CN-122025335-A - Trapezoidal collapsible solenoid device in seabed

Abstract

The invention relates to a seabed trapezoid foldable electromagnetic coil device, which belongs to the technical field of ocean electromagnetic detection and comprises a main bearing beam, an expandable transmitting coil assembly, a receiving coil assembly, a transmission connecting rod, a hinged rotating seat, a sliding connecting seat and a push-pull driving rod, wherein the transmitting coil is of a symmetrical distributed trapezoid structure, the receiving coil is in sliding fit with the main bearing beam through the sliding connecting seat, the push-pull driving rod is used for linking the movement of the receiving coil and the unfolding/folding of the transmitting coil, and a device frame adopts a macromolecular nonmagnetic material and ferromagnetic driving parts to avoid the arrangement. According to the invention, plane magnetic field balance of the receiving coil is realized through the non-uniform magnetic field design of the trapezoidal transmitting coil, the space optimal configuration of the coil is completed by utilizing the linkage mechanism, meanwhile, the folding portability and the anti-interference performance of the multi-layer coil are realized, the direct coupling of the primary field of the transmitting coil to the receiving is effectively inhibited, the stability and the signal to noise ratio of the detection signal are improved, and the method is suitable for complex submarine transient electromagnetic detection scenes carried by AUV/ROV.

Inventors

• ZHANG XUETING
• Ye Wanheng
• MENG YIPENG
• REN KANGJIE
• HUANG YONGKAI
• HUANG PEI

Assignees

• 杭州电子科技大学

Dates

Publication Date

20260512

Application Date

20260331

Claims (7)

1. 1. A subsea trapezoidal foldable electromagnetic coil apparatus, comprising: The main bearing beam is longitudinally arranged along the device and is a supporting foundation of an integral structure; The expandable transmitting coil assemblies are symmetrically arranged on two sides of the main bearing beam, and transmitting coils with trapezoid structures are fixedly arranged on the expandable transmitting coil assemblies; the receiving coil assembly is in sliding connection with the main bearing beam through the sliding connection seat, moves along the axial direction of the main bearing beam and is used for receiving secondary induction electromagnetic signals of the submarine underground medium; One end of the transmission connecting rod is hinged with the sliding connecting seat, and the other end of the transmission connecting rod is hinged with the expandable transmitting coil assembly through the hinged rotating seat; the hinged rotating seat is fixed on the frame of the expandable transmitting coil assembly; And one end of the push-pull driving rod is connected with the receiving coil assembly and is used for driving the receiving coil assembly to axially move along the main bearing beam, and the telescopic movement of the push-pull driving rod can synchronously realize the axial movement of the receiving coil assembly and the expansion or folding of the expandable transmitting coil assembly through the linkage of the sliding connecting seat and the transmission connecting rod.
2. 2. The foldable electromagnetic coil assembly of claim 1, wherein the transmitter coil is a symmetrically distributed trapezoid, the wider end of the trapezoid transmitter coil is farther from the receiver coil assembly than the narrower end, so that the distribution of the magnetic field near the plane of the receiver coil assembly tends to be balanced, and when the trapezoid transmitter coils on both sides are unfolded to a working angle, the magnetic fluxes generated by the coil currents form a mutual cancellation area near the plane of the receiver coil assembly.
3. 3. The foldable electromagnetic coil apparatus of claim 1, wherein the receiving coil assembly is configured to move along with the expansion of the expandable transmitting coil assembly to a predetermined position with small primary field strength and balanced magnetic field distribution, thereby realizing a spatially optimized configuration of the transmitting-receiving coil.
4. 4. The foldable electromagnetic coil apparatus of claim 1, wherein the main carrier beam and the frame of the expandable transmitting coil assembly are made of a polymer non-magnetic material, and the polymer non-magnetic material is engineering plastic or a composite material, so that magnetization effect of the structure is avoided.
5. 5. A subsea trapezoidal foldable electromagnetic coil device according to claim 1, wherein said push-pull drive rod is a drive member comprising ferromagnetic material mounted in a primary field-affected minimum area near the plane of the receiver coil assembly.
6. 6. The foldable seafloor trapezoid electromagnetic coil apparatus of claim 1, wherein the apparatus is of a compact overall structure when the expandable transmission coil assembly is folded, and wherein the trapezoidal transmission coils on both sides are of a symmetrical open structure when expanded, thereby forming an operating magnetic field adapted to seafloor transient electromagnetic detection.
7. 7. The device of claim 1, wherein the magnetic moment of the transmitter coil satisfies the formula: wherein In order to transmit the magnetic moment of the coil, 1 For the number of turns of the transmit coil, For the coil current to be present, The induction voltage of the receiving coil meets the formula: wherein In order to receive the number of turns of the coil, In order to accept the effective area of the coil, Is the planar magnetic induction intensity of the coil.

Description

Trapezoidal collapsible solenoid device in seabed Technical Field The invention relates to a seabed trapezoid foldable electromagnetic coil device, which is particularly suitable for being mounted on an AUV (autonomous underwater robot)/ROV (remote-controlled underwater robot) and applied to a transient electromagnetic method detection scene of a complex seabed environment, and belongs to the technical field of ocean electromagnetic detection. Background The ocean electromagnetic detection technology is one of core technologies of ocean geophysical detection and is widely applied to the fields of ocean resource development and ocean engineering detection such as ocean oil and gas resource exploration, ocean hydrothermal mineral exploration, submarine pipeline and submarine cable positioning identification and the like. The transient electromagnetic method (TRANSIENT ELECTROMAGNETIC METHOD, TEM) is a main stream method of electromagnetic detection in land and shallow sea areas by virtue of the advantages of sensitivity to underground electrical structures, large detection depth, strong noise immunity, no need of grounding and the like, and the application requirements in the field of ocean detection are increasingly improved. The transient electromagnetic method has the core principle that pulse current is emitted to underground or submarine medium through a transmitting coil, when the pulse current is suddenly turned off, an induced vortex field is excited in the underground medium, the vortex field is gradually attenuated along with time, the attenuation characteristic of the induced vortex field and the conductivity distribution of the underground medium are in strong correlation, an attenuation curve of induced voltage along with time is recorded by a receiving coil, and the electrical structure information of the underground medium can be obtained through data inversion, so that detection and identification of a submarine target body are realized. However, the ocean environment and the land environment have intrinsic difference, seawater has higher conductivity (usually 3-5S/m), strong attenuation and shielding effects on electromagnetic signals, and meanwhile, the electrical difference of target bodies such as a submarine sediment layer, a submarine cable, a mineral body and the like can also have complex influence on transient electromagnetic response, so that the submarine transient electromagnetic method is far more complex than land application in theoretical modeling, signal acquisition structural design and data processing methods. At present, the submarine transient electromagnetic detection system is mainly divided into three types, namely a towed transmitting-receiving system, a submarine laying type receiving node system and an AUV/ROV carrying type electromagnetic detection system, wherein the AUV/ROV carrying type electromagnetic detection system is a preferable scheme for detecting a deep sea complex environment due to the advantages of strong maneuverability, high detection efficiency, adaptation to complex submarine topography and the like. For an AUV/ROV carrying electromagnetic detection system, an electromagnetic coil of a core component is divided into a transmitting coil and a receiving coil, and the existing coil structure is mainly divided into two types, namely a single-layer coil structure with a central loop, a coaxial loop or an overlapped loop, and a multi-layer coil structure (such as an equivalent anti-magnetic flux structure) with a plurality of transmitting/receiving coils overlapped. However, when the conventional coil structure is applied to AUV/ROV-carried submarine transient electromagnetic detection, the technical defect that the anti-interference performance and portability cannot be considered exists is that the following specific problems are caused: 1. Although the multi-layer coil structure realizes stronger electromagnetic interference resistance through multi-coil superposition and can effectively inhibit primary field noise, the structure is large in size and fixed in structure, is difficult to adapt to the limited carrying space of an AUV/ROV, has extremely poor trafficability of transportation and submarine arrangement, and cannot meet the detection requirement of complex submarine topography; 2. Although the single-layer coil structure is compact in structure and convenient to carry, the electromagnetic interference resistance is weak, and primary field signal noise generated by a transmitting coil in the detection process is too large, so that a receiving coil is extremely easy to capture early attenuation signals, early signal loss is caused, and the integrity and inversion accuracy of detection data are seriously affected; 3. the relative positions of the transmitting coil and the receiving coil of the existing coil structure are fixed, dynamic adjustment cannot be carried out according to the submarine detection environment and magnetic field distribut