Scholarlink

<p>Transient electromagnetic (TEM) systems typically transmission step pulses to acquire secondary field information from subsurface media. Both the unstable output during the flat-top segment of the step wave and nonlinear errors during the falling edge can affect detection accuracy. To reduce shutdown time and enhance waveform stability, this paper proposes a segmented optimization control strategy. By employing soft-switching circuit operation mode, clamping capacitor, and high-frequency modulation technology, combined with high-frequency modulation of switching devices and closed-loop control method, the current shutdown time is reduced through adjustment of the clamping voltage. This achieves a stable, fluctuation-free waveform during the flat-top segment of the step wave and improves the linear fitting accuracy of the falling edge waveform. The effectiveness of the proposed strategy is validated through the establishment of simulation and experimental platforms and the conduct of relevant comparative analysis. Experimental results demonstrate that the current maximum deviation during the flat-top segment of the step wave, optimized by the proposed strategy, has been reduced to 0.5A. The shutdown time during the falling edge of the step wave has been shortened to 3.5 µs. The linearity <i>γl</i> relative to the ideal curve has been improved to 92.3%. Consequently, the quality of the step wave after optimization has been significantly enhanced, contributing to the improvement of detection accuracy.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

The Technique of Transient Electromagnetic Transmission Based on Non-Ideal Step Wave Segmented Optimization Control Strategy

  • 期刊论文

  • 发表日期：

    2026年6月17日

查看全文
  • Guo-qiang Xue,
  • Xin-hao Zhang,
  • Qi-hui Zhen,
  • Xin Wu,
  • Xu-hong Wang,
  • Quan-hui Guo,
  • Jian Wang,
  • Yu-chun Chang

摘要

Transient electromagnetic (TEM) systems typically transmission step pulses to acquire secondary field information from subsurface media. Both the unstable output during the flat-top segment of the step wave and nonlinear errors during the falling edge can affect detection accuracy. To reduce shutdown time and enhance waveform stability, this paper proposes a segmented optimization control strategy. By employing soft-switching circuit operation mode, clamping capacitor, and high-frequency modulation technology, combined with high-frequency modulation of switching devices and closed-loop control method, the current shutdown time is reduced through adjustment of the clamping voltage. This achieves a stable, fluctuation-free waveform during the flat-top segment of the step wave and improves the linear fitting accuracy of the falling edge waveform. The effectiveness of the proposed strategy is validated through the establishment of simulation and experimental platforms and the conduct of relevant comparative analysis. Experimental results demonstrate that the current maximum deviation during the flat-top segment of the step wave, optimized by the proposed strategy, has been reduced to 0.5A. The shutdown time during the falling edge of the step wave has been shortened to 3.5 µs. The linearity γl relative to the ideal curve has been improved to 92.3%. Consequently, the quality of the step wave after optimization has been significantly enhanced, contributing to the improvement of detection accuracy.