Resear On The Special Power Supply For Electromagnetic Detecting

In electromagnetic detecting, the quality of the transmitting waveform directly influences data quality and data processing. However, in a long period, the undeveloped status in electromagnetic transmitting technology restricts the development of transient electromagnetic applications in China. Focused on the electromagnetic transmitting technology in electromagnetic prospecting field, the thesis studies the electromagnetic detecting transmitting technology, which is supported by National Natural Science Foundation of China (50577071)"research on the superficial transient electromagnetic method based on standard field source".The thesis analyzes the effect on TEM response by transmitting parameters, and cognizes that cutting short the rising time can minish the waveform aberration, and improve the work efficiency. By analyzing several kind of fall-edge effect amending arithmetic, the thesis concludes that the bi-polarity current pulse with high current, short turn-off time, and linear fall-edge is the technical trend of transient electromagnetic transmitting.The thesis comprehensively analyzes the present status, problems and trend of electromagnetic transmitting technology, concludes much shortcomings of many transmitting circuits, such as RCD snubber, linearity area work mode, damping resistance circuit, pulse forming lines, PCB deep-hole electroplating power supply, IEDD circuit, etc. which have long turn-off delay time, bad linearity, and related the power supply etc.A novel quasi-resonant current steep pulse transmitting circuits is presented with a device parameters optimizing models. It is concluded that the proposed circuits have less turn-off delay time, eliminating the current over-shot and improving the turn-off consistency, having better linearity. Besides, the energy-feedback circuit can accelerate the ascending of current, cut down the energy loss. Compared to energy-feedback circuit, the energy-dissipation circuit has less turn-off time, better linearity. And, its turn-off delay is incorrelative to transmitting current and supply voltage.A stabilizing voltage clamping high-speed turn-off technique is put forward based on its three forms comprehensively, the energy-dissipation, energy-feedback and lossless stabilizing voltage clamping high-speed turn-off circuit. The proposed circuits product better falling edge performance, shorter turn-off delay, higher falling edge linearity than those reported before. The energy-feedback circuit upgrades the rising-edge and decreases the energy consumption. Furthermore, the feature is independent of load inductance and transmitting current, which resolves the problem of damping resistor optimal matching, which is with domestic and foreign transmitters. The new lossless high-speed turn-off circuit is suitable to reduce the transmitter bulk. In short, lossless stabilizing voltage clamping high-speed turn-off circuit is a ideal TEM pulse current source.The author proposed main-switch, TVS, Sidac-R, RC series, TVS series, IGBT-MOSFET mixture circuit topologies, and analyze the effect on output characteristic in different interdiction diode sites. Aiming at low, middle-level power application and superficial detecting, a TVS based on MOSFET superior topology, a Sidac-R array circuit and time-varying resistor implement arithmetic, and series topologies are proposed correspondingly.A rising-edge stabilizing voltage clamping idea, a rising-edge enhancing stabilizing current source, a phase-shifting controlling strategy and a stabilizing current modulating strategy are proposed, by which current pulse implements linear, high slope rising and stabilizing current. Combined by the rising-edge linear enhancing circuit, output current stabilizing controlling, and stabilizing voltage clamping circuit adequately, a high precision, high slope trapezium pulse current source is designed.Adopted the stabilizing voltage clamping fast turn-off technique, a 10 kW high-power transient electromagnetic transmitter is designed successfully. It is showed that the key parameters such as turn-off delay time, etc., exceeds foreign advanced instrument with higher falling edge linearity and independent of load inductance and transmitting current. The high-power transmitter have been put into production in bulk, which show steady performance, superior quality.Currently, reports about electromagnetic transmitting technologies are still sparse. The author firstly studys the electromagnetic transmitting theory of geological survey field, which is important theoretical and practical values to promote the development of electromagnetic detecting technologies. The research results has partly been producted industrially with good economic and social benefits.