CN-121595355-B - Multi-parallel coil electromagnetic Hopkinson bar and cooperative control method

CN121595355BCN 121595355 BCN121595355 BCN 121595355BCN-121595355-B

Abstract

The application discloses a multi-parallel coil electromagnetic Hopkinson bar and a cooperative control method, wherein the multi-parallel coil electromagnetic Hopkinson bar comprises a controller, a plurality of capacitors, a main coil and a main coil, wherein the controller is used for controlling discharge time of the capacitors, the capacitors are used for discharging according to the discharge time respectively, the main coil is used for responding to discharge of the capacitors to generate corresponding target Lorentz force so as to apply impact load to a tested piece by using the target Lorentz force to complete dynamic mechanical property test of the tested piece, the main coil comprises a plurality of sub-coils which are arranged in a symmetrical annular array, each sub-coil is in an annular spiral structure, any two adjacent sub-coils are different sub-coils, and each capacitor is connected with the corresponding sub-coil.

Inventors

GUO YAZHOU
ZHU HAIQIANG
ZHANG JIALIANG

Assignees

西北工业大学

Dates

Publication Date: 20260508
Application Date: 20260130

Claims (10)

1. A multi-parallel coil electromagnetic hopkinson bar comprising: a controller for controlling discharge times of the plurality of capacitors; the capacitors are respectively used for discharging according to the discharging time; the main coil is used for responding to the discharge of the capacitor and generating corresponding target Lorentz force so as to apply impact load to the tested piece by utilizing the target Lorentz force and finish the dynamic mechanical property test of the tested piece; The main coil comprises a plurality of sub-coils which are arranged in a symmetrical annular array, the distance between every two sub-coils is 1.4mm, a 0.5mm composite insulating layer is arranged between every two adjacent sub-coils, the composite insulating layer is made of epoxy resin, each sub-coil is in an annular spiral structure, two arbitrary adjacent sub-coils are different sub-coils, the two surfaces, facing away from each other, of each sub-coil are respectively provided with an anti-instability component in a laminating mode, the anti-instability components are glass fiber cloth reinforcing layers with the thickness of 0.2mm and the tensile strength of more than or equal to 800MPa, the glass fiber cloth reinforcing layers are solidified through epoxy resin pouring, and each capacitor is connected with the corresponding sub-coil.
2. The multi-parallel coil electromagnetic hopkinson bar set forth in claim 1, further comprising: and the composite insulating layer is used for realizing insulating isolation between adjacent different sub-coils.
3. The multi-parallel coil electromagnetic hopkinson bar set forth in claim 2, further comprising: The anti-instability component is used for inhibiting deformation of the sub-coils under the action of Lorentz force.
4. A multi-parallel coil electromagnetic Hopkinson bar according to claim 3 wherein, The sub-coils are provided with positive and negative electrodes for realizing the electric connection between the sub-coils and the capacitor; The positive electrode of the sub-coil is connected with the positive electrode of the capacitor, and the negative electrode of the sub-coil is connected with the negative electrode of the capacitor.
5. The multi-parallel coil electromagnetic hopkinson bar set forth in claim 4 wherein, The capacitor is a direct discharge type capacitor or an indirect energy storage release type capacitor; the direct discharge type capacitor is used for directly outputting pulse current; The indirect energy storage release type capacitor is connected in series with an inductance compensation module, and the inductance compensation module is used for optimizing pulse current waveforms.
6. The multi-parallel coil electromagnetic hopkinson bar set forth in any one of the claim 1 to 5, wherein, The plurality of sub-coils arranged in a symmetrical annular array in the main coil are positioned on the same plane, or the plurality of sub-coils are not positioned on the same plane.
7. The multi-parallel coil electromagnetic hopkinson bar set forth in claim 6 wherein, The number of turns of each sub-coil is equal to the ratio of the total number of turns of the main coil to the number of sub-coils.
8. The cooperative control method is applied to the multi-parallel coil electromagnetic Hopkinson bar according to any one of claims 1 to 7, and comprises a controller, a plurality of capacitors and a main coil, wherein the main coil comprises a plurality of sub-coils which are arranged in a symmetrical annular array, the distance between each sub-coil is 1.4mm, a 0.5mm composite insulating layer is arranged between every two adjacent sub-coils, the composite insulating layer is epoxy resin, each sub-coil is in a circular spiral structure, any two adjacent sub-coils are different sub-coils, the two facing surfaces of each sub-coil are respectively attached with an anti-instability component, the anti-instability component is a glass fiber cloth reinforcing layer with the thickness of 0.2mm and the tensile strength of more than or equal to 800MPa, the glass fiber cloth reinforcing layer is cured by pouring epoxy resin, and the plurality of capacitors are respectively connected with the plurality of sub-coils, and the method comprises the following steps: Transmitting, by the controller, a discharge control signal to the plurality of capacitors to cause the plurality of capacitors to discharge in response to the discharge control signal; and responding to the discharge of the plurality of capacitors through the main coil, generating a corresponding target Lorentz force, and applying an impact load to the tested piece by utilizing the target Lorentz force so as to complete the dynamic mechanical property test of the tested piece.
9. The cooperative control method of claim 8, wherein the generating, by the primary coil in response to the discharge of the plurality of capacitances, a corresponding target lorentz force comprises: and in the case that the discharge control signal is a synchronous discharge control signal, the main coil responds to synchronous discharge of the plurality of capacitors to generate the target lorentz force based on total current formed by current superposition of the sub-coils.
10. The cooperative control method of claim 8, wherein the generating, by the primary coil in response to the discharge of the plurality of capacitances, a corresponding target lorentz force comprises: And under the condition that the discharge control signal is a time-sharing discharge control signal, responding to time-sharing discharge of the plurality of capacitors according to a preset delay time through the main coil, and superposing the Lorentz force generated by each sub-coil based on the preset delay time to obtain the target Lorentz force.

Description

Multi-parallel coil electromagnetic Hopkinson bar and cooperative control method Technical Field The application relates to the technical field of structural mechanics experimental equipment, in particular to a multi-parallel coil electromagnetic Hopkinson bar and a cooperative control method. Background In the field of dynamic mechanical property testing of materials, an electromagnetic Hopkinson bar is core equipment for realizing high strain rate loading and obtaining extreme environmental mechanical response of the materials, and the performance of the electromagnetic Hopkinson bar directly depends on uniformity of magnetic field generation, controllability of Lorentz force and accuracy of discharge coordination. The core function of the electromagnetic Hopkinson bar depends on transient lorentz force generated by pulse discharge of the main coil to drive a test piece, and the performance of the test piece directly determines the stress wave form, the loading strength and the experimental repeatability. However, in the related art, some electromagnetic hopkinson rods adopting single-coil design are limited by structures, magnetic field distribution gradients are large, effective action areas are narrow, lorentz force peaks are limited, load distribution on a tested piece is uneven, high-strength and uniform impact loading cannot be achieved, some electromagnetic hopkinson rods adopting multi-coil structures have the problems that magnetic field superposition is disordered due to irregular coil arrangement or electromagnetic interference is aggravated due to continuous winding structures, for example, patent CN114965013A proposes a trapezoidal stress wave generator with radial multi-group serial arrangement and parallel circuits, but key defects still exist that main coils are distributed in a radial layering manner (4 groups of coils are distributed from inside to outside), the effective action areas are only expanded to 1.8 times of that of a traditional structure, lorentz force lifting is limited (compared with single coils, only 3.2 times of lifting), trapezoidal stress wave platform section stability is poor (platform section pulse width fluctuation is +/-15%), electromagnetic interference among sub-coils causes waveform distortion rate to be more than or equal to 8%, and patent CN114965013A adopts radial layering arrangement (4 groups of coils are distributed from inside to outside), so that the magnetic field fluctuation is limited to 120 pieces of the lorentz force fluctuation, and the magnetic field fluctuation is limited to the magnetic field fluctuation is not equal to 120. Therefore, how to optimize the structure of the electromagnetic Hopkinson bar improves the uniformity of the magnetic field and the controllability of the Lorentz force, thereby improving the reliability and the stability of the dynamic mechanical test of the material. Disclosure of Invention The application provides a multi-parallel coil electromagnetic Hopkinson bar and a cooperative control method, which optimize the structure of the electromagnetic Hopkinson bar, and improve the uniformity of a magnetic field and the controllability of Lorentz force, thereby improving the performance of dynamic mechanical testing of materials. In order to achieve the above object, the present application provides the following technical solutions: in a first aspect, an embodiment of the present application provides a multi-parallel coil electromagnetic hopkinson bar, including: a controller for controlling discharge times of the plurality of capacitors; the capacitors are respectively used for discharging according to the discharging time; The main coil is used for responding to discharge of the capacitor and generating corresponding target Lorentz force so as to apply impact load to the tested piece by utilizing the target Lorentz force to complete dynamic mechanical property test of the tested piece, wherein the main coil comprises a plurality of sub-coils which are arranged in a symmetrical annular array, each sub-coil is in an annular spiral structure, any two adjacent sub-coils are different sub-coils, and each capacitor is connected with the corresponding sub-coil. In some embodiments of the application, further comprising: the composite insulating layer is used for realizing insulating isolation between adjacent different sub-coils; The composite insulating layer is arranged between the adjacent sub-coils, and the distance between the adjacent sub-coils is a preset distance value. In some embodiments of the application, further comprising: The anti-instability component is used for inhibiting deformation of the sub-coil under the action of Lorentz force; The anti-instability assembly is arranged on the surface of the sub-coil and comprises a glass fiber cloth reinforcing layer with preset thickness and preset tensile strength. In some embodiments of the application, the sub-coils are provided with positive and negative electrodes