基于ANSYS的高压大截面电缆金具短路电动力和机械应力分析

ANSYS Based Analysis on Short-Circuit Force and Mechanical Stress of Cleats for High Voltage Large Cross-Sectional Cables

采用暂态短路电流计算方法和有限元法,分析了高压大截面电缆短路电动力的计算过程,推导出高压大截面电缆金具短路电动力的计算公式,同时考虑电缆蛇形敷设因素、导体外层介质缓冲作用及电缆位移偏转量,引入短路电动力工频分量(50 Hz)修正系数K1和两倍工频分量(100 Hz)修正系数K2对作用在电缆金具上的短路电动力进行修正。基于ANSYS建立电缆金具系统三维有限元计算模型,分别研究电缆敷设跨距和相间距对金具应力场的影响,并对双桥子-桃乡220 k V电缆段进行计算。由计算结果可知,在螺杆中点处产生的应力最大,即该位置最易变形或拉裂,对于220 k V电缆工程中"一"字形排列形式,电缆敷设跨距和相间距分别应满足l≤2.7 m,0.28 m≤a≤0.30 m。

Based on transient short-circuit current calculation methods and finite element method( FEM),the calculation process of the short-circuit forces for high voltage large-sectional cables is analyzed. And the shortcircuit forces calculation formula for cleats of high voltage large cross-sectional cable is gotten. Within the formula,the snake-like layout of the cable,the mediums cushion effect at the outer conductor,and the cable movement are taken into consideration. Moreover, the coefficients K1 and K2are introduced to modify the expression of the cable cleat force caused by 50 Hz and 100 Hz frequencies respectively. The 3D finite element calculation model of the cable cleat system is established based on ANSYS. Then the effect of span spacing and phase spacing on the cable cleats stress field has been studied. At the same time, the 220 k V power cable transmission line between Shuang Qiaozi and Tao Xiang has also been calculated. As can be seen from the simulation results,the maximum value of the stress is in the middle of the bolt. So it is most easy to deform or be pulled apart. The span and phase spacing should satisfy the standard l≤2. 7 m,0. 28 m≤a≤0. 30 m separately for 220 k V power cable transmission lines which are laid in parallel.