%0 Journal Article
%T Development of an Analytically Described Pitch Regulator for a Wind Turbine to Be Used for Grid Disturbance Studies
%A Pinar Tokat
%A Torbj£¿rn Thiringer
%A Peiyuan Chen
%J Journal of Energy
%D 2013
%R 10.1155/2013/203174
%X In this paper, a pitch controller for a variable-speed wind turbine to be used in the high wind speed region is derived. The pitch regulator parameters are determined using analytical expressions and are compared with numerical calculations. In order to derive the pitch regulated wind turbine model, blade element momentum theory is utilized and reformulated analytically. Appropriate simplifications are made and, finally, the analytically derived pitch regulated wind turbine model is tested under grid disturbances such as voltage dips and spinning reserve provision. From this work it was found that by linearizing the blade profiles, one can analytically derive a fully functioned pitch regulator. In spite of all nonlinearities, a single pitch controller setting which is valid for the whole operation region is shown to be sufficient. This system is tested under grid disturbances and it is proven that the system is capable of operating well during a 0% remaining voltage dip and also during the voltage recovery back to the rated voltage level. Accordingly, grid codes commonly referred to can be handled with this simply derived pitch regulator. Moreover, it is shown that the derived system works well for a spinning reserve application using a 90% spinning reserve ability and still maintains a robust turbine control. 1. Introduction Due to the increasing concern about the emissions caused by the usage of fossil fuels and the security issues regarding nuclear power, wind energy has nowadays become a popular source of electric power production. Wind energy is one of the fastest growing energy sources, which means that a great number of wind power plants have been installed and many more are to be installed further. Accordingly, the impact of wind energy units on the grid is of utmost importance to be studied. Many wind turbine studies require modeling and simulation of wind turbines. Today, most wind turbines are of the variable-speed type and pitching is an essential feature of the variable-speed operation. In [1], pitch controller is explained but not derived, and in [2] pitch regulator is derived using a fairly extensive procedure. In [3, 4], the pitch regulator is designed using complex control methods. However, a simple design of a pitch regulator based on an analytical wind turbine model is not found in the literature. Such a ¡°simple and analytically described¡± pitch regulator design would be useful while performing and in particular while comparing different studies. Motivated by the reasons above, the purpose of this paper is to provide a fully traceable
%U http://www.hindawi.com/journals/jen/2013/203174/