Method for Determining the Upper Limit of Flow of High-Voltage DC Plastic Insulated Cable Accessories

Abstract

The present invention discloses a high -voltage DC plastic insulating cable attachment to the upper limit of the annex. This method includes steps: build a finite element model; calculate the maximum temperature difference between the maximum temperature and the maximum temperature difference between the insulation of different layers; The maximum allowable temperature difference between the inner and outer surfaces of each solid insulating layer is used as the constraint condition of the steady-state current-carrying capacity of the HVDC cable accessories, and the initial current-carrying interval is obtained; the idea of ​​dichotomy is used to continuously reduce the current-carrying interval, and finally the steady-state ampacity of the HVDC cable accessories is obtained ; During the operation of the high -voltage DC cable, the load calculation results are used as the access limit of the attachment. The present invention simultaneously considers the two constraint conditions of the maximum long-term allowable temperature of the conductive wire core and the maximum allowable temperature difference between the inner and outer surfaces of each solid insulating layer, and conforms to the insulation characteristics of the high-voltage DC cable accessories; it can flexibly adjust the carrying capacity of the accessories according to changes in the external environment, and make full use of The transmission capacity of the power cable line is improved, and the utilization rate of the cable is improved.

Description

technical field [0001] The invention relates to the field of electric power technology, in particular to a method for determining the upper limit of the current flow of high-voltage DC plastic insulated cable accessories (including terminals and joints). Background technique [0002] Accurate calculation of the steady-state current carrying capacity of HVDC cable accessories and the determination of the upper limit of the current flow are of great significance for the full utilization of its transmission capacity. [0003] At present, the method of determining the current carrying capacity of the cable body is mainly based on the analytical calculation method based on IEC 60287 and the numerical calculation method using boundary elements, finite differences, and finite elements. It can be seen that the research on the current-carrying capacity of the cable body has been perfected day by day, but there is still a lack of in-depth research on the relationship between the tempe...

AI Technical Summary

Problems solved by technology

It can be seen that the research on the current carrying capacity of the cable body has been gradually improved in the current stage, but there is still a lack of in-depth research on the relationship between the temperature distribution and the current carrying capacity of the cable accessories.

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