DCT

3:10-cv-00276

General Electric Co v. Mitsubishi Heavy Industries Ltd

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Key Events
Amended Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 3:10-cv-00276, N.D. Tex., 05/17/2010
  • Venue Allegations: Venue is based on Defendants' business activities in the district, including the sale, distribution, and commissioning of accused wind turbines at the Goat Mountain wind farm, and Defendant MPSA maintaining a business office and registered agent in the district.
  • Core Dispute: Plaintiff alleges that Defendants’ 2.4MW variable speed wind turbines infringe patents related to a wind turbine’s structural base frame and its electrical control systems for managing grid faults.
  • Technical Context: The technology concerns utility-scale wind power generation, specifically addressing mechanical challenges in erecting massive turbines and electrical challenges in maintaining grid stability.
  • Key Procedural History: While not mentioned in the complaint, subsequent public records from the USPTO are critical for context. U.S. Patent No. 6,879,055, the subject of the first count, was subjected to an inter partes reexamination requested in 2011, which resulted in the cancellation of all claims (1-18) in 2013. U.S. Patent No. 7,629,705 has a complex post-filing history, including multiple reexaminations and a disclaimer, resulting in the cancellation or disclaimer of several claims (9-18) and the amendment of claim 7. Independent claim 1 of the '705 patent has survived multiple reexamination challenges.

Case Timeline

Date Event
2001-04-20 '055 Patent Priority Date
2005-04-12 '055 Patent Issue Date
2006-10-20 '705 Patent Priority Date
2009-12-08 '705 Patent Issue Date
2010-05-17 Complaint Filing Date

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 6,879,055 - Base Frame for Mounting the Shaft of the Rotor of a Wind Power Plant onto the Plant Tower (Issued Apr. 12, 2005)

The Invention Explained

  • Problem Addressed: The patent’s background describes that as wind turbines become more powerful, their components (like the machine housing or gondola) become larger and heavier, creating "a considerable problem in the erecting of wind power plants" related to transportation and on-site assembly ('055 Patent, col. 1:30-36).
  • The Patented Solution: The invention proposes a two-part base frame to solve this logistical problem. The frame is split into a "discrete upper part that carries the drive train" and a "discrete lower part that has an azimuthal drive device" ('055 Patent, Claim 1). These two pre-assembled sections can be transported and lifted to the top of the tower separately, where they are then joined together at a "connection point" ('055 Patent, Abstract; col. 2:40-51). This connection point is specifically designed with a larger dimension along the rotor axis to better handle the mechanical stresses introduced by the wind-driven rotor ('055 Patent, col. 1:65-2:3).
  • Technical Importance: This modular design approach sought to simplify the logistics and reduce the crane capacity needed for erecting increasingly large and powerful wind turbines ('055 Patent, col. 1:47-51).

Key Claims at a Glance

  • The complaint asserts infringement of "one or more claims" without specification (Compl. ¶10). Independent claim 1 is representative of the core invention.
  • Independent Claim 1 requires:
    • A base frame for a wind power plant's drive train, affixed to the tower to rotate azimuthally.
    • The frame is constructed from a "discrete upper part" carrying the drive train and a "discrete lower part" with the azimuthal drive.
    • The two parts are "attachably joined" at a connection point.
    • The connection point extends along a horizontal cross-section that has a "larger dimension in the direction of the rotor axis than in the direction perpendicular to that."

U.S. Patent No. 7,629,705 - Method and Apparatus for Operating Electrical Machines (Issued Dec. 8, 2009)

The Invention Explained

  • Problem Addressed: The patent identifies that wind turbines are susceptible to grid voltage fluctuations, including severe "low voltage transients" approaching zero volts, and that such events can be "deleterious to continuous operation" by forcing the turbine to disconnect from the grid ('705 Patent, col. 1:32-37).
  • The Patented Solution: The invention is a method and control system that enables a wind turbine to "ride through" severe grid faults without disconnecting. It specifically facilitates "zero voltage ride through (ZVRT)," where the machine remains electrically connected to the power system even when the grid voltage drops to "approximately zero volts for an undetermined period of time" ('705 Patent, Claim 1; Abstract). The patent describes achieving this using a phase-locked loop (PLL) regulator that operates in different states, dynamically switching between different sets of control parameters (gains and limits) depending on the severity of the grid disturbance ('705 Patent, col. 6:56-65; Figs. 5-6).
  • Technical Importance: This ZVRT capability is critical for maintaining overall power grid stability as the proportion of variable renewable energy sources like wind power increases, a need reflected in regulatory requirements ('705 Patent, col. 5:62-6:2).

Key Claims at a Glance

  • The complaint asserts infringement of "one or more claims" without specification (Compl. ¶16). Independent claims 1 (method) and 7 (system) are representative.
  • Independent Claim 1 requires:
    • A method of operating an electrical machine coupled to a power system.
    • "Configuring the electrical machine" to remain connected to the power system during and after a voltage amplitude operates outside a predetermined range.
    • This "configuring" includes coupling a control system to the power system and the machine.
    • The configuration enables the machine to remain connected even when the voltage decreases to "approximately zero volts," thereby facilitating "zero voltage ride through (ZVRT)."

III. The Accused Instrumentality

  • Product Identification: Defendants' 2.4MW variable speed wind turbine (Compl. ¶¶10, 16).
  • Functionality and Market Context:
    • The accused product is a utility-scale wind turbine sold for installation in large wind farm projects across the United States, including projects in Texas and Oregon (Compl. ¶¶11, 17).
    • The complaint alleges two key technical functionalities relevant to the patents. First, by implication, is the turbine's structural base frame design ('055 Patent allegations). Second, and more explicitly, is the turbine’s electrical control system, which allegedly provides the "ability to remain connected to the grid during certain faults on the transmission system, including certain voltage excursions down to zero volts" (Compl. ¶17). The complaint notes that Defendants have provided technical specifications to customers regarding this capability and the turbine's compliance with FERC Order 661a, a grid code relating to fault ride-through performance (Compl. ¶17).
    • No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint does not provide a claim chart or sufficient technical detail to construct a representative claim chart for either patent. The infringement theories are summarized below in prose.

  • ’055 Patent Infringement Theory: The complaint alleges that the physical construction of the accused 2.4MW turbine infringes one or more claims (Compl. ¶10). The infringement theory appears to be that the turbine’s base frame is a two-part, modular assembly—functionally equivalent to the claimed "discrete upper part" and "discrete lower part"—that is joined on-site and possesses a connection point with the geometry required by the claims (Compl. ¶¶10-12).
  • ’705 Patent Infringement Theory: The complaint alleges that the accused 2.4MW turbine’s method of operation and control system infringe one or more claims (Compl. ¶16). The core of this theory is that the accused turbines practice the claimed ZVRT method. This is supported by allegations that Defendants market the turbine as having the "ability to remain connected to the grid during... voltage excursions down to zero volts" and have provided customers with technical documentation describing these features (Compl. ¶17).
  • Identified Points of Contention:
    • '055 Patent: A primary factual question will be whether the accused turbine's base frame is constructed from "discrete" upper and lower parts that are "attachably joined" in the manner claimed, or if its structure differs materially. A further point of contention would involve the specific geometry of the connection point and whether it has a "larger dimension in the direction of the rotor axis" as required by claim 1.
    • '705 Patent: A central technical question will be whether the accused product’s control system performs the specific steps of the claimed method. The dispute may turn on whether simply remaining connected to the grid during a zero-volt event is sufficient for infringement, or if infringement requires using the specific kind of "configuring" and dynamic control logic detailed in the patent's specification.

V. Key Claim Terms for Construction

  • ’055 Patent - "a discrete upper part... and a discrete lower part" (from Claim 1)
    • Context and Importance: The definition of "discrete" parts is fundamental to the patent's modularity concept. Defendants could argue that their turbine's frame is a more integrated unit or that the functional components are divided in a way that does not map onto the claim's specific division (e.g., the drive train in the upper part and the azimuthal drive in the lower).
    • Intrinsic Evidence for a Broader Interpretation: The specification emphasizes the purpose of the two-part construction is to achieve "a division of the total mass and the total dimensions into two partial systems" to ease transport and lifting, suggesting a functional definition ('055 Patent, col. 1:44-48).
    • Intrinsic Evidence for a Narrower Interpretation: The detailed description and figures show a very specific embodiment of an upper part (6) and a lower part (16), which could be argued to limit the scope of these terms to structures that closely mirror this illustrated arrangement ('055 Patent, figs. 1-3).
  • ’705 Patent - "configuring the electrical machine and the control system" (from Claim 1)
    • Context and Importance: This active "configuring" step is what enables the patented ZVRT capability. The infringement analysis will depend heavily on whether this term is construed to mean the initial factory setup of the control logic or if it requires the specific dynamic, multi-state adjustment process detailed in the patent.
    • Intrinsic Evidence for a Broader Interpretation: A plaintiff might argue that providing a customer with a turbine pre-programmed with ZVRT logic constitutes "configuring" the system to perform the patented method, as the system is thereby set up to remain connected during a fault ('705 Patent, col. 2:51-57).
    • Intrinsic Evidence for a Narrower Interpretation: The specification provides a highly detailed description of a PLL state machine that switches between multiple states with different gain and limit values to manage grid faults ('705 Patent, col. 7:1-col. 10:65; Figs. 4-6). A defendant would likely argue this detailed disclosure limits the term "configuring" to this specific dynamic, multi-state control methodology.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges inducement and contributory infringement for both patents. It asserts that Defendants supply the 2.4MW turbines knowing they are "especially made or especially adapted for use in infringement" and not a staple article of commerce (Compl. ¶¶11, 17). Inducement is further alleged based on Defendants providing customers with documentation like "technical specifications, ... installation manuals, ... and operation and maintenance manuals" that describe and instruct on the use of the infringing features (Compl. ¶¶11, 17).
  • Willful Infringement: The complaint does not use the term "willful," but it requests a finding that the case is "exceptional" and an award of attorneys' fees pursuant to 35 U.S.C. § 285 (Compl. ¶23.F). The allegations supporting potential willfulness are based on infringing conduct occurring after the issuance dates of both patents (Compl. ¶¶11, 17).

VII. Analyst’s Conclusion: Key Questions for the Case

  1. A threshold issue for the first count is one of viability: given that all claims of the '055 patent were cancelled in a reexamination proceeding that concluded after the complaint was filed, what legal basis, if any, remains for the infringement allegations related to that patent?
  2. For the '705 patent, a key evidentiary question will be one of technical implementation: does the accused turbine's control system achieve zero-voltage ride-through using the dynamic, multi-state PLL regulator detailed in the patent's specification, or does it employ a technologically distinct method, raising the question of a fundamental mismatch in operation?
  3. The dispute over the '705 patent may also turn on a question of definitional scope: does the claim term "configuring," in the context of the patent's disclosure, broadly cover any pre-programming of a ZVRT capability, or is it limited to the specific, dynamic in-operation adjustment scheme that constitutes the patent's preferred embodiment?