A VARIABLE-STRUCTURE STABILIZER FOR WIND TURBINE GENERATORS

A variable-structure stabilizer for improving the dynamic stability of a wind turbine generator supplying an infinite bus through a transmis sion line under widely varying loading conditions is presented. A stat e space formulation of the linearized system model is developed and us ed in the design of the stabilizer. The inputs to the stabilizer are r estricted to accessible states which renders its implementation practi cal. Digital simulation of the dynamic responses following pseudo-typi cal wind gusts for a conventional power system stabilizer and the prop osed variable-structure stabilizer are included for comparative purpos es. Whereas a conventional stabilizer design is based only on a partic ular operating point and its performance at other operating points is of necessity a compromise, it is shown that the main feature of the va riable-structure stabilizer is its ability to maintain improved dynami c performance as operating conditions change.