Doubly fed induction machine is a wound-rotor doubly fed electric machine and has advantages over a conventional induction machine in wind power applications
1. As the rotor circuit is controlled by a power electronics converter, the induction generator is able to both import and export reactive power allowing the machine to support the grid during severe voltage disturbances
2. Control of the rotor voltages and currents enables the induction machine to remain synchronized with the grid while the wind turbine speed varies
This report gives an overview of patenting activity around Doubly-fed Induction Generators (DFIG) used in the horizontal axis wind turbines for efficient power generation. Patents were categorized as per key DFIG technologies such as control circuits, operating modes, convertor types and protection circuits which were further classified as sub categories and analyzed for generating different trends within PatSeer Project.
DFIG or Doubly Fed Induction Generator technology has seen a steep increase in the number of patent publications in 2012 as wind energy installations increase globally.
Published: Feb 26, 2013