Research on Optimization Design of Cable Joint for Improving Cable Reliability

With the development of new energy technology, the reliability of direct burial cable joints plays an important role in power quality. The traditional hexagonal surround pressure connection method is prone to faults. A study of the failure mechanism is made through the site investigation and COMSOL simulation, then a new type of cable joint connection is designed. Comparing the two connection methods, the hexagonal surround pressure connection method is electrically and mechanically connected only by crimp tubes. It is apt to heat deformation. Under the same current excitation, the new connection method reduces the maximum current density by 82.6%, the maximum temperature rise by 60.3%, and the maximum thermal deformation by 82.8%. The effect of the dimensions of the new connection on the electric field, temperature and deformation is quantitatively analyzed. The results show that the electric field distribution and the deformation variable distribution at the connection position are jointly determined by the contact and the connecting tube, whereas the electric field distribution is mainly determined by the contact.