Cheng Xin-bing, Liu Jin-liang, Qian Bao-liang, Zhang Yu, Zhang Hong-bo
College of Photoelectrical Science and Engineering, National University of Defense Technology, Hunan 410073, People's Republic of China.
Rev Sci Instrum. 2009 Nov;80(11):115110. doi: 10.1063/1.3263902.
A high voltage pulse transformer (HVPT) is usually used as a charging device for the pulse forming line (PFL) of intense electron-beam accelerators (IEBAs). Insulation of the HVPT is one of the important factors that restrict the development of the HVPT. Until now, considerable effort has been focused on minimizing high field regions to avoid insulation breakdown between windings. Characteristics of the HVPT have been widely discussed to achieve these goals, but the effects of the PFL and load resistance on HVPT are usually neglected. In this paper, a HVPT is used as a charging device for the PFL of an IEBA and the effect of the change in the load resistance on the HVPT of the IEBA is presented. When the load resistance does not match the wave impedance of the PFL, a high-frequency bipolar oscillating voltage will occur, and the amplitude of the oscillating voltage will increase with the decrease in the load resistance. The load resistance approximates to zero and the amplitude of the oscillating voltage is much higher. This makes it easier for surface flashover along the insulation materials to form and decrease the lifetime of the HVPT.
高压脉冲变压器（HVPT）通常用作强流电子束加速器（IEBA）的脉冲形成线（PFL）的充电装置。HVPT的绝缘是限制其发展的重要因素之一。到目前为止，相当大的努力都集中在最小化高场区域以避免绕组间的绝缘击穿。为实现这些目标，人们广泛讨论了HVPT的特性，但PFL和负载电阻对HVPT的影响通常被忽略。本文中，一个HVPT被用作IEBA的PFL的充电装置，并给出了负载电阻变化对IEBA的HVPT的影响。当负载电阻与PFL的波阻抗不匹配时，会出现高频双极振荡电压，并且振荡电压的幅度会随着负载电阻的减小而增加。负载电阻近似为零且振荡电压的幅度要高得多。这使得沿绝缘材料的表面闪络更容易形成，并缩短了HVPT的寿命。
