Vestas says it will challenge GE’s claims in lawsuit filed over wind turbine patent

On Monday, July 31st, Boston, MA-based global digital industrial firm General Electric (NYSE:GE) filed a complaint for patent infringement against Denmark-based wind turbine company Vestas Wind Systems A/S (CPH:VWS). GE filed the lawsuit in response to alleged infringement conducted by Vestas in the field of power grid technology. The suit is filed in the Central District of California.

GE is asserting one patent in the case: U.S. Patent No. 7629705, titled Method and Apparatus for Operating Electrical Machines. Issued in December 2009, it discloses a method for operating an electrical machine by coupling an electrical machine to an electric power system, and configuring the machine so that it remains electrically connected to the power system during and after any instances in which the operating voltage of the power system is outside of a predetermined range for an undetermined period of time. The resulting invention addresses issues regarding grid voltage fluctuations which can cause operating issues in wind turbine generators.

According to GE’s complaint, the ‘705 patent covers what is known as zero voltage ride through (ZVRT) technology. “Power grids naturally experience short-term voltage dips due to, for example, large electrical loads, lightning strikes, or short circuits,” GE’s complaint reads. “To avoid damage resulting from this voltage drop, wind turbines traditionally were designed to disconnect from the grid and attempt to reconnect after a certain period of time.” The technology patented by GE allows a turbine to remain connected to the grid even when the voltage drops to approximately zero. GE alleges that Central California is the proper venue due to Vestas A/S’ business operations within the district, including the San Gorgonio Wind Farm and Brookfiled Wind Farm. As well, GE alleges that Vestas-American, a U.S. subsidiary of Vestas A/S, is incorporated in the state of California.

GE contends that the ‘705 patent is valid in light of multiple reexaminations of the patent at the U.S. Patent and Trademark Office. Multiple exhibits attached to GE’s complaint show how the patent was subject to both ex parte and inter partes validity challenges petitioned by Japanese engineering giant Mitsubishi Heavy Industries (TYO:7011), petitions filed after GE asserted the ‘705 patent against Mitsubishi in February 2010. The patentability of claims 1, 7 and 8 of the ‘705 patent were upheld and GE ended up winning a $170 million damages award in the Northern District of Texas; GE alleges that it entered into a December 2013 settlement agreement with Mitsubishi regarding all legal activities between the two companies.

A series of Vestas wind turbines are identified as products infringing upon the ‘705 patent, including the V90-3.0 MW, V100-2.0 and V117-3.3 wind turbines. GE’s complaint includes excerpts from wind turbine brochures disseminated by Vestas which, according to GE’s allegations, shows how the accused wind turbines infringe upon at least claim 1 of the ‘705 patent, including the following language on fault ride-through technology:

“Vestas products, such as the V100-1.8 MW, are designed so that your wind park will be fully compliant with applicable grid codes at the point of common coupling. How this is achieved may differ from country to country, but generally, the Vestas advanced grid compliance system provides active and reactive power regulation, frequency regulation and fault ride-through capabilities to support grid levels and stability in the event of grid disturbances.”

GE further alleges that Vestas A/S had knowledge of the ‘705 patent going back to September 2011 when Vestas’ U.S. subsidiary and an engineer were served with subpoenas to provide evidence and testimony in GE’s case against Mitsubishi. For Vestas A/S’ part, the Danish company looks very willing to enter into a legal dispute with GE over the ‘705 patent. A Reuters brief published on August 2nd reports official statements from Vestas on the recent GE lawsuit. The comments reflect the fact that Vestas is aware of the suit and that the company intends to challenge the complaint, which Vestas feels is without merit.

Coverage on the GE patent suit against Vestas published by Bloomberg indicates that the suit comes at a time when the wind energy industry seems to be poised for growth. The business news outlet reports that, at the end of June, more than 25.8 gigawatts worth of wind farms were under construction, an increase of 41 percent over the same figure from the previous year. The legal dispute could easily become an international one as Bloomberg reports that installed wind turbines in 33 countries across six continents last year.

UPDATED August 8, 2017 at 11:26am. An earlier version of this article incorrectly identified Vestas as a Dutch company.