How to choose high voltage cables for new energy vehicles?

Key characteristics of high voltage wires for hybrid and electric vehicles include:

Rated voltage

The rated voltage of the wire is the AC/DC limited voltage value that the wire can withstand continuously without degrading the basic characteristics of the wire.

In the circuit of the battery system, the maximum rated voltage can reach DC 600V. When selecting the wire type, special attention should be paid to the manufacturer's regulations on the working voltage of the wire. The rated voltage of the wire should be greater than the maximum voltage of the loop.

Ampacity

The ampacity of the wire is the result of many factors working together. E.g:

• wire size

• wire material

• wire length

• Core resistivity

The ampacity and allowable temperature rise of the wire are closely related to the cross-sectional area of the wire specification.

Operating temperature

Conductor operating temperature can be divided into continuous operating temperature and maximum overload temperature. These temperatures can be measured by measuring the surface of the wire insulation.

continuous working temperature

Sustained temperature is the temperature at which the insulation layer of the wire withstands for 3000 hours (quoted from the ISO standard) without abnormalities. This temperature is obtained by measuring the surface of the wire insulation. The allowable steady-state (continuous) current results in a total wire temperature that is less than the continuous operating temperature. For continuous working conditions, the definition of the steady-state ampacity of the wire under a given ambient temperature condition refers to a specific current that the wire can sustain for 3000 hours without exceeding the continuous working temperature of the insulation.

Maximum overload temperature

The maximum overload temperature is based on the continuous working temperature of the wire insulation layer plus 60°C. The wire can withstand this temperature for up to an hour. The allowable overload current will cause the total wire temperature to be less than the overload operating temperature. Overload conditions may shorten the overall life of the wire, but do not cause damage to the wire.