Finite Element Analysis of Thermomechanical Performance of High Voltage Cable under Bending

Bending has a major impact on the operation and life of high voltage cables. In order to obtain the influence of cable thermal expansion on cable internal stress under different bending radii, some thermomechanical coupling finite element models of 220kV high voltage cable bending are established. Set the cable to work under the rated current load, the conductor temperature reaches the maximum allowable operating temperature of 90 °C. Solve the thermomechanical element model with bending radius of 15 times, 20 times, 25 times, 30 times, 35 times, 40 times, 45 times and 50 times of the outer diameter of the cable. The results show that the stress and strain in the middle part of the copper conductor and the aluminum sheath are the largest, and the intermediate ends are gradually reduced. The stress and strain of the insulating layer, the semi-conductive water layer and the middle portion of the outer layer are the smallest, and gradually increase from the middle to the both sides. The maximum displacement and bending radius produced by thermal expansion of the cable are linear; The maximum cable stress and strain decrease with increasing bending radius and are in a power function relationship. This study can provide theoretical and data support for cable bending facilities and state prediction.