Abstrakt

CONTROL OF DOUBLY FED INDUCTION GENERATOR BASED WIND ENERGY CONVERSION SYSTEM

R.Rajeswari

Doubly-Fed Induction Generator (DFIG) based wind turbine with is gaining laurels in the growing wind market. By means of a bidirectional converter in the rotor circuit the DFIG is able to work as a generator in both sub-synchronous and super-synchronous modes. DFIG is connected with back-to-back converters. In general, VAR compensation is a major problem in WECS. Capacitors banks are to be added in parallel to the machine which leads to many problems such as over voltages etc. In this project, the grid side converter itself compensates for the reactive power rather than providing an additional compensating device. Additional power is also extracted from the rotor side. The machine-side converter controls the rotor speed by using the v/f control technique while the grid-side converter controls the dc-link voltage and ensures the operation by making the reactive power drawn by the system from the utility to zero by using the voltage-oriented control technique. The grid-side current is controlled by using reference current generation in p-q theory. The performance of DFIG is analyzed during the operation of sub-synchronous and super-synchronous generating modes using MATLAB/SIMULINK.