Abstract:It is difficult to achieve the ideal square pulse current especially with high inductor load, low loop resistance and low input voltage; therefore, time domain airborne electromagnetic systems such as GEOTEM mostly adopt the half sine wave transmitting circuit to realize the large magnetic moment of emission. This paper describes the design of a novel quasi-resonant modified pulse emission circuit. The modified waveform current generated by this special transmitter with the short edge times is somewhat similar to square waveform, the ideal wave form of broad band transient. On such a basis, a set of fix-wing airborne electromagnetic pulse transmitting system has been developed recently, whose pulse current reaches 650 A and peak moment is up to 500 000 Am2.
李军峰, 李文杰, 刘俊杰. 一种新型的组合波航空电磁脉冲发射系统[J]. 物探与化探, 2014, 38(6): 1186-1189,1199.
LI Jun-Feng, LI Wen-Jie, LIU Jun-Jie. A new type of modified wave airborne electromagnetic pulse transmitting system. Geophysical and Geochemical Exploration, 2014, 38(6): 1186-1189,1199.
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