CN112512290A - Method for resisting strong electromagnetic interference of electronic controller case of aircraft engine - Google Patents
Method for resisting strong electromagnetic interference of electronic controller case of aircraft engine Download PDFInfo
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- CN112512290A CN112512290A CN202011454566.3A CN202011454566A CN112512290A CN 112512290 A CN112512290 A CN 112512290A CN 202011454566 A CN202011454566 A CN 202011454566A CN 112512290 A CN112512290 A CN 112512290A
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- carbon fiber
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0007—Casings
- H05K9/0015—Gaskets or seals
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
- H05K9/009—Electromagnetic shielding materials, e.g. EMI, RFI shielding comprising electro-conductive fibres, e.g. metal fibres, carbon fibres, metallised textile fibres, electro-conductive mesh, woven, non-woven mat, fleece, cross-linked
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- Engineering & Computer Science (AREA)
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- Electromagnetism (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
The invention relates to the field of cases of electronic controllers of aero-engines, in particular to a method for resisting strong electromagnetic interference of cases of electronic controllers of aero-engines. The method comprises the following steps: s1, carrying out simulation analysis, and evaluating the electromagnetic coupling characteristics of the chassis to obtain the positions of electromagnetic protection weak points; s2, optimizing the material, namely performing nickel plating treatment on the carbon fiber precursor and weaving the carbon fiber precursor into nickel-plated carbon fiber cloth; and S3, compression molding, and integrally molding the case main body material and the shielding material on the basis of S1. S4, protecting the gap, wherein an annular groove is formed in the gap connection position of the box body to provide space for the modularized gap protection material; and S5, assembling, namely, completing the assembly of the cover plate and the box body in a screw fastening mode. The invention has reasonable design and novel structure, can effectively solve the problems of scattered protection measures and lower protection index of the conventional aviation VPX case, enhances the electromagnetic interference resistance and is suitable for wide popularization and application.
Description
Technical Field
The invention relates to the field of cases of electronic controllers of aero-engines, in particular to a method for resisting strong electromagnetic interference of cases of electronic controllers of aero-engines.
Background
The case of the electronic controller of the aero-engine is mostly made of aluminum alloy, and compared with a case made of a composite material, the case has the defects of poor low-frequency protection performance, poor heat insulation performance and heavy quality. In the existing patent "aircraft engine airborne electronic controller case", the idea of using carbon fiber composite material as a case body is mentioned; and in order to improve the shielding effectiveness of the case, chemical nickel plating treatment is carried out on the inner layer and the outer layer of the carbon fiber composite material matrix. The coating process implemented in the patent for improving the shielding effectiveness is difficult to implement, complicated in steps and poor in adhesive force, and affects the surface flatness. Meanwhile, electromagnetic simulation design, gap-specific electromagnetic protection treatment measures and conductive connection modes are not mentioned, and the protection performance needs to be improved.
In addition, the design of the chassis of the electronic controller of the aero-engine generally needs to consider factors such as circuit interface function, installation mode, use environment and the like; in the prior art, electromagnetic compatibility and protection are mainly based on experience design and standardized design, and the problems of lacking design basis, difficult quantification of design indexes and heavy protection measures are solved.
Therefore, it is necessary to solve the above-mentioned technical problems.
Disclosure of Invention
In order to solve the technical problems, the invention provides a method for resisting strong electromagnetic interference of an electronic controller case of an aircraft engine, aiming at the problems of scattered protection measures and lower protection indexes existing in the existing aviation VPX case for solving the electromagnetic interference problem, integrally improving the electromagnetic protection performance of the case and simultaneously realizing the purposes of weight reduction, heat insulation, moisture protection and salt mist protection of the case, and the technical scheme adopted by the invention is as follows:
a method for resisting strong electromagnetic interference of an electronic controller case of an aircraft engine comprises the following steps:
s1, carrying out simulation analysis, and evaluating the electromagnetic coupling characteristics of the chassis to obtain the positions of electromagnetic protection weak points;
s2, optimizing the material, namely performing nickel plating treatment on the carbon fiber precursor and weaving the carbon fiber precursor into nickel-plated carbon fiber cloth;
and S3, compression molding, and integrally molding the case main body material and the shielding material on the basis of S1.
S4, protecting the gap, wherein an annular groove is formed in the gap connection position of the box body to provide space for the modularized gap protection material;
and S5, assembling, namely, completing the assembly of the cover plate and the box body in a screw fastening mode.
Further, the specific step of S1 is:
and performing simulation calculation on the electromagnetic coupling characteristic of the chassis under a strong electromagnetic environment by using a time domain finite integral electromagnetic simulation method, determining an electromagnetic coupling path of the chassis of the electronic controller, and judging the structural size of the electromagnetic interference path and the resonant frequency of the chassis.
Further, the specific step of S2 is:
plating a nickel metal layer on the surface of the carbon fiber precursor by a chemical deposition method, and weaving the nickel-plated carbon fiber cloth.
Further, the specific step of S3 is:
and (4) according to the electromagnetic protection weak point of the case obtained in the step (S1), pre-burying the nickel-plated carbon fiber cloth at the position of the electromagnetic protection weak point, and integrally forming the nickel-plated carbon fiber cloth and the case main body material by a compression molding process.
Further, the specific step of S4 is:
an annular groove is formed in the position of a gap joint of the box body to provide space for the modularized gap protection material, and a water vapor sealing strip and a conductive shielding strip are arranged in the annular groove to provide space for the modularized gap protection material.
Further, the specific step of S5 is:
the bottom plate and the side plate, the side plate and the top plate, the rear plate and the rear end surface, and the front panel and the front end surface of the case are pressed by screws, and conductive adhesive is coated on the screws.
Further, in step S4:
the water vapor sealing strip and the conductive shielding strip are prepared by adopting a rubber co-extrusion technology, and the whole width of the water vapor sealing strip and the conductive shielding strip is matched with the width of the annular groove.
Further, in step S5:
the case is provided with a plug-in orifice for plugging and unplugging the end of the network cable, and the plug-in orifice is provided with a spring type metal component to realize electromagnetic shielding.
Compared with the prior art, the invention has the beneficial effects that:
1. the electromagnetic protection design has pertinence, and the electromagnetic protection design method disclosed by the invention gets rid of the traditional empirical type chassis shielding design method through an advanced electromagnetic coupling simulation technology, solves the electromagnetic shielding problem in a chassis design stage, pre-judges the electromagnetic protection weak point and provides a theoretical basis for the targeted implementation of electromagnetic protection measures.
2. The invention utilizes the metallization enhancement technology of the carbon fiber composite material, breaks through the material instability brought by the metal layer sandwiched between the composite material and the metal plating layer, realizes nickel plating on the carbon fiber precursor by a chemical deposition method, realizes metallization of the nickel-plated carbon fiber, and well overcomes the problems of poor adhesion and easy failure of the traditional shielding metal plating layer by weaving the nickel-plated carbon fiber into the nickel-plated carbon fiber cloth.
3. The invention adopts the case gap modularized protection technology, realizes the integration of shielding and water vapor sealing functions from the perspective of environmental adaptability, and is resistant to moisture and salt mist. The mode of pre-burying the connecting piece at the orifice solves the problem that the connector of the fiber composite material case is difficult to be in complete conductive connection, and ensures the electromagnetic shielding efficiency of the whole case.
4. The invention is provided with the plug-in type gap protection component, and the spring type metal component is arranged at the Ethernet port, so that a port protection measure capable of being plugged and unplugged for many times is formed, the problem of low electromagnetic protection index at the Ethernet port is solved, and the electromagnetic shielding efficiency of the Ethernet port is improved.
In conclusion, the aerial VPX case has the advantages of reasonable design and novel structure, can effectively solve the problems of scattered protection measures and low protection index of the existing aerial VPX case, enhances the electromagnetic interference resistance, and is suitable for wide popularization and application.
Drawings
FIG. 1 is a schematic structural diagram of a main body shielding material of a chassis in the prior art;
FIG. 2 is a schematic structural diagram of a main body shielding material of a case according to the present invention;
FIG. 3 is a schematic view of a protection structure for the connection position of the case according to the present invention;
FIG. 4 is a schematic diagram of the protection of the plug-in structure of the present invention;
FIG. 5 is a schematic view of an external screw fixing structure;
FIG. 6 is a schematic view of an internal screw fastening structure;
in the figure: 1 is a nickel metal layer, 2 is carbon fiber, 3 is a water vapor sealing strip, 4 is a conductive shielding strip, and 5 is a spring type metal structural member.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1 to 6, the invention provides a method for resisting strong electromagnetic interference of a chassis of an electronic controller of an aircraft engine, which combines a chassis electromagnetic coupling characteristic simulation technology, an electromagnetic enhanced carbon fiber integrated forming process and a modular conductive connection processing technology, and adopts CST commercial software innovatively in a design stage to evaluate the electromagnetic coupling characteristic of the chassis, obtain the electromagnetic protection weak point and quantify the electromagnetic protection index. In the manufacturing stage, the carbon fiber precursor is innovatively subjected to nickel plating treatment, and the woven nickel-plated carbon fiber cloth finished product is used as a main material for the integral forming of the high-performance shielding case, so that the problem of adhesive force is solved. And the compression molding process is adopted, so that the manufacturing precision is high, and the requirement of the VPX case on the dimensional precision is met. Meanwhile, the integrated co-extrusion conductive rubber is designed, and the electromagnetic protection problem of the box body gap and the connector port is solved by adopting a modularized conductive connection technology. The concrete parts comprise:
simulation analysis
1) And setting simulation parameters. And setting an excitation source and a polarization mode, and performing electromagnetic simulation calculation respectively. The boundary condition adopts an open boundary to simulate a darkroom dead zone environment.
2) And analyzing the electromagnetic coupling path of the case. An electromagnetic field analysis module in CST software is utilized to simulate the distribution condition of an electromagnetic field in a computer case, analyze a potential electromagnetic coupling path and determine the weak point of electromagnetic protection.
3) And calculating the shielding effectiveness of the case. And (3) setting an electric field probe at a key focus position in the case, and carrying out simulation calculation on the test calibration value and the electric field test value in the case. And according to the shielding effectiveness definition, the shielding effectiveness of the important focus position in the computer case.
4) And designing a case structure according to the simulation result.
(II) optimization of main body material and compression molding
On the basis of simulation analysis, fiber metallization enhancement and structure integrated forming design are carried out aiming at the electromagnetic characteristics of the main material of the case. The electrical conductivity of the ordinary carbon fiber 2 is low, and the shielding design of high field intensity is not enough after molding. According to the technology, firstly, a nickel metal layer 1 (or a combined metal layer) is plated on the surface of carbon fiber through a chemical deposition method, nickel-plated carbon fiber cloth is woven, and then an electromagnetic protection material and a case main body material are integrally formed through a compression molding process and a method for embedding a protection part.
Through the carbon fiber metallization and reinforcement integrated forming technology, the problem of weak electromagnetic property of the carbon fiber material is solved, and the problem of effective electric continuous combination of the composite material and the protector component is also solved.
(III) modularized gap protection technology
1) On the basis of simulation analysis, a modularized gap protection technology is adopted for connecting gaps of main body plates, and a machine case bottom plate and a side plate, a side plate and a top plate, a rear plate and a rear end face, and a front plate and a front end face are adopted. And conducting rubber is adopted for gap protection. Through seting up the ring channel, built-in modularization conductive rubber to it is fixed with the conducting resin, recycle the screw and compress tightly, thereby realize the electrically conductive continuity in gap, conductive rubber includes steam sealing strip and electrically conductive shielding strip, the steam sealing strip adopts rubber coextrusion technique preparation with electrically conductive shielding strip, the whole width of steam sealing strip and electrically conductive shielding strip and the width looks adaptation of ring channel.
2) The screwed connection includes that outside screw is fixed, inside screw is fixed and link up no fixed connection fixed mode, wherein:
when external screw, inside screw are fixed, set up conductive rubber and cross the screw fastening between connector and the fixed unit, and the screw surface coating conductive rubber, show according to the simulation result that the electromagnetic energy coupling of ethernet mouth is the most serious. The reason is that the network port adopts a plug-in installation mode, so that the continuity of the electric conduction is poor. Therefore, the invention is provided with a through non-fixed connection mode, and a metal spring type structural member is arranged at the connection position of the Ethernet port for gap protection design, thereby solving the electromagnetic protection problem of a plug-in installation mode.
Although only the preferred embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art, and all changes are encompassed in the scope of the present invention.
Claims (8)
1. A method for resisting strong electromagnetic interference of an electronic controller case of an aircraft engine is characterized by comprising the following steps: the method comprises the following steps:
s1, carrying out simulation analysis, and evaluating the electromagnetic coupling characteristics of the chassis to obtain the positions of electromagnetic protection weak points;
s2, optimizing the material, namely performing nickel plating treatment on the carbon fiber precursor and weaving the carbon fiber precursor into nickel-plated carbon fiber cloth;
and S3, compression molding, and integrally molding the case main body material and the shielding material on the basis of S1.
S4, protecting the gap, wherein an annular groove is formed in the gap connection position of the box body to provide space for the modularized gap protection material;
and S5, assembling, namely, completing the assembly of the cover plate and the box body in a screw fastening mode.
2. The method for resisting strong electromagnetic interference of the chassis of the electronic controller of the aero-engine as claimed in claim 1, wherein the specific steps of S1 are as follows:
and performing simulation calculation on the electromagnetic coupling characteristic of the chassis under a strong electromagnetic environment by using a time domain finite integral electromagnetic simulation method, determining an electromagnetic coupling path of the chassis of the electronic controller, and judging the structural size of the electromagnetic interference path and the resonant frequency of the chassis.
3. The method for resisting strong electromagnetic interference of the chassis of the electronic controller of the aero-engine as claimed in claim 1, wherein the specific steps of S2 are as follows:
plating a nickel metal layer on the surface of the carbon fiber precursor by a chemical deposition method, and weaving the nickel-plated carbon fiber cloth.
4. The method for resisting strong electromagnetic interference of the chassis of the electronic controller of the aero-engine as claimed in claim 1, wherein the specific steps of S3 are as follows:
and (4) according to the electromagnetic protection weak point of the case obtained in the step (S1), pre-burying the nickel-plated carbon fiber cloth at the position of the electromagnetic protection weak point, and integrally forming the nickel-plated carbon fiber cloth and the case main body material by a compression molding process.
5. The method for resisting strong electromagnetic interference of the chassis of the electronic controller of the aero-engine as claimed in claim 1, wherein the specific steps of S4 are as follows:
an annular groove is formed in the position of the joint of the box body gap to provide space for the modularized gap protective material, and a water vapor sealing strip and a conductive shielding strip are arranged in the annular groove.
6. The method for resisting strong electromagnetic interference of the chassis of the electronic controller of the aero-engine as claimed in claim 1, wherein the specific steps of S5 are as follows:
the bottom plate and the side plate, the side plate and the top plate, the rear plate and the rear end surface, and the front panel and the front end surface of the case are pressed by screws, and conductive adhesive is coated on the screws.
7. The method for resisting strong electromagnetic interference of the case of the electronic controller of the aero-engine as claimed in claim 5, wherein in the step S4:
the water vapor sealing strip and the conductive shielding strip are prepared by adopting a rubber co-extrusion technology, and the whole width of the water vapor sealing strip and the conductive shielding strip is matched with the width of the annular groove.
8. The method for resisting strong electromagnetic interference of the chassis of the electronic controller of the aero-engine as claimed in claim 6, wherein in the step S5:
the case is provided with a plug-in orifice for plugging and unplugging the end of the network cable, and the plug-in orifice is provided with a spring type metal component to realize electromagnetic shielding.
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| CN202011454566.3A CN112512290A (en) | 2020-12-10 | 2020-12-10 | Method for resisting strong electromagnetic interference of electronic controller case of aircraft engine |
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| CN202011454566.3A CN112512290A (en) | 2020-12-10 | 2020-12-10 | Method for resisting strong electromagnetic interference of electronic controller case of aircraft engine |
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Cited By (2)
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| WO2024160585A1 (en) * | 2023-02-03 | 2024-08-08 | Wieland-Werke Ag | Cooling system for the liquid immersion cooling of electronic components |
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