Invalidity dossier
US 8664800
System and method for distribution of inverter VAR support
Current assignee: GE Grid Solutions LLC
Added 9/20/2026, 5:23:45 AM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview: US8664800B2
Title: System and method for distribution of inverter VAR support
Patent number / application: US8664800B2; Application US12/872,577
Assignee (per source): Original assignee General Electric Co; current assignee listed as GE Grid Solutions LLC
Key dates (per source):
- Priority/filing date: 2010-08-31
- Publication of US20120049636A1: 2012-03-01
- Grant/publication of US8664800B2: 2014-03-04
- Anticipated expiration: 2030-08-31 (stated as an assumption)
Inventors named: Anthony William Galbraith, Owen Jannis Schelenz, Mark Edward Cardinal, Andreas Kirchner, Nicholas Wright Miller, Kara Clark
Purpose and plain-language scope (from the supplied text):
The invention generally relates to renewable energy sources, and more particularly to systems and methods for controlling power in renewable energy sources. Because variable renewable generation (solar, wind, hydro) can be unstable—for example, solar output varying with cloud coverage and sun position—the patent addresses coordinating reactive power (VAR) support from power inverters.
One described embodiment is a power inverter system with one or more power inverters receiving power from at least one energy source, and at least one controller that controls each inverter via algorithmic software reactive power support commands, such that an inverter provides reactive power to a grid based on its reactive power capacity and only while its total power capacity is not exhausted in generating real power. A corresponding method embodiment is also described.
In the illustrated solar farm example, a central controller continuously polls inverters to determine present real and reactive power capacity. Upon receiving a VAR command via a grid feedback link, it requests VAR support only from inverters with sufficient reserve capacity, in proportion to each inverter's available VAR capacity—so an inverter already at maximum real power output is not requested to supply VARs. This avoids curtailing inverters with higher real power production.
Source: https://patents.google.com/patent/[US8664800](/patent/US8664800)/en
What the excerpt does not establish: It does not provide the full claims, complete description, or drawings. It does not verify inventorship, claim scope, legal status, enforceability, or the accuracy of assignee/expiration listings. It briefly mentions a possible distributed control architecture but the excerpt is truncated. Litigation, ownership transfers, validity, and prior art were not researched.
Generated 10/1/2026, 10:02:43 PM
Cases on file (0)
Specific litigation cases in our database that name US patent 8664800. The free-form analysis below may also discuss cases beyond this list.
No cases on file mention this patent. Upload a CSV or add a case manually in Admin → Manage litigation cases.
Litigation summary
Past and pending lawsuits — plaintiffs, defendants, jurisdictions, outcomes, and notable rulings.
Proceedings on file (0)
All PTAB activity →AIA trial proceedings (IPR / PGR / CBM) filed at the USPTO Patent Trial and Appeal Board against this patent. Sourced from the USPTO Open Data Portal and refreshed every six hours; each proceeding number deep-links to the PTAB E2E docket.
No PTAB proceedings on file. This patent has not been challenged via IPR, PGR, or CBM. The absence is itself a signal — well-asserted patents eventually attract IPRs. The LLM analysis below may surface filings the ODP feed hasn’t indexed yet.
PTAB challenges
AIA trial proceedings at the USPTO Patent Trial and Appeal Board — IPR, PGR, and CBM. Petitioners, judge panels, claim-level invalidation outcomes from Final Written Decisions, and Federal Circuit appeals. The single most important defensive datapoint after litigation history.
Assignment history
Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.
Prior art
Earlier patents, publications, and products that may anticipate or render the claims unpatentable.
Obviousness
Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.
Extensions
Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.
Derivative works
Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.