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. So we decided to search for patent filings on DFIG and analyze them using PatSeer.

Our search strategy included searching across patent content in multiple languages (both Latin and Non-Latin) and so words such as generador / alternador / 产生器 /  ジェネレータ / Jenerēta /  Erzeuger / Lichtmaschine / générateur / hatsudenki /  発電機  /  発生器 were some of the words we included for ‘generator’. (Detailed search strategy is present in the report below)

Some of the key insights that were derived as part of this activity are:

  • A lot of new filings are coming from China with US and Denmark being the traditional (and still active) patent filers.
  • Siemens continues to hold maximum number of unique inventions followed by GE and ABB.
  • Control Circuits for DFIG is a key focus area and Torque Control, Power Control and Speed control are some of sub-technologies that are seeing maximum filings from motor/generator manufacturers.

For more insights and to see the different charts we generated the full Report can be accessed here: PatSeer – Doubly Fed Induction Generator