{"schemaVersion":1,"slug":"gas-turbine-generator","name":"Gas turbine generator","kind":"symbol","abbreviation":"GTG","aliases":["combustion turbine generator","CTG","turbine-driven alternator"],"category":"microgrid-systems","drawingTypes":["SLD"],"referenceFamilies":["IEC","IEEE / ANSI"],"summary":"A combustion gas turbine coupled to a synchronous generator, often through a gearbox, shown as a generating unit.","description":["A gas turbine generator uses a continuous-combustion turbine to drive a synchronous generator, often through a reduction gearbox for smaller industrial machines. Units range from microturbines of tens of kilowatts with high-speed alternators and inverters, up to large industrial turbines feeding a medium-voltage bus.","The drawing usually shows a turbine glyph, a trapezoid widening in the direction of flow, joined by a shaft line to the generator circle. A generator step-up transformer, generator breaker and neutral earthing equipment follow on the single-line diagram.","Microturbines with high-speed alternators produce high-frequency output that must pass through a rectifier and inverter, so check whether a converter sits between the machine and the bus. The symbol does not state fuel, start method or ambient derating."],"readingNotes":["A trapezoid on the shaft line indicates the turbine; a gearbox may be drawn as a small box between turbine and generator.","Look for a converter stage on microturbine packages."],"drawingChecklist":["State ISO rating and site derating.","Show gearbox, generator breaker and earthing.","Reference start system and black-start capability."],"distinction":"A gas turbine is a continuous-combustion rotating prime mover; a gas engine is reciprocating.","facts":[{"label":"Prime mover","value":"Combustion turbine"},{"label":"Coupling","value":"Direct or through gearbox"},{"label":"Microturbine variant","value":"High-speed alternator with converter"},{"label":"Preview","value":"Independent educational illustration; consult the applicable standard and project legend for the exact graphic"}],"references":[{"sourceId":"ieee-315","relevance":"Graphic-symbol standards context for machines and prime movers."},{"sourceId":"pub-symbol-station-types","relevance":"Public power station representation context."}],"related":["three-phase-synchronous-generator","gas-engine-generator-set","generator","87g-generator-differential-protection"],"artwork":"s28-gas-turbine-generator","publishedOn":"2026-10-28","updatedOn":"2026-10-28","provenance":"independent-public-research","plainEnglish":{"title":"What does Gas turbine generator mean?","introduction":"A gas turbine generator uses a continuous-combustion turbine to drive a synchronous generator, often through a reduction gearbox for smaller industrial machines. Units range from microturbines of tens of kilowatts with high-speed alternators and inverters, up to large industrial turbines feeding a medium-voltage bus.","example":"The drawing usually shows a turbine glyph, a trapezoid widening in the direction of flow, joined by a shaft line to the generator circle. A generator step-up transformer, generator breaker and neutral earthing equipment follow on the single-line diagram.","drawings":"Microturbines with high-speed alternators produce high-frequency output that must pass through a rectifier and inverter, so check whether a converter sits between the machine and the bus. The symbol does not state fuel, start method or ambient derating.","terms":[{"name":"Winding","meaning":"A coil of conductor inside an electrical machine or transformer."},{"name":"Signal","meaning":"Electrical information passed between devices, rather than necessarily the main power supply."},{"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":"IEEE/ANSI 315-1975: graphic symbols for electrical and electronics diagrams","url":"https://standards.ieee.org/ieee/315/515/"},{"label":"AutoCAD Electrical: Power station and substation concepts","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-74EF80E8-018D-4A57-88BD-FF973F1B8185.htm"}],"detail":"A combustion gas turbine coupled to a synchronous generator, often through a gearbox, shown as a generating unit. A gas turbine is a continuous-combustion rotating prime mover; a gas engine is reciprocating.","profileId":"reviewed-symbol-20261028"},"url":"https://eloragrid.ai/symbols/gas-turbine-generator","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/gas-turbine-generator.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"ieee-315","title":"IEEE/ANSI 315-1975: graphic symbols for electrical and electronics diagrams","publisher":"IEEE Standards Association","url":"https://standards.ieee.org/ieee/315/515/","type":"standard","scope":"Graphic symbols and designation letters. IEEE lists this edition as Inactive-Reserved; it is a historical reference, not a claim of current compliance.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Graphic-symbol standards context for machines and prime movers."},{"id":"pub-symbol-station-types","title":"AutoCAD Electrical: Power station and substation concepts","publisher":"Autodesk","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-74EF80E8-018D-4A57-88BD-FF973F1B8185.htm","type":"cad-reference","scope":"Public vendor catalogue naming and functional variants. Vendor block names are not IEC identifiers. Linked for reference; no graphics or CAD files are redistributed.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Public power station representation context."}]}