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The SNCF BB 26000 locomotives are a class of dual voltage, four axle B'B' electric locomotives capable of a top speed of 200 km/h built by GEC Alsthom between 1988 and 1998 for SNCF. The locomotives are also commonly known as the ''Sybics''.〔From ''Synchronous Bicurrent'', referring to synchronous motor drive, and dual voltage operation (French: ''Synchrone Bicourant'')〕 ==Design and development== The class were built to fulfil both freight and passenger roles; the specifications included the ability to haul 16 Corail coaches at on a 0.25% gradient, and to haul a freight train at on a 0.88% gradient. The locomotives are a two cabin design with the body built out of steel, two pantographs are fitted; one for 1500 V operation, the other for 25 kV operation.〔 A 25 kV AC supply is stepped down and rectified to 1500 V, a 1500 V supply feeds the power electronics directly. Each of the three elements of the thyristor bridge based〔The back EMF (ie electrical generator effect) of the synchronous motor provides a reversed electric potential forcing the commutation of the thyristor. A separate circuit commutates the thyristor at low speeds.〕 three phase inverter circuits are connected in parallel, with the two three phase supplies per motor being series connected. For speeds below one supply voltage reducing chopper circuit (French:''hacheur'') per motor bogie is used to assist control. The power electronics of the two motor bogies are connected in parallel,〔〔 and are evaporatively cooled by boiling Freon 113.〔 The bogies are a ''monomoteur'' design,〔''Monomoteur'' (English: mono-motor or single motor) - a single (2.8MW) electric motor is mounted in the bogie and drives both axles〕 with helical spring primarily suspension.〔 The traction motors are three phase synchronous type (as used in the contemporary TGV Atlantique) but with two three phase stator windings offset by 30 degrees.〔A "double star" (French: ''double étoile'') type with 12 pole elements was used for the BB 26000 locomotives, whereas the single three phase motors used in the TGV Atlantique had only 6 stator poles set 60 degrees apart〕 Drive from the traction motors to wheel is via a floating ring vibration isolation element (French:''anneau dansant'') and hollow shaft drive.〔 Mono-motor bogies were chosen based on the good performance in the SNCF BB 22200, SNCF BB 15000 and SNCF BB 7200 classes. A synchronous motor was chosen over a commutated motor or an asynchronous motor due to the reduced mass, simplicity of equipment, and price. Two locomotives SNCF BB 20011 and 20012 were used to develop and test the dual voltage traction system, microprocessor control systems and auxiliary motors, BB 20012 was used to develop and test the pneumatic and electrical braking system.〔 The Paris-based industrial design group MBD Design contributed to the design of the locomotive.〔(【引用サイトリンク】title=BB26000 )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「SNCF Class BB 26000」の詳細全文を読む スポンサード リンク
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