Heat Transfer Simulations for MVDC Power Cable Under Low Pressures

Power cable is an essential element of the future electric power system in commercial aircraft. One of the significant issues for MVDC cable operations under low-pressure applications is heat transfer. The purpose of this study is to increase the power delivery of the cable under these harsh conditions. The temperature field across the power cable depends on the velocity of airflow which is a function of ambient pressure and temperature, surface emissivity, and insulator and conductor conductivity. Insulator conductivity is also a function of electric field and temperature. As the temperature and the electric field increase, the conductivity of the dielectric increases which leads to the breakdown voltage even at lower voltages. Therefore, a coupled multi-physics study is conducted in COMSOL software to calculate the temperature and electric field across the cable. In this paper, the temperature and electric field across the 5 kV DC Southwire cable is studied as the pressure reduces from atmospheric pressure to 18.8 kPa. Consequently, the electric field across the insulation is calculated at different conductor currents.