Invalidity dossier
US 7492060
Fault-tolerant circuit device in fuel cell AC inverter
Current assignee: Institute of Nuclear Energy Research
Added 9/23/2026, 10:31:53 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 7,492,060 B2
Title: Fault-tolerant circuit device in fuel cell AC inverter
Patent number / application: US 7,492,060 B2; application US 11/514,344; earlier publication US 2008/0054726 A1.
Assignee: Institute of Nuclear Energy Research (per the record, assigned to Atomic Energy Council – Institute of Nuclear Energy Research). Inventors: Yung-Ruei Chang, Yuan-Hsiang Ho, Chen-Min Chan.
Dates (as listed): Priority/filing date 2006-09-01; publication of the application 2008-03-06; granted 2009-02-17; status listed as expired – fee related, with an adjusted expiration noted as 2027-07-23.
Purpose: To keep a fuel cell AC inverter functioning when one of its inverter units malfunctions, by replacing the failed unit with a backup inverter unit, so the whole inverter continues operating.
Plain-language scope: The device comprises (a) multiple inverter units, each with a capacitor and several switch diodes, connected in series; (b) a dispatching and time-series control system connected to those inverter units and to multiple fuel cells; (c) multiple backup inverter units, each with a capacitor and switch diodes, connected to the control system and connected in series with the inverter units; (d) a control unit connected to the dispatching/time-series control system; (e) a detection unit connected to the inverter units, the backup units, and the control unit; and (f) a switch unit likewise connected, having switch components placed between the switch unit and each inverter unit and each backup unit. The description states that the switch unit opens the connection to a working inverter unit and shorts the connection to a backup unit, and reverses those states when a unit fails, substituting the backup. The process includes comparing each inverter unit's output voltage with a default value, searching for a backup unit, and reconnecting a backup unit to the corresponding fuel cell as needed. Inverter and backup units may be three-phase wye- or delta-connected. The cited prior art, U.S. RE37,126 E, uses series-connected inverter circuits with switch diodes and a capacitor.
What the excerpt does not establish: The excerpt omits portions of the detailed description (including steps (a), (b), (c), (f1), (g1), (g2), (h), and the full claims text); it provides no claim set, no figures, no litigation or ownership-transfer analysis, and no independent verification of dates or legal status, which the source itself labels as assumptions.
Generated 10/1/2026, 9:33:18 PM
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Prior art
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