Electric source five-level transmission circuit employing transient electromagnetic method

Abstract

The invention relates to an electric source five-level transmission circuit employing a transient electromagnetic method. The electric source five-level transmission circuit is formed by connecting a control and protection circuit to an earth load through a three-phase controllable rectifier circuit, a DC / DC and a five-level transmission bridge circuit. The electric source five-level transmission circuit is characterized in that the five-level transmission bridge circuit is connected to a reference frequency generation circuit through a drive and protection circuit, a synthesis circuit and a frequency dividing circuit, and the synthesis circuit is connected to a rising edge control circuit, a falling edge control circuit, a flat-top control circuit and a synchronous circuit. The bearable highest voltage of each power device in the circuit is 1 / 4 of a direct current bus voltage; an improved five-level topology clamps the voltage of a clamping diode within a single level; the problem of reverse recovery of multi-level output clamping diodes is solved; when any level is output from the circuit, eight MOSFETs are kept at an on state and eight MOSFETs are turned off; and the adjacent levels are switched only by switching two MOSFETs, so that good stability is ensured. Compared with conventional equipment, the electric source five-level transmission circuit is low in value of dv / dt; and insulation impact and electromagnetic interference are reduced.

Description

technical field [0001] The invention relates to an electrical detection instrument in transient electromagnetics, in particular to a transmitting circuit of a high-voltage and high-frequency high-power electrical detection instrument. Background technique [0002] The principle of transient electromagnetic detection is to determine the underground structure by forming a changing magnetic field in the earth through an electrical source or a magnetic source, and calculating the resistivity and other parameters of the underground medium through the secondary field induced by the changing magnetic field. Purpose. The depth of transient electromagnetic detection is generally positively correlated with the intensity of the transmitted signal. The higher the transmission voltage, the deeper the detection depth. The detection accuracy is positively correlated with the frequency of the transmitted signal, and the stronger the frequency of the transmitted signal, the more accurate th...

AI Technical Summary

Problems solved by technology

The main feature is that the output frequency of the circuit is very high so that the output of high voltage can still be maintained, which solves the problem of voltage distribution on the clamping diode

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