Magnetohydrodynamic angular velocity sensor

Abstract

The application relates to the technical field of non-electric quantity measurement testing, in particular to a magneto-hydrodynamic angular velocity sensor which comprises a cover plate, a shell and a base, wherein the shell is a cylindrical shell body, the inside of the shell body comprises a first cavity and a second cavity, the cover plate covers the upper end of the first cavity, and the base is fixed to the lower end of the second cavity; the inside of the first cavity is provided with an embedded circuit board and a connector, the embedded circuit board is connected with the outside through the connector and is used for outputting a signal to the outside; the inside of the second cavity is provided with a magnetic core assembly, the magnetic core assembly is connected with the embedded circuit board and is used for generating a current signal and transmitting the current signal to the embedded circuit board. The application has the characteristics of simple structure, convenient assembly, high measurement precision, wide frequency band, no mechanical saturation and high reliability, and is a key component for solving the problem of high-bandwidth micro-angle vibration measurement of a spacecraft.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of non-electric quantity measurement testing, in particular to a magneto-hydrodynamic angular velocity sensor. BACKGROUND

[0002] The magneto-hydrodynamic angular velocity sensor can be used for directly measuring high-frequency wideband micro-angle vibration of a spacecraft, and can be used as a core component of an inertial measurement unit and a high-precision fast north seeker of a spacecraft, and can be applied to the fields of earth observation remote sensing, laser communication, directional energy weapons and missiles, and can provide accurate attitude angle change data for attitude stabilization control, and the measurement result can be used for improving image quality of a remote sensing satellite and improving precision of a laser communication satellite and a directional energy weapon.

[0003] A traditional gyroscope of a domestic spacecraft can measure an angular rate below 10 Hz, in recent years, a fiber-optic gyroscope and a laser gyroscope are used for measuring micro-angle vibration of a spacecraft, and the bandwidth is usually below 500 Hz, and there is no sensor for measuring high-frequency micro-angle vibration, the magneto-hydrodynamic angular velocity sensor is a key sensitive component for realizing high-bandwidth (up to 1000 Hz) angular vibration measurement, and there is no magneto-hydrodynamic angular velocity sensor successfully carried on a satellite platform in the prior art, and there is no engineering application magneto-hydrodynamic angular velocity sensor. SUMMARY

[0004] The application provides a magneto-hydrodynamic angular velocity sensor, which has the characteristics of simple structure, convenient assembly, high measurement precision, wide frequency band, no mechanical saturation and high reliability, and is a key component for solving the problem of high-bandwidth micro-angle vibration measurement of a spacecraft.

[0005] In order to achieve the above object, the application provides a magneto-hydrodynamic angular velocity sensor, which comprises a cover plate, a shell and a base, wherein the shell is a cylindrical shell, and the inside of the shell comprises a first cavity and a second cavity, the cover plate covers the upper end of the first cavity, and the base is fixed to the lower end of the second cavity; the inside of the first cavity is provided with an embedded circuit board and a connector, the embedded circuit board is connected with the outside through the connector, and is used for outputting a signal to the outside; the inside of the second cavity is provided with a magnetic core assembly, the magnetic core assembly is connected with the embedded circuit board, and is used for generating a current signal and transmitting the current signal to the embedded circuit board.

[0006] Further, the magnetic core assembly comprises an insulating cylinder, a magnetic conducting cylinder, a current transformer, an electrode column, an upper electromagnetic device and a lower electromagnetic device, wherein the insulating cylinder is located in the inside of the second cavity and is connected with the shell and the base through screws; the electrode column is arranged at the center of the insulating cylinder, the upper end of the electrode column is connected with the upper electromagnetic device, and the lower end of the electrode column is connected with the lower electromagnetic device; the current transformer is arranged around the electrode column and is connected with the embedded circuit board through a signal line; the magnetic conducting cylinder is arranged in the inside of the insulating cylinder and surrounds the current transformer, the upper end of the magnetic conducting cylinder is bonded with the upper electromagnetic device, and the lower end of the magnetic conducting cylinder is bonded with the lower electromagnetic device.

[0007] Further, the upper electromagnetic device comprises an upper electrode plate, an upper magnetic conductor, an upper magnetic sleeve and an upper permanent magnet, wherein the center of the upper electrode plate is connected with the upper end surface of the electrode column through a screw, the upper magnetic conductor is bonded with the upper electrode plate through epoxy resin glue, the upper permanent magnet is bonded with the upper magnetic conductor through epoxy resin glue, and the upper magnetic sleeve is arranged around the upper permanent magnet.

[0008] Further, the lower electromagnetic device comprises a lower electrode plate, a lower magnetic conductor, a lower magnetic sleeve and a lower permanent magnet, wherein the center of the lower electrode plate is connected with the lower end surface of the electrode column through a screw, the lower magnetic conductor is bonded with the lower electrode plate through epoxy resin glue, the lower permanent magnet is bonded with the lower magnetic conductor through epoxy resin glue, and the lower magnetic sleeve is arranged around the lower permanent magnet.

[0009] Further, the upper electrode plate, the lower electrode plate, the magnetic conductor cylinder and the insulating cylinder are bonded together through epoxy resin glue to form a ring-cylinder-shaped cavity.

[0010] Further, the height of the ring-cylinder-shaped cavity is greater than or equal to 25 mm, and the thickness is greater than or equal to 3 mm.

[0011] Further, the ring-cylinder-shaped cavity is filled with a conductive fluid, the conductive fluid is in contact with the upper electrode plate and the lower electrode plate respectively, and the material of the conductive fluid is mercury.

[0012] Further, the material of the shell is soft magnetic alloy, and the soft magnetic alloy forms a ring-shaped radial steady magnetic field with the upper permanent magnet, the lower permanent magnet, the magnetic conductor cylinder and the insulating cylinder.

[0013] Further, the range of the current transformer coil is 1000-10000 turns.

[0014] Further, the built-in circuit board comprises a common-mode rejection circuit, a signal amplification circuit and a low-pass filter circuit, and is used for output signal conditioning, so that the noise of the output signal is less than 300uV.

[0015] The magnetic fluid dynamics angular velocity sensor provided by the application has the following beneficial effects:

[0016] The application can realize micro-angle vibration detection function, has the characteristics of wide frequency band, high precision and high reliability, has simple structure, no mechanical saturation, small signal noise, good linearity, high measurement precision, can be used for directly measuring high-frequency wideband micro-angle vibration of a spacecraft, and can be used as a core component of an inertial measurement unit and a high-precision rapid north seeker of an aircraft. BRIEF DESCRIPTION OF DRAWINGS

[0017] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application and are incorporated in and constitute a part of this application. The embodiments illustrated in the drawings of the application, and their description, are presented to explain the application and are not intended to limit the application unduly. In the drawings:

[0018] Figure 1 is a structural schematic diagram of a magneto-hydrodynamic angular velocity sensor provided according to an embodiment of the present application;

[0019] Figure 2 is a result diagram of bandwidth test of a magneto-hydrodynamic angular velocity sensor provided according to an embodiment of the present application;

[0020] Figure 3 is a result diagram of noise test of a magneto-hydrodynamic angular velocity sensor provided according to an embodiment of the present application;

[0021] Figure 4 is a result diagram of linearity test of a magneto-hydrodynamic angular velocity sensor provided according to an embodiment of the present application;

[0022] In the figure: 1-cover plate, 2-casing, 21-first cavity, 22-second cavity, 3-base, 4-built-in circuit board, 5-connector, 61-insulating cylinder, 62-magnetic conducting cylinder, 63-current transformer, 64-electrode column, 71-upper electrode plate, 72-upper magnetic conductor, 73-upper magnetic sleeve, 74-upper permanent magnet, 81-lower electrode plate, 82-lower magnetic conductor, 83-lower magnetic sleeve, 84-lower permanent magnet, 9-conductive fluid. DETAILED DESCRIPTION

[0023] In order to make the personnel in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should belong to the scope of protection of the present application.

[0024] It should be noted that the terms "first", "second", and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily have to describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0025] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "transverse", "longitudinal" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not intended to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0026] In addition, in addition to indicating the orientation or positional relationship, the above-mentioned partial terms can also be used to indicate other meanings, for example, the term "upper" can also be used to indicate a certain dependent relationship or connection relationship in some cases. For those skilled in the art, the specific meaning of these terms in the present application can be understood according to the specific circumstances.

[0027] In addition, the meaning of the term "a plurality of" should be two and more than two.

[0028] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0029] As shown in Figure 1 The present application provides a magneto-hydrodynamic angular velocity sensor, which comprises a cover plate 1, a shell 2 and a base 3, wherein: the shell 2 is a cylindrical shell, which internally comprises a first cavity 21 and a second cavity 22, the cover plate 1 covers the upper end of the first cavity 21, and the base 3 is fixed to the lower end of the second cavity 22; the first cavity 21 is internally provided with an internal circuit board 4 and a connector 5, the internal circuit board 4 is connected with the outside through the connector 5, and is used for outputting signals to the outside; the second cavity 22 is internally provided with a magnetic core assembly, which is connected with the internal circuit board 4, and is used for generating current signals and transmitting them to the internal circuit board 4.

[0030] Specifically, the magneto-hydrodynamic angular velocity sensor provided by the embodiments of the present application mainly solves the engineering problem of high-bandwidth micro-angle vibration measurement of a spacecraft, can directly measure high-frequency wide-band micro-angle vibration of the spacecraft, can be used as a core component of an inertial measurement unit of a spacecraft and a high-precision fast north seeker, and can be applied to fields such as earth observation remote sensing, laser communication, directional energy weapon, missile and earthquake monitoring, to provide accurate attitude angle change data for attitude stabilization control, and the measurement data can be used to improve image quality of a remote sensing satellite and improve pointing precision of a laser communication satellite and a directional energy weapon. In the embodiments of the present application, the annular radial steady magnetic field is formed between the casing 2 and the magnetic core assembly in the second cavity 22, when measuring, the conductive fluid 9 in the magnetic core assembly performs inertial motion (i.e. angular vibration) in the steady magnetic field to induce an electromotive force, and the electromotive force is formed into a primary circuit through the internal electrode plate and the electrode column 64 to generate a current signal, the current signal is amplified by the current transformer 63 and then output to the built-in circuit board 4 in the first cavity 21, the built-in circuit board 4 detects and processes the current signal, and then outputs the current signal to the outside through the connector 5.

[0031] Further, the magnetic core assembly comprises an insulating cylinder 61, a magnetic conducting cylinder 62, a current transformer 63, an electrode column 64, an upper electromagnetic device and a lower electromagnetic device, wherein: the insulating cylinder 61 is located in the interior of the second cavity 22 and connected with the casing 2 and the base 3 through screws; the electrode column 64 is arranged at the center of the insulating cylinder 61, the upper end is connected with the upper electromagnetic device, and the lower end is connected with the lower electromagnetic device; the current transformer 63 is arranged around the electrode column 64 and connected with the built-in circuit board 4 through a signal line; the magnetic conducting cylinder 62 is arranged in the interior of the insulating cylinder 61 and around the current transformer 63, the upper end is bonded with the upper electromagnetic device, and the lower end is bonded with the lower electromagnetic device; the magnetic core assembly is the core structure of the whole sensor and arranged in the interior of the second cavity 22, and the whole is connected and assembled with the casing 2 and the base 3 through screws, and from the outside to the inside, they are the insulating cylinder 61, the magnetic conducting cylinder 62, the current transformer 63 and the electrode column 64 in sequence, the electrode column 64 is arranged in the middle of the current transformer 63, the upper end surface is connected with the upper electromagnetic device through screws, and the lower end surface is connected with the lower electromagnetic device through screws, to ensure good conduction; the insulating cylinder 61 is used as a cavity shell for packaging the conductive fluid 9, mainly to avoid leakage of the electric signal induced by the conductive fluid 9 to the casing 2; the magnetic conducting cylinder 62 preferably adopts a soft magnetic alloy with high saturation magnetic permeability, and the surface needs to be insulated, that is, an epoxy resin insulating coating is coated on the surface, the thickness of the coating is ≤30um, and the insulation impedance is ≥20MΩ.

[0032] Further, the upper electromagnetic device comprises an upper electrode plate 71, an upper magnetic conductor 72, an upper magnetic sleeve 73 and an upper permanent magnet 74, wherein the center of the upper electrode plate 71 is connected to the upper end surface of the electrode column 64 by a screw; the upper magnetic conductor 72 is bonded to the upper electrode plate 71 by epoxy resin glue; the upper permanent magnet 74 is bonded to the upper magnetic conductor 72 by epoxy resin glue; and the upper magnetic sleeve 73 is arranged around the upper permanent magnet 74. The upper electromagnetic device comprises the upper permanent magnet 74, the upper magnetic conductor 72 and the upper electrode plate 71 which are bonded in sequence from top to bottom, wherein the upper magnetic sleeve 73 is arranged around the upper permanent magnet 74, and the center of the upper electrode plate 71 is connected to the upper end surface of the electrode column 64 for forming a primary induction loop, and the resistance of the connection between the upper electrode plate 71 and the electrode column 64 is ≤1mΩ.

[0033] Further, the lower electromagnetic device comprises a lower electrode plate 81, a lower magnetic conductor 82, a lower magnetic sleeve 83 and a lower permanent magnet 84, wherein the center of the lower electrode plate 81 is connected to the lower end surface of the electrode column 64 by a screw; the lower magnetic conductor 82 is bonded to the lower electrode plate 81 by epoxy resin glue; the lower permanent magnet 84 is bonded to the lower magnetic conductor 82 by epoxy resin glue; and the lower magnetic sleeve 83 is arranged around the lower permanent magnet 84. The lower electromagnetic device comprises the lower permanent magnet 84, the lower magnetic conductor 82 and the lower electrode plate 81 which are bonded in sequence from bottom to top, wherein the lower magnetic sleeve 83 is arranged around the lower permanent magnet 84, and the center of the lower electrode plate 81 is connected to the lower end surface of the electrode column 64 for forming a primary induction loop, and the resistance of the connection between the lower electrode plate 81 and the electrode column 64 is ≤1mΩ.

[0034] Further, the upper electrode plate 71, the lower electrode plate 81, the magnetic conductor cylinder 62 and the insulating cylinder 61 are bonded together by epoxy resin glue to form an annular cylindrical cavity. The bonding site needs to ensure that there is no leakage, i.e. the leakage rate of the bonding site is ≤1.0×10 - 4 Pa·L / s, and the annular cylindrical cavity is mainly used for packaging the conductive fluid 9.

[0035] Further, the height of the annular cylindrical cavity is ≥25mm, and the thickness is ≥3mm. The height and thickness of the annular cylindrical cavity are selected according to the actual design situation.

[0036] Further, the annular cylindrical cavity is filled with a conductive fluid 9, and the conductive fluid 9 is in contact with the upper electrode plate 71 and the lower electrode plate 81 respectively. The material of the conductive fluid 9 is mercury. The conductive fluid 9 is mainly used for the inertial mass unit for sensing angular vibration, and the material is preferably mercury. The magnetic field strength of the conductive fluid 9 cavity is ≥0.1T, and the conductive fluid 9 forms a primary induction loop with the upper electrode plate 71, the lower electrode plate 81 and the electrode column 64. When angular velocity measurement is performed, angular vibration occurs, and the conductive fluid 9 will induce an electromotive force (nanovolt level) under the action of the magnetic field, and then the induced electromotive force will generate a current signal under the action of the primary induction loop.

[0037] Further, the material of the casing 2 is soft magnetic alloy, which forms annular radial steady magnetic field with the upper permanent magnet 74, the lower permanent magnet, the magnetic conducting cylinder 62 and the insulating cylinder 61. The upper permanent magnet 74 and the lower permanent magnet preferably adopt samarium-cobalt type magnet with small temperature coefficient. The annular radial steady magnetic field formed by the upper permanent magnet 74, the lower permanent magnet, the magnetic conducting cylinder 62 and the insulating cylinder 61 is mainly used for generating induced electromotive force of the conductive fluid 9 when angular vibration is performed.

[0038] Further, the range of the coil of the current transformer 63 is 1000-10000 turns. The current transformer 63 is mainly used for amplifying the current signal generated by the primary induced loop. The amplification multiple is proportional to the number of turns of the coil of the current transformer 63. The specific number of turns is designed according to actual measurement. The output signal of the current transformer 63 is millivolt level.

[0039] Further, as shown in Figures 2-4 The built-in circuit board 4 includes common mode rejection circuit, signal amplification circuit and low pass filter circuit, which are used for conditioning the output signal so that the noise of the output signal is less than 300uV. The built-in circuit board is arranged inside the first cavity 21 and is mainly used for conditioning and testing the signal amplified by the current transformer 63 and outputting to the outside through the connector 5. The built-in circuit board 4 is mainly used for common mode noise rejection, secondary amplification and low pass filtering of the amplified signal. The amplification multiple can be set according to actual needs. It is preferably set to 1000 times. The cut-off frequency of the low pass filter is 1000Hz. The built-in circuit board 4 is powered by ±12V DC power supply. The output signal amplitude range is -10V-+10V voltage analog signal, which is proportional to the angular vibration size. The amplitude is calibrated to obtain the sensitivity factor and linearity. In the embodiment of the application, the conditioning of the built-in circuit board 4 makes the noise of the output signal less than 300uV, i.e. the angular rate equivalent noise is less than 5.0×10 -6 rad / s, the equivalent angular displacement noise is less than 5.0×10 -8 rad, the -3dB bandwidth is 2Hz-1000Hz, and the non-linear error is better than 0.25%.

[0040] The above only describes the preferred embodiments of the application and is not used to limit the application. For those skilled in the art, the application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A magneto-hydrodynamic angular rate sensor, characterized by, The utility model relates to a kind of signal generator, including cover plate, cabinet and base, wherein: The cabinet is cylindrical shell, inside including first cavity and second cavity, the cover plate covers the upper end of the first cavity, and the base is fixed in the lower end of the second cavity; The first cavity is internally provided with built-in circuit board and connector, the built-in circuit board is connected with outside through the connector, for output signal to outside; The second cavity is internally provided with magnetic core assembly, the magnetic core assembly is connected with the built-in circuit board, for generating current signal, and transmission to the built-in circuit board; The magnetic core assembly includes insulation cylinder, magnetic conducting cylinder, current transformer, electrode column, upper electromagnetic device and lower electromagnetic device, wherein: The insulation cylinder is located in the inside of the second cavity, and is connected with the cabinet and the base by screw; The electrode column is arranged in the center of the insulation cylinder, and the upper end is connected with the upper electromagnetic device, and the lower end is connected with the lower electromagnetic device; The current transformer is arranged around the electrode column, and is connected with the built-in circuit board by signal line; The magnetic conducting cylinder is arranged in the inside of the insulation cylinder, and is arranged around the current transformer, and the upper end is bonded with the upper electromagnetic device, and the lower end is bonded with the lower electromagnetic device; The upper electromagnetic device includes upper electrode plate, upper magnetic conductor, upper magnetic sleeve and upper permanent magnet, wherein: The center of the upper electrode plate is connected with the upper end surface of the electrode column by screw; The upper magnetic conductor is bonded with the upper electrode plate by epoxy resin glue; The upper permanent magnet is bonded with the upper magnetic conductor by epoxy resin glue; The upper magnetic sleeve is arranged around the upper permanent magnet; The lower electromagnetic device includes lower electrode plate, lower magnetic conductor, lower magnetic sleeve and lower permanent magnet, wherein: The center of the lower electrode plate is connected with the lower end surface of the electrode column by screw; The lower magnetic conductor is bonded with the lower electrode plate by epoxy resin glue; The lower permanent magnet is bonded with the lower magnetic conductor by epoxy resin glue; The lower magnetic sleeve is arranged around the lower permanent magnet; The upper electrode plate, the lower electrode plate, the magnetic conducting cylinder and the insulation cylinder are bonded together by epoxy resin glue, to form annular cylindrical cavity.

2. The magneto-hydrodynamic angular rate sensor of claim 1, wherein, The height of the annular cylindrical cavity is greater than or equal to 25 mm, and the thickness is greater than or equal to 3 mm.

3. The magneto-hydrodynamic angular rate sensor of claim 2, wherein, The annular cylindrical cavity is filled with conductive fluid, the conductive fluid is in contact with the upper electrode plate and the lower electrode plate respectively, and the material of the conductive fluid is mercury.

4. The magnetohydrodynamic angular rate sensor of claim 1, wherein, The material of the cabinet is soft magnetic alloy, which forms a ring-shaped radial steady magnetic field with the upper permanent magnet, the lower permanent magnet, the magnetic conducting cylinder and the insulation cylinder.

5. The magnetohydrodynamic angular rate sensor of claim 1, wherein, The range of the current transformer coil is 1000-10000 turns.

6. The magnetohydrodynamic angular rate sensor of claim 1, wherein, The built-in circuit board includes common-mode rejection circuit, signal amplification circuit and low-pass filter circuit, for output signal conditioning, so that the noise of output signal is less than 300uV.

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