Mitsubishi has pulled off a come-from-behind victory in a wind turbine patent case against General Electric (GE) in the U.S. International Trade Commission (ITC). 

In a Notice issued on January 8th, the ITC terminated its investigation of GE’s complaint and found Mitsubishi did not violate any claims of the three patents asserted by GE.

GE filed the complaint in March of 2008, accusing Mitsubishi of infringing on certain claims of U.S. Patent Nos. 5,083,039 (’039 Patent) and 6,921,985 (’985 Patent).  GE later amended the complaint to include U.S. Patent No. 7,321,221 (’221 Patent). 

The ‘039 Patent is entitled “Variable speed wind turbine” and is directed to a variable speed turbine that provides responsive control of the generator torque. 

The ‘985 Patent is entitled “Low voltage ride through for wind turbine generators” and is directed to a wind turbine that includes a blade pitch control system and a turbine controller coupled with the blade pitch control system. 

The ‘221 Patent is entitled “Method for operating a wind power plant and method for operating it” and is directed to improved methods for stabilizing the supply voltage to a wind turbine after voltage drops without jeopardizing the electrical components of the turbine.  

A more detailed discussion of the asserted patents can be found in my previous post on the federal court case between GE and Mitsubishi here.

The ITC decision to let Mitsubishi off the hook reversed an administrative law judge’s (ALJ) ruling in August of last year that Mitsubishi had violated the ‘039 and ‘985 Patents. 

Shortly after the ALJ decision, an ITC investigative attorney filed a petition with the ITC commissioners questioning certain infringement findings and raising concerns about whether GE met the domestic industry requirement of Section 337.

The Notice of Termination clears the way for Mitsubishi to assemble its imported turbine components and build a $100 million wind power plant in Fort Smith, Arkansas.