An electromagnetic compatibility structure suitable for a high magnetic field environment of a pure electric heavy truck

Abstract

The utility model discloses a kind of applicable pure electric heavy truck high magnetic field environment electromagnetic compatibility structure, adopt composite shielded wiring harness structure, driving area shielding structure and chassis area shielding structure collaborative vehicle level solution scheme.Composite shielded wiring harness is shielded to high-voltage power wiring harness and low-voltage signal wiring harness, driving area shielding structure provides shielding protection for vehicle controller, integrated instrument, chassis area shielding structure is shielded to power electronic unit, gearbox controller and battery pack, and driving area shielding structure and chassis area shielding structure are realized signal and electric energy stable transmission and shielding cooperation by composite shielded wiring harness structure.The structure effectively solves the problems of traditional scheme, such as lack of system, lack of low-frequency strong magnetic protection, greatly improve the running stability and safety of vehicle in high magnetic environment, implementation difficulty is low, cost is controllable, easy to industrialization application.

Description

Technical Field

[0001] This utility model relates to the field of new energy vehicle technology, specifically to an electromagnetic compatibility structure suitable for high magnetic field environments of pure electric heavy trucks. Background Technology

[0002] Large-scale industrial settings such as aluminum electrolysis involve strong magnetic fields with strengths exceeding 1300 Gs, which can be steady-state or quasi-steady-state. Under such conditions, critical electronic systems of ordinary pure electric heavy-duty trucks, such as the vehicle control unit (VCU), power electronic unit (PEU), and sensors, are susceptible to interference from strong magnetic fields.

[0003] While some existing technologies address localized electromagnetic interference issues in vehicles, most suffer from the following limitations: shielding methods are often simplistic, focusing primarily on electric field shielding or high-frequency interference filtering, offering limited protection against magnetic field interference. Furthermore, they lack a systematic approach, often offering patchwork solutions for individual components or wiring harnesses, failing to implement top-level electromagnetic compatibility design and layout optimization at the vehicle system level.

[0004] Therefore, a vehicle-level electromagnetic compatibility structure that can effectively cope with low-frequency strong magnetic field environments is needed to ensure the operation and promotion of pure electric heavy trucks in such special scenarios. Utility Model Content

[0005] The present invention aims to provide an electromagnetic compatibility structure suitable for high magnetic field environments of pure electric heavy trucks, in order to solve the problems mentioned above.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An electromagnetic compatibility structure suitable for high magnetic field environments of pure electric heavy-duty trucks includes a composite shielded wiring harness structure, a driver's area shielded structure, and a chassis area shielded structure. The composite shielded wiring harness structure is used for shielding and protecting the high-voltage power wiring harness and the low-voltage signal wiring harness. The driver's area shielded structure is used for shielding and protecting the vehicle controller and integrated instruments. The chassis area shielded structure is used for shielding and protecting the power electronics unit, the transmission controller, and the battery pack. The driver's area shielded structure and the chassis area shielded structure are connected by the composite shielded wiring harness structure.

[0007] Furthermore, the composite shielded wire harness structure comprises, from the inside out, a conductor, an inner insulating sheath, a middle high-permeability shielding layer, and an outer metal braided mesh; the conductor is made of high-purity electrolytic copper, with a conductor cross-sectional area of ​​50-120 mm² for high-voltage power wire harnesses and 0.5-2.5 mm² for low-voltage signal wire harnesses; the inner insulating sheath is made of cross-linked polyethylene or polyvinyl chloride with a thickness of 0.8-1.5 mm; the middle high-permeability shielding layer is made of permalloy foil or nanocrystalline tape, processed by overlapping wrapping with a wrapping overlap rate of not less than 50%; the outer metal braided mesh is woven from tin-plated copper wire with a braiding coverage rate of not less than 85%.

[0008] Furthermore, the composite shielded wire harness structure is provided with a copper crimping ring at the connection end with the driver area shielding structure and the chassis area shielding structure; the outer metal braided mesh of the composite shielded wire harness structure and the middle high magnetic permeability shielding layer are folded together into the metal interface of the driver area shielding structure or the chassis area shielding structure, and are crimped and fixed by the crimping ring to form a 360° low impedance overlap, with a resistance of less than 10mΩ at the overlap.

[0009] Furthermore, the driver area shielding structure includes a closed shielding shell, conductive foam, and an insulating bracket; the shielding shell is welded from a 1-1.5mm thick low-carbon steel plate, and has a composite shielded wiring harness interface and louvered ventilation holes on it; the conductive foam is pasted on the inside of the shielding shell, has a thickness of 2-3mm, and a surface resistivity of no more than 10Ω; the insulating bracket is made of engineering plastic and is fixed inside the shielding shell for installing the vehicle control unit (VCU) and integrated instruments.

[0010] Furthermore, the driving area shielding structure also includes a multi-strand copper grounding wire; the cross-sectional area of ​​the copper grounding wire is not less than 6mm², one end is connected to the shielding shell, and the other end is connected to the grounding post of the pure electric heavy truck body, and the grounding resistance of the grounding post of the vehicle body is not greater than 1Ω.

[0011] Furthermore, the chassis area shielding structure includes a PEU shielding unit, a TCU shielding unit, a battery pack shielding unit, and a copper busbar. The PEU and TCU shielding units are semi-enclosed structures, made of 0.8-1.2mm thick permalloy plate, and both have composite shielded wire harness interfaces and ventilation holes. The battery pack shielding unit includes an aluminum foil pasted on the inside of the battery pack shell and a permalloy shielding cover installed on the outside of the battery pack BMS circuit board. The copper busbar has a cross-sectional area of ​​10mm² and is used to connect the PEU shielding unit, the TCU shielding unit, and the battery pack shielding unit to form a chassis shielding network.

[0012] Furthermore, the chassis area shielding structure is connected to the vehicle body grounding post through a multi-strand copper grounding wire, and the cross-sectional area of ​​the copper grounding wire is not less than 8mm²; the driver area shielding structure and the chassis area shielding structure share the vehicle body grounding post, and the shielding continuity is achieved through a composite shielding harness structure, which together control the magnetic field strength inside the vehicle controller (VCU), power electronics unit (PEU), and transmission controller (TCU) to below 50Gs.

[0013] This utility model has the following beneficial effects: A collaborative protection system consisting of a composite shielded wiring harness structure, a driver area shielding structure, and a chassis area shielding structure is provided to achieve full-scenario shielding of core components and wiring harness links in the driver area and chassis area. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the composite shielded wire harness structure mentioned in this utility model.

[0015] Figure 2 This is a schematic diagram of the optimized layout of the vehicle controller mentioned in this utility model. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings and relevant knowledge. Obviously, the described applications are only some embodiments of the present invention, and not all embodiments.

[0017] The present invention will be further described in detail below with reference to the accompanying drawings.

[0018] Reference Figure 1 , Figure 2 As shown, an electromagnetic compatibility structure suitable for high magnetic field environments of pure electric heavy-duty trucks includes a composite shielded wiring harness structure 1, a driver area shielded structure 2, and a chassis area shielded structure 3. The composite shielded wiring harness structure 1 is used for shielding and protecting the high-voltage power wiring harness and the low-voltage signal wiring harness. The driver area shielded structure 2 is used for shielding and protecting the vehicle controller 13 and the integrated instrument 4. The chassis area shielded structure 3 is used for shielding and protecting the power electronic unit 5, the gearbox controller 6, and the battery pack 7. The driver area shielded structure 2 and the chassis area shielded structure 3 are connected through the composite shielded wiring harness structure 1.

[0019] This utility model aims to solve the technical problems of incomplete shielding coverage, poor system coordination, and insufficient protection against low-frequency strong magnetic fields in existing electromagnetic protection solutions for pure electric heavy trucks. It provides a collaborative protection system consisting of a composite shielded wiring harness structure, a driver area shielding structure, and a chassis area shielding structure. This system achieves full-scene shielding of core components and wiring harness links in the driver area and chassis area, ensuring stable and safe operation of the vehicle in strong magnetic field environments above 1300Gs.

[0020] Specifically, by employing a composite shielded wiring harness with both conductive and magnetic layers, along with localized magnetic shielding of the controller, low-frequency strong magnetic field interference, which is difficult to address with traditional solutions, is effectively mitigated, fundamentally preventing vehicle malfunctions in high magnetic environments. Through hardware synergy between wiring harness shielding and controller layout and shielding, a vehicle-level electromagnetic protection foundation is constructed, significantly improving the vehicle's applicability in extreme environments. By optimizing the controller layout, the vehicle's own spatial magnetic field distribution characteristics are cleverly utilized, achieving a substantial reduction in the magnetic exposure level of key components at the lowest cost. Furthermore, both the composite shielded wiring harness and the magnetic shielding cover utilize mature technologies; the layout optimization is based on the existing vehicle architecture, making implementation simple, cost-effective, and easy to industrialize.

[0021] Further optimization yields a composite shielded wire harness structure, employing a four-layer composite structure, from the inside out as follows: Conductor 8: Made of high-purity electrolytic copper, the cross-sectional area of ​​the high-voltage power harness conductor is 50-120mm², and the cross-sectional area of ​​the low-voltage signal harness conductor is 0.5-2.5mm² (compatible with CAN / LIN bus signal transmission). Its core function is to stably transmit electrical energy (high-voltage harness) or control signals (low-voltage harness), while providing a shielded continuity channel for the shielding structure of the driving area and chassis area. Inner insulating sheath 9: Extruded from cross-linked polyethylene or polyvinyl chloride material, with a thickness of 0.8-1.5mm, it has the characteristics of temperature resistance and oil resistance, realizes electrical insulation between the conductor and the external structure, prevents leakage accidents, and protects the conductor from mechanical wear. The intermediate high-permeability shielding layer 10 is made of permalloy foil (nickel-iron alloy, permeability ≥8000μH / m) or nanocrystalline ribbon (iron-based nanocrystalline alloy, permeability ≥10000μH / m) in an overlapping wrapping manner, with a wrapping overlap rate of not less than 50% (the overlap width of adjacent material layers is ≥50%). This layer utilizes the magnetic shunting effect of the high-permeability material to guide the external low-frequency strong magnetic field to form a magnetic path within itself, significantly reducing the intensity of the magnetic field penetrating to the inner conductor and avoiding magnetic field-induced interference signals within the wire bundle. It is the core layer for dealing with low-frequency strong magnetic interference. Outer metal braided mesh 11: It is woven from tin-plated copper wire with a diameter of 0.1-0.2mm, and the braiding coverage is not less than 85%. It has two functions: first, to reflect and absorb high-frequency electromagnetic interference; second, to serve as a grounding layer, connecting the intermediate shielding layer with the metal shell of the shielding structure of the driving area and chassis area to form a full-area grounding network and ensure that interference signals are quickly discharged.

[0022] At the connection point with the shielding structure of the driving area and chassis area, the composite shielded wire harness adopts a 360° low impedance overlap design: the outer metal braided mesh and the middle high magnetic permeability shielding layer are folded together into the metal interface of the shielding structure and fixed by a copper crimping ring (thickness 1.2-1.5mm). After crimping, the resistance at the overlap is ≤10mΩ, ensuring the shielding continuity between the wire harness and the shielding structure of the two areas and preventing interference from entering from the connection gap.

[0023] Further optimized, the driver area shielding structure 2 provides shielding protection for the vehicle control unit (VCU) 13 and integrated instrument cluster 4 within the driver area, and is connected to the chassis area shielding structure via a composite shielded wiring harness, specifically including: Shielding housing: Made of 1-1.5mm thick low carbon steel plate welded into shape, the whole is a closed structure (only the composite shielded wire harness interface is reserved), the size is adapted to the installation space in the driver area, and completely wraps the VCU and integrated instrument into the housing to form a shielded cavity; Internal fixing and insulation: 2-3mm thick conductive foam is pasted on the inside of the shielding shell. The VCU and integrated instrument are fixed inside the shielding shell by insulating brackets. The conductive foam fills the gap between the equipment and the shell to ensure a uniform electric field inside the shell and enhance the shielding effect. The preferred design also includes heat dissipation: louvered ventilation holes (50mm in diameter, 4-6 holes) are opened on the side of the shielding shell, and the openings are covered with metal dustproof mesh (1mm in diameter). This not only prevents external dust from entering, but also ensures that the heat generated by the VCU and integrated instruments during operation can be smoothly discharged, preventing the temperature from being too high and affecting performance. The physical shielding of the blades forms a tortuous channel, and the external magnetic field needs to be refracted multiple times before entering the shield. Each refraction will be attenuated due to the magnetic shunting effect of the blades, and the magnetic field strength entering the interior can be reduced by more than 80%. Furthermore, the blade spacing is controlled at 5-8mm, and the hole diameter (maximum gap between blades) does not exceed 10mm, further reducing the area directly exposed to the magnetic field and avoiding shielding gaps caused by large hole diameters.

[0024] Grounding design: The shielding shell is connected to the vehicle grounding post through a multi-strand copper grounding wire with a cross-sectional area of ​​not less than 6mm² (grounding resistance ≤1Ω). At the same time, the outer braided mesh of the composite shielding wire harness forms a grounding synergy with the chassis area shielding structure to ensure that interference signals are discharged without dead zones.

[0025] Further optimized, the chassis area shielding structure 3 provides shielding protection for the power electronic unit (PEU) 5, transmission control unit (TCU) 6, and battery pack 7 in the chassis area. It is connected to the driver area shielding structure via a composite shielded wiring harness, specifically including: PEU / TCU shielding unit: It is made of 0.8-1.2mm thick permalloy plate stamped into a semi-enclosed structure, with the size adapted to the shape of PEU / TCU, covering the core circuit parts of PEU and TCU, and reserving wire harness interface and heat dissipation holes. Battery pack shielding unit: A 0.5mm thick aluminum foil is pasted on the inside of the battery pack shell, and a small permalloy shielding cover is installed on the outside of the BMS circuit board inside the battery pack to form a double shielding of the shell and the local area to prevent magnetic field interference with BMS signal acquisition. Each sub-area shielding unit is fixed to the chassis frame by a metal bracket, and the units are connected by copper busbars to form a chassis shielding network; at the same time, the PEU / TCU shielding unit is connected to the driver area shielding structure through a composite shielded wire harness to realize the signal transmission and shielding coordination of the two area shielding structures. Grounding design: The chassis area shielding structure is connected to the vehicle body grounding post through multiple copper grounding wires, sharing the grounding network with the driver area shielding structure to ensure unified discharge of interference signals throughout the entire area.

[0026] This invention achieves full-scenario protection for the core components of the driver's area (VCU, integrated instrument cluster) to the core components of the chassis area (PEU, TCU, battery pack) and the connecting wiring harness through a combination of a composite shielded wiring harness structure, a driver's area shielded structure, and a chassis area shielded structure. This solves the problem of incomplete shielding coverage in traditional solutions. The shielding structures of the driver's area and the chassis area achieve shielding continuity, signal transmission, and grounding coordination through the composite shielded wiring harness, forming a full-area protection network. The composite shielded wiring harness blocks link interference, the shielding structures of the two areas attenuate local magnetic fields, and the shared grounding network ensures rapid discharge of interference signals. The composite shielded wiring harness features a high-permeability shielding layer in the middle and high-permeability materials (permalloy, low-carbon steel) in the driver / chassis area shielding structure. These materials are specifically designed for low-frequency, strong magnetic fields, attenuating the intensity of 1300-2000Gs low-frequency magnetic fields within core components to below 50Gs, far below the antimagnetic threshold of electronic components (typically 200Gs), fundamentally preventing functional failures caused by low-frequency, strong magnetic fields. All structures utilize mature materials and processes (such as permalloy stamping and tinned copper wire braiding), eliminating the need for large-scale modifications to the vehicle's existing architecture. The driver area shielding structure can be installed using unused space in the driver's compartment, and the chassis area shielding structure can be fixed to the existing frame using brackets. The composite shielded wiring harness can directly replace traditional wiring harnesses, with implementation costs increasing by only 18%-22% compared to traditional solutions, while reducing the failure rate in high-magnetic environments by over 85%, demonstrating a significant cost-performance advantage. Figure 2 The area marked 12 is the high magnetic field source region, used to place the drive motor, and 14 is the magnetic field lines.

[0027] The working principle of this invention is as follows: When a vehicle enters a high magnetic environment, the hardware system of this invention works in concert. The composite shielded wiring harness reflects high-frequency interference through its outer metal braided mesh and magnetically shunts and absorbs low-frequency strong magnetic fields through its middle high-permeability layer, effectively blocking external magnetic fields from inducing interference voltage and current in the conductors inside the wiring harness. The optimized layout of the controller significantly reduces the ambient magnetic field strength of core components such as the VCU and PEU. The local magnetic shield further attenuates the residual magnetic field that has reached the installation position, providing a final physical protection for the precision circuits inside the controller. Through the synergy of the above-mentioned wiring harness shielding and spatial layout shielding, the normal operation of the vehicle's central nervous system (controller) and neural pathways (wiring harness) is ensured in a high magnetic field environment. The core of this invention is to centrally arrange the core controller in a low magnetic field strength area after the magnetic field has attenuated, such as the low magnetic field area of ​​the chassis.

[0028] Although some embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, and all such changes and alterations should fall within the scope of the present invention.

Claims

1. An electromagnetic compatibility structure suitable for high magnetic field environments in pure electric heavy-duty trucks, characterized in that, It includes a composite shielded wiring harness structure, a driver's area shielded structure, and a chassis area shielded structure; the composite shielded wiring harness structure is used for shielding and protecting the high-voltage power wiring harness and the low-voltage signal wiring harness, the driver's area shielded structure is used for shielding and protecting the vehicle controller and integrated instrument, and the chassis area shielded structure is used for shielding and protecting the power electronics unit, the transmission controller, and the battery pack. The driver's area shielded structure and the chassis area shielded structure are connected by the composite shielded wiring harness structure.

2. The electromagnetic compatibility structure for high magnetic field environments of pure electric heavy-duty trucks according to claim 1, characterized in that, The composite shielded wire harness structure comprises, from the inside out, a conductor, an inner insulating sheath, a middle high-permeability shielding layer, and an outer metal braided mesh; the conductor is made of high-purity electrolytic copper; the inner insulating sheath is made of cross-linked polyethylene or polyvinyl chloride; the middle high-permeability shielding layer is made of permalloy foil or nanocrystalline tape; and the outer metal braided mesh is woven from tin-plated copper wire.

3. The electromagnetic compatibility structure for high magnetic field environments of pure electric heavy-duty trucks according to claim 2, characterized in that, The composite shielded wire harness structure is provided with a copper crimping ring at the connection end with the driver area shielding structure and the chassis area shielding structure; the outer metal braided mesh of the composite shielded wire harness structure and the middle high magnetic permeability shielding layer are folded together into the metal interface of the driver area shielding structure or the chassis area shielding structure, and are crimped and fixed by the crimping ring to form a 360° low impedance overlap.

4. The electromagnetic compatibility structure for high magnetic field environments of pure electric heavy-duty trucks according to claim 1, characterized in that, The driver area shielding structure includes a closed shielding shell, conductive foam, and an insulating bracket; the conductive foam is adhered to the inside of the shielding shell; the insulating bracket is fixed inside the shielding shell and is used to install the vehicle controller and integrated instrument.

5. The electromagnetic compatibility structure for high magnetic field environments of pure electric heavy-duty trucks according to claim 4, characterized in that, The driver area shielding structure also includes a multi-strand copper grounding wire; one end is connected to the shielding shell, and the other end is connected to the grounding post of the pure electric heavy truck body.

6. The electromagnetic compatibility structure for high magnetic field environments of pure electric heavy-duty trucks according to claim 1, characterized in that, The chassis area shielding structure includes a PEU shielding unit, a TCU shielding unit, a battery pack shielding unit, and a copper busbar; the PEU shielding unit and the TCU shielding unit are both semi-enclosed structures; the battery pack shielding unit includes an aluminum foil pasted on the inside of the battery pack shell and a permalloy shielding cover installed on the outside of the battery pack BMS circuit board; the copper busbar is used to connect the PEU shielding unit, the TCU shielding unit, and the battery pack shielding unit to form a chassis shielding network.

7. The electromagnetic compatibility structure for high magnetic field environments of pure electric heavy-duty trucks according to claim 6, characterized in that, The chassis area shielding structure is connected to the vehicle body grounding post via multiple copper grounding wires; the driver area shielding structure shares the vehicle body grounding post with the chassis area shielding structure.

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