Subsea power transmission cable modelling: Reactive power compensation and transient response studies

With the depletion of existing oil and gas reserves, there is an increasing demand for deep-water oil and gas production, which requires long distance power transmission and distribution to several subsea electrical loads. Subsea cables (power umbilicals) are one of the key components in subsea power transmission. Modelling of subsea cables is important to study their transient and steady-state behaviour. In this paper, the suitability of cable models such as Bergerons, frequency dependent and simple-models for transient study have been investigated and discussed. Simulation results comparing the performance of different cable models are presented. Models suitable for reactive power compensation study are also explored. Based on the specifications of the subsea cable a reactive power compensation study for two different cable lengths 50 km and 150 km is performed. Simulation results show that the HVAC transmission is not a preferred option for subsea applications, especially for long length (> 50 km) of the cable, hence HVDC transmission is a preferred choice for longer cable length (> 50 km).