Understanding Wind Power Technology: Theory, Deployment and Optimisation

9Control of Wind Energy Systems

Reiner Johannes Schütt

Wind turbines (WTs), or several WTs gathered in a wind farm (WF), are complex systems whose operation requires extensive control of the overall system as well as of the subsystems. In this it is expected that wind turbine systems (WTSs) fulfil at least the requirements of conventional power stations with regards to reliability, efficiency and operational management. In contrast to conventional power stations, the supply of energy cannot be influenced but varies very strongly and quickly due to the wind speed. For independent and secure operation and the extensive adaption of the operation of WTSs for different application conditions, it is necessary to have a complex control technology that distributes the tasks to different subsystems.

Modern WTSs supply the electrical grid at the medium or high-voltage level by means of transformers. In order to optimise the feed-in power and to limit this to the rated power, WTs are used with and without gear drives, full power or part converters with variable speeds, and variable blade angles. The automation of WTSs includes the measurement, control, automation and monitoring of important characteristics within the WT as well as the WT and WF operational management. It includes remote monitoring and visualisation and the information and communication linkages to other systems, and here especially the integration into the primary grid management systems. The automations for this consist of ...