Abstract: When a short-circuit fault occurs in the cable line, the mechanical properties of the cable bracket and hardware will be threatened under the action of short-circuit electric power. The traditional method of calculating cable short-circuit electric force is formula method. The formula method can only calculate the maximum short-circuit electric force, and there are limitations such as single solution object and inability to reflect the change of force with time. In this paper, the finite element calculation method based on electromagnetic coupling is used to establish the finite element calculation model of cable short-circuit electrodynamic force. Based on Maxwell 's electromagnetic theory and Gauss divergence theorem, the transient electromagnetic field analysis of the cable is carried out, and the change of short-circuit electrodynamic force on the cable with time is obtained. Compared with the calculation results of the formula method, there is only 2.11% error. The results show that the calculation method of short-circuit electrodynamic force based on finite element electromagnetic simulation can intuitively obtain the distribution and vibration frequency of electrodynamic force at each moment during short circuit. The electrodynamic calculation method of finite element electromagnetic simulation can be applied to short-circuit analysis of other fault types.

Key words: cable bracket, electrodynamic force, finite element method;three-phase short circuit;formula method