The difference between new energy vehicle high voltage cable and household cable


Deta:

2020-08-13

The structure of new energy vehicle high voltage cable is slightly different from that of household cable

The structure of new energy vehicle high voltage cable is slightly different from that of household cable
(1) The household cable is solid copper core, while the new energy vehicle high-voltage wire is composed of several thin copper wires. This will increase the conductivity. When there is alternating current or alternating magnetic field in the conductor, the "skin effect" will occur, and the current will be concentrated in the "skin part" of the conductor, and the current density on the surface of the conductor will be greater than the density of the center. Roughly speaking, it can be understood that the conductivity mainly depends on the conductive surface.
The higher the frequency of AC current, the more obvious the skin effect. Household electricity is 220 V, 50 Hz. The high-voltage platform of new energy vehicles is 300-400v, and the frequency can reach the level of kHz, dozens of times higher than that of household appliances. Therefore, it is necessary to reduce the "core" area of the high-voltage harness.
As an extreme example, assuming that the wire is infinitely thin, you can see that the entire wire is conducting, and can significantly improve the conductivity of the high voltage harness made up of these countless thin wires.
There are other advantages. The cross-sectional area of the main high-voltage wire harness is 50 mm?, which is 5-10 times of that of household electricity. It is more rigid and difficult to bend. This is not only difficult to arrange in the vehicle, but also may pierce the cockpit after the collision, which increases the potential safety hazard. Considering the strength, toughness and safety, new energy vehicle high-voltage cable is also a better choice.
(2) The high voltage harness of new energy vehicle has shielding layer
Maxwell said electricity creates magnetism. When the current flows through the wire, a magnetic field will be generated around the wire. The shielding layer can shield the electromagnetic field in the wiring harness without affecting other components and reducing electromagnetic radiation. It can also shield external influences and prevent interference from external magnetic field.
The basic principle of high-voltage wires for household electrical appliances and new energy vehicles is the same. They choose the right wires according to the current and voltage requirements. The thicker the wires are, the better. In addition, due to the higher requirements of service conditions, the wire manufacturer's new energy vehicle high-voltage wire standards are higher, and more details will be considered in the design, which is safer and more durable.