单层和扁平绕组技术进行了评估，将减小变压器体积作为主要设计目标。首先，开发设计模型和有效的优化程序。所提出的模型通过电路仿真、3D 有限元分析以及与商用高压长脉冲变压器的比较进行了验证。然后，假设峰值脉冲功率要求与欧洲散裂源 (ESS) 速调管调制器（115 kV，100 A，14赫兹）。最后，所发展的趋势用于推导一般分析方程，将最大可达到的脉冲长度表示为应用参数和系统约束的函数。