AN OFFSHORE WIND TURBINE WITH LIQUID-COOLING

摘要

An offshore wind turbine is disclosed wherein the power transmission in the nacelle is cooled by means of a liquid conducted to the nacelle from the tower on which the nacelle is pivotally arranged around a vertical yawing axis. The liquid transfers heat to the seawater near the turbine which is used as a heat sink of low temperature and enormous heat capacity as compared to traditional air cooling. The liquid is conducted in a closed circuit and the cooling system may comprise more than one cooling circuit. The flow of cooling-liquid may be conducted between the tower and the nacelle through a heat transfer unit having a first part that is stationary with respect to the tower and a second part that is stationary with respect to the nacelle. The parts have at least one annular passageway for a liquid flow defined between abutting surfaces of the parts.