Cable current-carrying capacity calculation method based on finite element

Abstract

The invention discloses a cable current-carrying capacity calculation method based on a finite element. Finite element simulation software is used for modeling, and through calculating simulation cable thermal field distribution, current-carrying capacity of a corresponding cross-section cable under demand environmental conditions. The steps comprise: a, setting and / or selecting a required simulation model module; b, according to actual dimensions of a cable, establishing a simulation model; c, setting solution domains of the cable and the environment where the cable is located; d, setting a boundary condition; e, meshing; f, setting solution; g, solving and calculating whether temperature of a conductor reaches maximum allowable temperature in continuous working; h, if a conclusion of the step g is yes, simulation ending, current at the maximum allowable temperature being cable current-carrying capacity; if the conclusion is no, changing a current value of the conductor, repeating step e to step g, until the conclusion is yes. The method accurately responds state of cable current-carrying capacity, and provides foundation for design and research of cable laying.

Description

technical field [0001] The invention relates to the technical field of brushes, in particular to a method for calculating the ampacity of cables based on finite elements. Background technique [0002] Cable ampacity refers to the amount of current that a cable line passes when transmitting electric energy. Under thermal stability conditions, the cable ampacity when the cable conductor reaches the long-term allowable working temperature is called the long-term allowable ampacity of the cable. [0003] In the existing technology, the calculation mainstream is to use the calculation standard IEC 60287 of the International Electrotechnical Commission (IEC). The formula in can easily calculate the ampacity, but some algorithms are too cumbersome, and the calculation results are conservative. In addition, it only gives the calculation formula for the proximity effect of single-circuit cables, and in practice, multiple circuits are often laid in clusters. For the laying forms of ...

AI Technical Summary

Problems solved by technology

[0003] In the existing technology, the calculation mainstream is to use the calculation standard IEC 60287 of the International Electrotechnical Commission (IEC). The formula in can easily calculate the ampacity, but some algorithms are too cumbersome, and the calculation results are conservative

In addition, it only gives the calculation formula for the proximity effect of single-circuit cables, and in practice, multiple circuits are often laid in clusters

For the laying form of pipes and tunnel lights, the calculation formulas given in the standards are based on empirical summaries. In practice, there are couplings of heat conduction methods such as natural convection, heat radiation, and heat conduction. Simple empirical formulas will also have certain errors.

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