A Structured Wind Turbine Controller Evaluation Process Embedded into the V-Model for System Development

Controller design is always accompanied by an evaluation of control performance. However, for wind turbines, there is only a diffuse consensus on what a good controller constitutes, and no clear method to evaluate overall controller performance. Most evaluations, which can be found in wind turbine control literature, follow similar approaches. However, details, such as the models used, the scope of simulation or the result evaluation metric, can change the validity of results greatly. We sort these different evaluation approaches and align them with the V-Model for system design. This yields a structured process which defines requirements within three major domains: Stable automated operation, energy production and structural loads and limits. By following our proposed process, an impartial control evaluation scheme can be setup. Doing so, the complexity of evaluation and validation is handled in a systematic way. We give a clear indication which requirements need to be specified and show which difficulties arise when setting up an evaluating method. Furthermore, the influence of different evaluation parameters on the resulting controller quality measures is shown by evaluating results in slightly different ways. Thereby, the importance of the careful selection of quality measures is emphasized considering the high complexity of the task.