Large Magnetic Moment Transmitter with Bipolar Trapezoidal Current and Its Current Generation Method

Abstract

The invention discloses a bipolar trapezoidal current large magnetic moment transmitter and a current generation method thereof, and relates to the technical field of aerial transient electromagnetic exploration. The transmitter of the present invention includes: trapezoidal current constant voltage clamping circuit, current overshoot suppression circuit, transmitter main control circuit and other parts, the present invention adopts the trapezoidal current constant voltage clamping circuit based on passive constant voltage clamping method , which realizes the fast and linear turn-off of the current falling edge, and at the same time, the rapid and linear increase of the current rising edge, thus forming a bipolar trapezoidal current; in addition, combined with the design of the current overshoot suppression circuit, the damping resistor action time is controlled, which can effectively eliminate the current Tail oscillation; finally, the present invention proposes a bipolar trapezoidal current generation method based on the transmitter, which has very important application significance for further improving the quality of the transmitting current waveform and improving the detection performance of the aerial transient electromagnetic exploration system .

Description

technical field [0001] The invention relates to the technical field of aerial transient electromagnetic exploration, in particular to a bipolar trapezoidal current large magnetic moment transmitter and a current generation method thereof. Background technique [0002] The airborne transient electromagnetic prospecting system is one of the important means to detect electrical abnormal ore bodies, especially metal mines. It has the characteristics of low cost, high speed and good trafficability. Rapid resource evaluation can realize rapid exploration of large-scale mineral resources, and its flying platforms mainly include fixed-wing aircraft and helicopters. The airborne transient electromagnetic method is a time-domain artificial source electromagnetic detection method based on electromagnetic induction. The pulse current is sent underground through the multi-turn coil suspended under the aircraft to generate a pulse magnetic field (primary field). Under the excitation of t...

AI Technical Summary

Problems solved by technology

[0008] The traditional waveform current transmitter and current generation method in the airborne transient electromagnetic exploration system have the following technical defects: 1) In the case of a large equivalent inductance of the transmitting coil, if the transmission current is required to be as high as hundreds of amperes, the power consumption The time is quite long, and it takes hundreds of milliseconds to reach the current peak value, that is, the rising edge of the current cannot be rapidly increased; although the method of capacitor energy storage can effectively increase the rising time of the current, the falling edge of the emission current is exponentially and slowly decreasing; 2 ) The damping resistance of the current overshoot suppression circuit is connected in parallel at both ends of the transmitting coil at all times, which will increase the power consumption of the transmitter, which does not meet the requirements of efficient energy utilization of aviation transient electromagnetic systems

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