| Revision as of 17:08, 19 October 2004 edit198.51.251.205 (talk) Significant rework to add TGV comments.← Previous edit | Revision as of 00:09, 20 October 2004 edit undo66.31.67.154 (talk) Added hyperlinks for bogie/bogiesNext edit → | ||
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| Traditionally, these are large ] series motors usually running on approximately 600 volts. Nowadays, the availability of high-powered semiconductors (such as ] and the ]) has now made practical the use of much simpler, higher-reliability ] induction motors. Synchronous ac motors are also occasionally used (as in the ]). | Traditionally, these are large ] series motors usually running on approximately 600 volts. Nowadays, the availability of high-powered semiconductors (such as ] and the ]) has now made practical the use of much simpler, higher-reliability ] induction motors. Synchronous ac motors are also occasionally used (as in the ]). | ||
| In ancient days, a single large motor was used to drive multiple driving wheels through connecting rods that wewre very similar to those used on steam locomotives. It is now standard practice to provide one traction motor driving each axle through a gear drive. Usually, the traction motor is simply suspended between the truck (bogie) frame and the driven axle; this is referred to as "nose drive". Occasionally, other mounting arrangements are made. In the case of the ], two truck-mounted motors drove each axle through a ]. In the case of the ] power units, each axle is driven by a motor mounted to the power unit's frame; a "tripod" drive allows a small amount of flexibility in the drive train allowing the trucks (bogies) to pivot. By mounting the relatively-heavy traction motor directly to the power unit rather than to the truck (bogie), better dynamics are obtained allowing much-improved high-speed operation. | In ancient days, a single large motor was used to drive multiple driving wheels through connecting rods that wewre very similar to those used on steam locomotives. It is now standard practice to provide one traction motor driving each axle through a gear drive. Usually, the traction motor is simply suspended between the truck (]) frame and the driven axle; this is referred to as "nose drive". Occasionally, other mounting arrangements are made. In the case of the ], two truck-mounted motors drove each axle through a ]. In the case of the ] power units, each axle is driven by a motor mounted to the power unit's frame; a "tripod" drive allows a small amount of flexibility in the drive train allowing the trucks (]) to pivot. By mounting the relatively-heavy traction motor directly to the power unit rather than to the truck (]), better dynamics are obtained allowing much-improved high-speed operation. | ||
| Because of the high power levels involved, traction motors are almost always cooled using forced air. | Because of the high power levels involved, traction motors are almost always cooled using forced air. | ||
Revision as of 00:09, 20 October 2004
"Traction motor" typically refers to those motors that are used to power the driving wheels of a railroad locomotive.
Traditionally, these are large dc series motors usually running on approximately 600 volts. Nowadays, the availability of high-powered semiconductors (such as thyristors and the IGBT transistor) has now made practical the use of much simpler, higher-reliability ac induction motors. Synchronous ac motors are also occasionally used (as in the TGV).
In ancient days, a single large motor was used to drive multiple driving wheels through connecting rods that wewre very similar to those used on steam locomotives. It is now standard practice to provide one traction motor driving each axle through a gear drive. Usually, the traction motor is simply suspended between the truck (bogie) frame and the driven axle; this is referred to as "nose drive". Occasionally, other mounting arrangements are made. In the case of the GG1, two truck-mounted motors drove each axle through a quill drive. In the case of the TGV power units, each axle is driven by a motor mounted to the power unit's frame; a "tripod" drive allows a small amount of flexibility in the drive train allowing the trucks (bogies) to pivot. By mounting the relatively-heavy traction motor directly to the power unit rather than to the truck (bogie), better dynamics are obtained allowing much-improved high-speed operation.
Because of the high power levels involved, traction motors are almost always cooled using forced air.