Spectral Analysis of a Transmission System based on AC Submarine Cables for an Offshore Wind Farm

In this paper, a detailed spectral analysis of an offshore wind farm, based on AC submarine cables is carried out. It is well known that due to the capacitive character of the AC submarine cables, it is very common to find resonance problems in the transmitted power, associated to this issue. For that reason, this paper first analyzes which is the proper "pi" electric equivalent circuit to model the AC submarine cable in a given frequency range. Then, a detailed model and a spectral analysis of the entire transmission system is developed, deriving how factors such as submarine cable parameters, static reactive compensation, etc... affect to the amplitude and location of the resonances of the system. After that, a solution to mitigate the negative effect of these resonances is proposed, based on a passive filter design procedure. Finally, simulation results validate the performance of the offshore wind park under the proposed approach.