Implementation of 132 kV for inner-array systems in offshore wind farms
I. Arrambide Department of Electrical Engineering, Escuela de Ingeniería de Guipúzcoa, University of the Basque Country, Donostia-San Sebastián (Spain) 2026-06-27

Abstract

Since offshore wind energy production is taking part in different countries´ energy mixes, significant cost reductions have been developed during last years. Together with offshore wind turbine power size one of the key improvements is stepping up inner-array system rated voltage from 33 kV to 66 kV or even to 132 kV expected for the beginning of the next decade. As the offshore wind turbines that currently range between 16~20 MW are being installed and up to 26 MW have been announced recently, the increase of voltage is a need in order to make more efficient collector system and to cut down costs, consequently, reducing the levelized cost of energy.

This work presents an inner-array power losses analysis, as well as, covers and compares current collector system voltage at 66 kV with the new expected 132 kV voltage level. Losses distribution is calculated according to IEC 60287 international standard. The results show that the energy losses are reduced if compare to actually 66 kV voltage.

Key words: Array system, offshore wind farm, energy losses, 132 kV

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