{"schemaVersion":1,"slug":"dynamic-voltage-restorer","name":"Dynamic voltage restorer","kind":"symbol","abbreviation":"DVR","aliases":["DVR","series voltage compensator","voltage sag corrector"],"category":"microgrid-systems","drawingTypes":["SLD"],"referenceFamilies":["IEC","IEEE / ANSI"],"summary":"A series converter that injects a corrective voltage through a transformer to ride a sensitive load through voltage sags.","description":["A dynamic voltage restorer is connected in series between the supply and a sensitive load through an injection transformer. When the supply voltage sags, a converter fed from a DC store or from the supply itself injects the missing voltage so the load sees an almost constant voltage, typically for sags lasting up to a few seconds.","Single-line diagrams show an injection transformer with its primary in series with the feeder, its secondary connected to a converter, and a DC capacitor or storage element. A bypass switch around the injection transformer allows the device to be taken out of service.","A DVR corrects sags but does not supply the load during a full outage, unlike a UPS. The symbol does not show the maximum sag depth or duration it can correct, which depends on the stored energy and converter rating."],"readingNotes":["The series transformer, not a shunt connection, identifies a DVR.","Check the bypass arrangement for maintenance."],"drawingChecklist":["State load rating, sag depth and duration corrected.","Show injection transformer and bypass.","Reference energy store."],"distinction":"A DVR injects series voltage for sags; a STATCOM injects shunt current to support bus voltage.","facts":[{"label":"Connection","value":"Series, through injection transformer"},{"label":"Corrects","value":"Voltage sags and swells"},{"label":"Outage support","value":"None"},{"label":"Preview","value":"Independent educational illustration; consult the applicable standard and project legend for the exact graphic"}],"references":[{"sourceId":"iec-diagrams","relevance":"IEC graphical symbol context for transformers and converters."},{"sourceId":"pub-electronics-infineon-inverter","relevance":"Public converter stage context."}],"related":["statcom","online-double-conversion-ups","power-transformer"],"artwork":"s28-dynamic-voltage-restorer","publishedOn":"2026-10-28","updatedOn":"2026-10-28","provenance":"independent-public-research","plainEnglish":{"title":"What does Dynamic voltage restorer mean?","introduction":"A dynamic voltage restorer is connected in series between the supply and a sensitive load through an injection transformer. When the supply voltage sags, a converter fed from a DC store or from the supply itself injects the missing voltage so the load sees an almost constant voltage, typically for sags lasting up to a few seconds.","example":"Single-line diagrams show an injection transformer with its primary in series with the feeder, its secondary connected to a converter, and a DC capacitor or storage element. A bypass switch around the injection transformer allows the device to be taken out of service.","drawings":"A DVR corrects sags but does not supply the load during a full outage, unlike a UPS. The symbol does not show the maximum sag depth or duration it can correct, which depends on the stored energy and converter rating.","terms":[{"name":"DC","meaning":"Direct current: electricity flowing in one direction."},{"name":"Winding","meaning":"A coil of conductor inside an electrical machine or transformer."},{"name":"Rating","meaning":"A value stating the conditions for which equipment is specified."}],"diagram":"flow","steps":["Identify the device and form","Read the connections and state","Check the equipment reference"],"caption":"A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram.","sources":[{"label":"IEC graphical symbols for diagrams","url":"https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/"},{"label":"Bidirectional three-/single-phase AC/DC PFC and inverter application note","url":"https://www.infineon.com/assets/row/public/documents/24/42/infineon-ac-dc-pfc-11-kw-high-efficiency-high-density-bidirectional-three-single-phase-inverter-applicationnotes-en.pdf"}],"detail":"A series converter that injects a corrective voltage through a transformer to ride a sensitive load through voltage sags. A DVR injects series voltage for sags; a STATCOM injects shunt current to support bus voltage.","profileId":"reviewed-symbol-20261028"},"url":"https://eloragrid.ai/symbols/dynamic-voltage-restorer","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/dynamic-voltage-restorer.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"iec-diagrams","title":"IEC graphical symbols for diagrams","publisher":"IEC","url":"https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/","type":"standard","scope":"IEC 60617 and related symbol-design publications. Full database access requires a subscription.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"IEC graphical symbol context for transformers and converters."},{"id":"pub-electronics-infineon-inverter","title":"Bidirectional three-/single-phase AC/DC PFC and inverter application note","publisher":"Infineon Technologies","url":"https://www.infineon.com/assets/row/public/documents/24/42/infineon-ac-dc-pfc-11-kw-high-efficiency-high-density-bidirectional-three-single-phase-inverter-applicationnotes-en.pdf","type":"manufacturer","scope":"Public application context for actively switched AC/DC and inverter stages. Independent miniature topology illustrations have no copied product-specific values, wiring layouts or control implementation.","checkedOn":"2026-10-14","reuse":"link-only","relevance":"Public converter stage context."}]}