Computer simulation and analysis of electric and temperature fields of HVDC cables

HVDC cables play a more and more important role in interconnecting national grids and HVDC flexible power system. This paper deals with the calculation of electric and temperature fields in HVDC cables. The calculation of electric and temperature in an HVDC cables is far more complex than the equivalent case in AC cables. This is due to the fact that the conductivity of the cable insulation materials is temperature and field dependent, due to this fact that electric fields under dc voltage may be time-dependent. The field distribution in an HVDC cable may be of a capacitive or resistive nature. Electric field distribution is also influenced by temperature field. This even may lead to an instability that causes breakdown of the cable. The calculation and analysis of the temperature field distribution and its influence on the electric fields is carried out.