On-Load Tap Changer And Method For Operating An On-Load Tap Changer
Patent No. EP4404228 (titled "On-Load Tap Changer And Method For Operating An On-Load Tap Changer") was filed by Hitachi Energy on Jan 23, 2023. The application was issued on Aug 27, 2025.
Patent Summary
An on-load tap changer for voltage regulation in transformers or reactors comprises a first tap selector connected to a first tapped winding and a second tap selector connected to a second tapped winding. A first and second diverter switch connect to their respective tap selectors and to each other, arranging the tapped windings in series. The device further includes a first and second change-over selector for connection to the first and second tapped windings, respectively, enabling plus/minus regulation. To prevent change-over selectors from being exposed to excessive capacitive voltages when tapped windings are galvanically disconnected during operation, one or more high-ohmic resistances are integrated into the electrical connection between at least one diverter switch and at least one tapped winding.
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Date
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EP4404228
- Application Number
- EP23152906A
- Filing Date
- Jan 23, 2023
- Status
- Granted And Under Opposition
- Jul 25, 2025
- Publication Date
- Aug 27, 2025
- External Links
- Slate, Register , Google Patents