by Philip Totaro, Principal, Totaro & Associates
The General Electric Company (GE) recently announced that it would take a 90% stake in Converteam for US$3.2B. Converteam’s core technology focus is on converters and grid interconnect equipment for solar and wind as well as permanent magnet generators / motors for wind turbines and propulsion systems.
While based in Europe, Converteam has 19 issued patents in the US and 18 pending applications which have published so far. As it relates to solar and wind, the largest portion of their portfolio deals with frequency and voltage regulation, and more specifically with active and reactive power control.
U.S. Patents Nos. 7,372,174, 7,511,385, 7,656,052, 7,692,321 and 7,755,209 all relate to a full power conversion system with a reactive power control approach utilizing a DC link demand signal as input to converter controller:It is interesting that long-time Siemens AG wind turbine technology thought leader, Henrik Stiesdal is listed as a co-inventor on these patents, highlighting the commercial relationships with Siemens for their 3MW direct drive wind turbine technology.
With a cross license arrangement on key generator, converter and controls technology between Siemens AG and Converteam, this deal now provides GE with access to IP rights which they may need to continue operating their own technology.
In addition, Converteam has their own flavor of a variable speed control patent with U.S. Patent No. 7,405,490 (‘490 Patent) in which adjustment of active power output from the generator is based on input from the DC to AC inverter which is connected to the power grid.
In light of the expiration of GE’s noteworthy and heavily litigated U.S. Patent No. 5,083,039 relating to variable speed control with an induction generator, the ‘490 Patent may be part of a suite of patents which helps GE protect the next generation of variable speed technology.
Converteam also has some patents relating to grid interconnection and generator technology. U.S. Patent No. 7,471,532 is directed to a more efficient converter which requires fewer parts than the previous generation of technology.
The move towards medium voltage on the power grid has been part of the emerging trends for the industry in the hopes of providing more efficient transmission of energy.
U.S. Patent No. 7,675,271 deals with generator technology which helps the generator ramp up from standstill. U.S. Patent No. 7,768,169, entitled “Magnet retaining arrangement,” and U.S. Patent No. 7,714,473, entitled “Electrical machines with reduced cogging,” both deal with permanent magnet generator technology which helps to enhance efficiency and improve reliability.
Converteam also recently announced that they are developing a superconducting generator, which they have termed HYDROGENIE for the hydro-power market. According to a February 21st press release (Converteam_Release) the company has successfully completed some basic testing of this technology and are moving towards full scale testing of a 1.7MW generator later this year.
The superconducting generator technology is likely to be the subject of numerous patents and is also highly likely to be leveraged into their other lines of business, such as wind generators and propulsion.
This acquisition is a notable example of the previously identified trend in the wind industry for “grid friendly” wind turbines which utilize permanent magnet synchronous generators as well as full power conversion with the ability to control power factor and provide VARs to the grid.
With the Converteam patent portfolio, GE has now added to their 300+ patents in the wind sector with key technology that further strengthens their position in these future technology areas.
Please visit www.totaro-associates.com/articles for more information and to obtain the firm’s full wind turbine patent landscape study results or to download an offline copy of the summary.