With the rapid development of the global new energy vehicle industry, high-voltage wiring harnesses, as the "major arteries" for energy transmission in electric vehicles, their processing quality directly affects the safety and reliability of the entire vehicle. Compared with the low-voltage wiring harnesses of traditional fuel vehicles, the high-voltage wiring harnesses of new energy vehicles need to withstand working voltages of 300V to 800V and large currents of over 200A, which puts forward higher requirements for material selection, production processes and quality control.

 

As a professional automotive wiring harness manufacturer, Aichie Tach Manufacturing has supply high-voltage cable assemblies solutions for over 30 new energy wiring harness customers. Its products have passed international certifications such as IATF16949/UL/CE/TUV.

 

 

I. Selection of Core Materials for High-Voltage Wiring Harnesses

Conductor material: Multi-strand twisted copper wire (cross-sectional area 16mm²-150mm²) is adopted, with tin plating to enhance oxidation resistance. Silver-plated copper wire is used in special scenarios to reduce contact resistance

2. Insulating materials: Cross-linked polyethylene (XLPE), silicone rubber or polytetrafluoroethylene (PTFE), with a temperature resistance grade of 150℃-200℃

3. Shielding layer: Double-layer shielding structure (aluminum foil + braided copper mesh), with a shielding coverage rate of ≥85%, effectively suppressing electromagnetic interference

4. Sheath material: Flame-retardant TPE or TPU material, which has passed UL94 V-0 flame-retardant certification, and the wear resistance coefficient needs to meet the industry standard

 

II. Wiring harness design Verification Stage

1. 3D wiring simulation: Utilize CATIA software to simulate the layout of the entire vehicle wiring harness, avoiding mechanical interference and electrical performance calculation in heat source areas: Accurately calculate voltage drop (≤3%), temperature rise (ΔT≤40℃), and current-carrying capacity margin

2. EMC simulation test: Predict the electromagnetic radiation value through CST software and optimize the shielding layer structure

3. Sample environmental testing: Conduct a 2000-hour salt spray test, 3,000 plug-and-pull tests, and a temperature shock test ranging from -40 ° C to 150 ° C

 

III. Core Processing Technology Flow

(1) Cable pretreatment

1. Automatic wire cutting: A servo-driven wire cutting machine is adopted, with the precision controlled within ±1mm. The cut surface should be smooth and free of burrs

2. Laser marking: Use ultraviolet laser to engrave line numbers, specifications and other information on the surface of the sheath, with a depth of 0.15-0.3mm

3. Terminal crimping: Completed by a fully automatic crimping machine, with a crimping height tolerance of ±0.02mm. The metallographic analysis of the profile must meet the VW60330 standard

4. Shielding treatment: Double-layer shielding layers are treated separately, with 360° aluminum foil covering and copper mesh braided density ≥90%

(II) Component Assembly

Injection molding: A vertical injection molding machine is used, with the mold temperature controlled at 80±5℃. The holding time is set according to the thickness of the material

2. Waterproof treatment: A double sealing structure (rubber gasket + potting compound) is adopted, with a protection level reaching IP67/ IP6K-9K

3. Assembly of high-voltage connectors: The pneumatic crimping equipment applies a torque of 50-80N·m, and the contact resistance is less than 0.5mΩ

4. Wire harness binding: High-temperature resistant cable ties are fixed at intervals of 150-200mm, with a bending radius of no less than 5 times the wire diameter

(3) Process Inspection

1. Online high-voltage testing: 2000V DC withstand voltage test (leakage current < 1mA/min), 1500V insulation resistance test

2. Conduction test: The micro-resistance tester detects the circuit impedance, with a deviation value of no more than 5%

3. Mechanical property test: Maintain a tensile force of 35kg for 1 minute, and the terminal displacement should be less than 0.2mm

4. Air tightness test: 3kPa air pressure test, leakage < 5mL/min

 

 

IV. Breakthroughs in Key Technologies of the industry

Lightweight technology: Aluminum wires are used to replace copper wires, reducing weight by 30% while maintaining electrical conductivity

2. Modular design: Develop integrated high-voltage distribution boxes to reduce connection nodes by more than 50%

3. Automated production: The introduction of six-axis robots enables automatic wiring, increasing efficiency by 40%

4. Intelligent detection System: By applying machine vision and AI algorithms, the defect detection rate has been increased to 99.8%

 

V. Key Points of Quality Control

1. Cleanliness management: The production environment maintains the ISO 14644-1 Class 8 cleanliness standard

2. Traceability System: Establish an MES production traceability system, with key parameters retained for at least 10 years

3. Process capability index: Critical dimensions CPK≥1.67, electrical characteristics CPK≥1.33

4. Aging test: 100% of the products undergo a 72-hour live aging test

 

 

VI. Industry Development Trends

Voltage platform upgrade: Develop new materials capable of withstanding 1000V for 800V high-voltage systems

2. Integrated development: Integrate fuses and current sensors into the wiring harness assembly

3. Application of liquid cooling technology: Development of integrated high-voltage wiring harnesses with cooling pipelines

4. Sustainable manufacturing: Establish a copper material recycling system, and increase the material utilization rate to 98%

 

The processing of high-voltage wiring harnesses for new energy vehicles is a deep integration of precision manufacturing and intelligent technology. From conductor selection to assembly testing, each link needs to strictly follow standards and specifications such as IEC 62196 and GB/T 18487. With the increase of voltage platforms and the development of intelligent driving, high-voltage wiring harnesses will evolve towards high integration and intelligence in the future. Aichie will continue to improve its process technology and establish a full life cycle quality management system to provide reliable guarantees for the safe operation of new energy vehicles.

Automotive high-voltage wiring harnesses are a type of cable system that has gradually become a key element along with the popularization of automotive technology, especially electric and hybrid vehicles. The following is a detailed introduction to automotive high-voltage wiring harnesses:

 

I. Definition and Function of HV Cable Harness

High-voltage wiring harnesses refer to cable systems used for transmitting high-voltage power signals and are mainly applied in electric vehicles and hybrid vehicles. These wiring harnesses are usually connected to batteries, inverters and motors to ensure the efficient transmission of electrical energy.

 

II. HV EV Cable Assembly Composition

High-voltage wiring harnesses are usually composed of the following parts:

1. Conductor: It is usually made of copper or aluminium and has good electrical conductivity.

2. Insulation layer: The key to preventing current leakage and short circuits. Insulating materials are usually cross-linked polyethylene (XLPE) or fluoroplastics, which can withstand high temperatures, are wear-resistant and have excellent electrical insulation properties.

3. Sheath: The outer protective layer of high-voltage wiring harnesses is usually made of materials that are resistant to high temperatures, oil and chemical corrosion.

4. Connector: It is used to connect the wiring harness with devices such as batteries and inverters. High-voltage connectors need to have excellent waterproof, dustproof and shockproof capabilities to adapt to the complex automotive working environment.

 

III. Characteristics and Requirements

1. Security

The design and manufacture of high-voltage wiring harnesses are directly related to the safety of automobiles. As high-voltage wiring harnesses carry the electrical energy of electric vehicles, once a fault occurs, it may lead to serious consequences such as short circuits and fires. Therefore, strict production standards and inspection procedures are important guarantees for ensuring the safety of high-voltage wiring harnesses.

2. Performance

The performance of high-voltage wiring harnesses affects the overall performance of a vehicle. For instance, the resistance and conductivity of the wiring harness directly affect the efficiency of current transmission, thereby influencing the power output and endurance of the motor. High-quality high-voltage wiring harnesses can effectively reduce energy loss and enhance the overall performance of electric vehicles.

3. Durability

High-voltage wiring harnesses need to withstand various complex environmental conditions throughout the life cycle of a vehicle, such as high temperature, low temperature, humidity, and vibration. Therefore, the material selection and manufacturing process of the wiring harness must have good durability. Durable high-voltage wiring harnesses can reduce maintenance frequency, lower usage costs and enhance consumer satisfaction.

 

IV. Classification and Layout

1. In new energy vehicles (taking pure electric as an example), high-voltage wiring harnesses can be divided into the following five major parts:

• High-voltage cables for power batteries
• The wiring harness connecting the power battery to the high-voltage box

2. Motor controller cable

The wiring harness connecting the high-voltage box to the motor controller

3. Fast charging wiring harness

The wiring harness connecting the fast charging port to the high-voltage box

4. Slow charging wiring harness

The wiring harness connecting the slow charging port to the on-board charger.

5. High-voltage accessory wiring harness (High-voltage wiring harness assembly)

The wiring harness connecting the high-voltage box to the DC/DC, on-board charger, air conditioning compressor and air conditioning PTC

 

The layout of high-voltage wiring harnesses for electric vehicles should follow the principle of proximity to minimize the use of high-voltage cables while meeting the requirements of the overall layout and high-voltage electrical design. In addition, it is necessary to pay attention to avoiding potential safety hazards such as electromagnetic interference, leakage of electricity and fire.

 

V. Notes

1. The layout of high-voltage wiring harnesses needs to comply with a series of safety requirements, such as visual concealment, compliance with safety collision regulations, consideration of ergonomics and ease of maintenance, etc

2. When arranging high-voltage wiring harnesses, it is essential to ensure that drivers, passengers or maintenance personnel cannot directly access the high-voltage wiring harnesses

3. When arranging high-voltage wiring harnesses, special attention should also be paid to avoiding areas with excessive squeezing and vibration amplitudes

 

In conclusion, automotive high-voltage wiring harnesses are an important component of electric vehicles and hybrid vehicles. Their safety, performance and durability are directly related to the overall performance and service life of the vehicle. Therefore, during the design and manufacturing process, it is necessary to strictly follow relevant standards and procedures to ensure the quality and reliability of high-voltage wiring harnesses.

Commercial vehicle high voltage cable assembly