Individual channel analysis of induction generator-based wind turbines

Abstract

Wind penetration into electricity grids has been significant over the last decades. The need of comprehensive studies to identify the interactions between wind farms with the power system has been recognised. In line with this, the individual channel analysis of induction generator-based wind turbines is presented in this paper. Individual channel analysis and design (ICAD) is a frequency domain framework with the help of which the investigation of the potential and limitations for control design of multivariable systems can be assessed. Under this framework, a formal evaluation of the internal coupling inherent to variable-speed wind turbines is carried out — with the coupling being quantified in the frequency domain through ICAD's multivariable structure function (MSF). Results offer formal insight into wind turbine control strategies based on vector control. Moreover, an appropriate analysis of the MSFs shows that the use of compensation loops may not be necessary to achieve a satisfactory control system design.