Basic principles for wiring harness layout of electric vehicles:

1. Harness layout architecture

The arrangement of automobile wiring harness generally includes H type, Y type, E type and Sichuan type. Generally speaking, if the high and low voltage are planned together, the Chuan-style layout is generally preferred, that is, the high voltage harness is in the middle and the low voltage harness is distributed on both sides to avoid problems caused by the EMC high and low voltage harness layout.

2. Vibration shock

The vibration and impact conditions of electric vehicle powertrain, layout space, NVH and other aspects are not good, so the wire harness arranged on the vibration source or powertrain must be fixed on the vibration body, and the clearance between the wire harness motion envelope and other parts is 25mm.

3. Waterproof and airtight - vehicle harness

Electric vehicles are sensitive to water and local standards are strict. Generally speaking, the part of the outdoor harness connector below the plane formed by the left and right longitudinal beams needs to reach IP69k, which can meet the waterproof requirements by adding the necessary shield cover or increasing the position of the connector.

4. Waterproof and airtight - power battery harness

The power battery pack shall adopt automobile grade plug-in, which shall be arranged at the rear or upper part of the battery pack. The wires shall be routed indoors or from the rear to achieve reliable waterproof performance and facilitate assembly and maintenance

5. Waterproof and airtight - indoor harness

The indoor wiring harness of the fuel car is basically fixed with holes. In order to completely solve the problem of water ingress into the wire harness fixing hole, all indoor wire harnesses of electric vehicles are fixed by direct welding bolts. Of course, some hollow sheet metal in the room can still be fixed with holes.

6. Electromagnetic interference

Compared with fuel vehicles, electric vehicles have stronger electromagnetic interference. In addition to reducing interference sources and improving anti-interference ability, reasonable arrangement of electromagnetic interference and interfered electrical components, and reasonable arrangement of wiring harness conduction path are also important methods to solve electromagnetic interference problems.

Take the car model with air conditioning reversing central control large screen mosaic as an example. The main reason is that in addition to the electrical components themselves, the selection and layout of harness are also important reasons. After overlapping and separating the parts of the harness, power line and video signal line, the image effect is significantly improved. In addition, the arrangement of grounding points is also an important factor affecting electromagnetic interference.

7. Temperature field factor

Compared with fuel vehicles, electric vehicles have better temperature field environment. It can be seen from the test data that there are electric boxes, drive motors and PEUs with high temperature in the front cabin. Since the maximum temperature point is not more than 60 ℃, as long as the cooling system is properly designed, the harness of the front cabin can be arranged in the wrong temperature field. Think too much.

8. New substrate wire technology changes the harness layout

The development and deployment of new substrate wire technologies such as optical fiber is an important development direction of lightweight vehicle harness system, and can optimize the changes of harness layout.