Development of a high-power time-domain induced polarization transmitter based on optimal absorption circuit
QIAN Wen-Sheng1,2,3(), XI Zhen-Zhu1,2,3, ZHOU Sheng3,4(), QI Qing-Xin5, XIAO Chang-An6, WANG Jun6, XUE Wen-Tao5
1. Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, Central South University, Changsha 410083, China 2. Hunan Key Laboratory of Nonferrous Resources and Geological Disaster Exploration, Changsha 410083, China 3. School of Geosciences and Info-physics, Central South University, Changsha 410083, China 4. Geophysical and Geochemical Survey Institute of Hunan Province, Changsha 410014, China 5. Hunan 5D Geosciences Co. Ltd., Changsha 410083, China 6. Kunming Engineering Corporation Limited, Kunming 650031, China
Large-depth induced polarization sounding requires power supply with long wires and high current. This results in the oscillation of the turn-off waveforms, which greatly affect the accuracy of induced polarization (IP) measurement. To address this issue, this study first constructed a simulation model for electromagnetic induction caused by the long wires for high-power IP transmitters and proposed a method to eliminate IP electromagnetic coupling using an RCD absorption circuit. Then, using the optimal absorption circuit algorithm, the parameters of the optimal absorption circuit were calculated. Afterward, the optimal absorption circuit of the high-power 30 kW IP transmitter was designed, and the simulation results indicate that the optimal absorption circuit effectively mitigated the oscillation of turn-off waveforms. Finally, based on the optimal absorption circuit, a high-power IP transmitter prototype was developed. An AB/2 configuration with a large electrode spacing of 1 500 m was deployed in an area of Shanxi Province. The full turn-off waveforms at four measurement points were repeatedly observed under an emission current of 10 A. With a maximum standard deviation of polarizability estimated at 0.02, the accuracy of the transmitter met the requirements of relevant specifications.
Li D Q, Wang G J, Di Q Y, et al. The application of high-power induced polarization in the middle section of eerguna metallogenic belt[J]. Progress in Geophysics, 2007, 22(5):1621-1626.
[3]
Hren A, Korelic J, Milanovic M. RC-RCD clamp circuit for ringing losses reduction in a flyback converter[J]. IEEE Transactions on Circuits and Systems II:Express Briefs, 2006, 53(5):369-373.
Fu G H, Xiong B, Wang Q R. Design of frequency domain electrical prospecting transmitter based on CPLD[J]. Modern Scientific Instruments. 2009(2):15-17.
Peng X, Zhang Y S, Long X Z, et al. Design of DDF20-1 high power time frequency IP transmitter[J]. Equipment for Geotechnical Engineering, 2021, 22(3):24-26,42.
Zhou F D, Tang H Z, Guo X, et al. Current overshoot produce principle and inhibition of transmitter of time domain electromagnetic detection system[J]. Journal of Jilin University:Engineering and Technology Edition, 2013, 43(4):1023-1028.
[9]
Huang C K, Nien H H, Changchien S K, et al. An optimal designed RCD snubber for DC-DC converters[C]// Hanoi: 2008 10th International Conference on Control,Automation,Robotics and Vision. IEEE,2008:2202-2207.
[10]
Liu F, Liu W J, Zha X M, et al. Solid-state circuit breaker snubber design for transient overvoltage suppression at bus fault interruption in low-voltage DC microgrid[J]. IEEE Transactions on Power Electronics, 2017, 32(4):3007-3021.
[11]
Zhou S, Zhao X, Xi Z Z, et al. Optimal design of classic RCD absorption circuit in transient electromagnetic transmitter[J]. Journal of Geophysics and Engineering, 2022, 19(4):739-749.
[12]
Lin S Y, Chen C L. Analysis and design for RCD clamped snubber used in output rectifier of phase-shift full-bridge ZVS converters[J]. IEEE Transactions on Industrial Electronics, 1998, 45(2):358-359.
Chen J, Lin J, Zhang W X, et al. Induced polarization-similar signal source based on ddfs[J]. Geophysical and Geochemical Exploration, 2010, 34(5):600-603,609.
