With the continuous development of automobile electronic control technology, the number of automobile electronic equipment has increased greatly, the working frequency has gradually improved, and the power has gradually increased, which makes the automobile working environment full of electromagnetic waves, leading toAutomotive wiring harnessThe problem of electromagnetic interference is becoming increasingly prominent, ranging from affecting the normal operation of electronic equipment to damaging the corresponding electrical components. Therefore, the electromagnetic compatibility performance of automotive electronic equipment has been paid more and more attention. At present, it is urgent to apply widely the electromagnetic improvement technology for automotive equipment.

The complexity and variability of the composition of electromagnetic energy in the driving environment of the automobile electronic equipment operating on a car with constantly changing driving environment means that the system is subject to a wide range of sources of electromagnetic disturbance. The car wiring harness is distributed throughout the whole vehicle, and is the main source of electromagnetic interference inside the car, and it itself is often subject to electromagnetic interference.

Therefore, how to deal with electromagnetic interference is particularly important for car harnesses:

1. Shielded disturbance source equipment and related vehicle wiring harness: the electronic control unit used in the main electronic control system of the car should be sealed with shielded housing.

2. Add automobile wire harness filter: for long wire harness, in order to reduce conduction and radiation disturbance, filter should be added to the wire harness. It is more convenient to connect appropriate ferrite magnetic ring.

3. Reasonably plan the car harness: arrange the harness so that the low-power sensitive circuit is close to the signal source, and the high-power disturbing circuit is close to the load. Separate the low-power circuit and high-power circuit as far as possible to reduce the induced disturbance and radiation disturbance between the harnesses.

4. Improve equipment grounding: excellent grounding arrangement and improved grounding connection can reduce high-frequency impedance. The grounding of car electronic equipment is mainly connected to the nearby car body and harness shielding layer.

5. Reduce the area of the car harness receiving the disturbance: the harness should be designed with the minimum length, minimum impedance and minimum loop area. It is better to use the power supply method with small loop area such as twisted pair. Increase the distance from the equipment to the disturbance source: under the condition that the disturbance equipment is fixed, change the installation position of sensitive components to increase the distance to the disturbance source.

6. In addition, the electromagnetic disturbance of the car system also comes from the outside of the car and the body. The outside of the car is the disturbance of the car when it experiences various external electromagnetic environments while driving. The body static disturbance is related to the car and the external environment.