In complex terrain, semi-airborne transient electromagnetic surveying can effectively solve the detailed exploration problems to replace ground manual operation. This method has the advantages of high efficiency, deep exploration depth, and high signal-to-noise ratio. As the core component of the system, the constant-current transmission converter determines the primary field source of the surveying system. High-accurate and stable-output electromagnetic transmission technology is the key issues of the surveying equipment development. In this paper, the converter circuit topology is designed in detail and a novel model reference adaptive proportional-integral control algorithm is put forward. The rising overshoot of current is eliminated and falling edge is linear. Finally, the 20-kW high-power transmitting instrument has been completed and used for field experiments. A large number of experimental results show that the transmitting instrument can achieve high-power constant-current emission, stable output, and good dynamic performance. And the steady-state accuracy is better than the traditional transmitter. The converter successfully improved the semi-airborne transient electromagnetic system detection capability and achieved satisfactory results in field experiments.

中文翻译：

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半机载瞬变电磁测量恒流传输变换器


在复杂地形中，半机载瞬变电磁测量可以有效解决精细勘探问题，替代地面人工作业。该方法具有效率高、探测深度深、信噪比高等优点。恒流传输变换器作为系统的核心部件，决定了测量系统的主要场源。高精度、稳定输出的电磁传输技术是测绘装备发展的关键问题。本文对变换器电路拓扑进行了详细设计，并提出了一种新颖的模型参考自适应比例积分控制算法。电流上升过冲被消除，下降沿呈线性。最终，20kW大功率发射仪已完成并用于现场实验。大量实验结果表明，该发射仪能够实现大功率恒流发射，输出稳定，动态性能良好。并且稳态精度优于传统变送器。该转换器成功提高了半机载瞬变电磁系统探测能力，并在现场实验中取得了满意的结果。