System for monitoring the vibrations of a wind turbine

Abstract

A system for monitoring the vibrations, in particular the natural frequency, of a tower (1) of a wind turbine (2) is proposed, comprising vibration sensors (3) assigned to the tower (1) and an evaluation unit (4) for processing vibration sensor data. To enable reliable assessments of damage to the tower (1), it is proposed that several vibration sensors (3) be arranged in a ring around the tower axis (6) in three or more tower cross-sectional planes (5). The evaluation unit (4) records the vibration amplitudes (A) assigned to the respective tower cross-sectional planes (5) at observation times (Ti) and detects structural damage in the tower (1) by comparing the natural frequencies (fi) and the amplitude ratios (A) over an observation period.