Magnetic Force Simulation of Cables in Microgrid during Faults

In recent years, more and more electric utilities are using underground cables to distribute electric power rather than overhead transmission line. However, the cost of installation and maintenance of underground cables is very expensive. Thus, the proper design and damage prediction of cables are crucial. This paper is focused on the magnetic force waveforms simulation of cables under different types of faults using PSCAD and COMSOL. The results show that three-phase fault leads to the largest magnetic forces and the maximum magnitude of the forces in the x-direction is about 2.5 N. Also, the magnetic fields surrounding the cables are different depending on the arrangements of cables buried method. Although the magnitude is small, considering the long distance and long operating time of underground cables, the forces between cables can cause failures under some conditions. In the future, more types of faults such as high impedance fault and different protecting technologies can be studied.