[Kaelinator]

Hi y'all.

I'm in Austin at my new place and these electric busses are always pulling up. Huge busses. Gotta have big power for 'em. I can't find much information about them, but I'd really like to learn more about specific drivetrain components. Y'all know anything about them? I'll try to post a photo of one the next time one comes by, but I doubt it'd be of value.

Thanks!

 

[brian_]

There are a few manufacturers of large motors used in trucks and buses. Some are incorporated into the driven axle; others are mounted roughly where an engine-driven bus would have a transmission, driving a conventional axle.

Found in a quick search:

• Metro: Electric Fleet
• Capital Metro electric buses running longer than predicted, cutting emissions
• Austin becomes fifth city in Texas to purchase to Proterra battery-electric buses

Austin appears to have at least four 40-foot Proterra Catalyst® E2 buses and at least six 60-foot articulated ("bendy") New Flyer buses.

The Proterra model has changed (the Catalyst E2 has been replaced by the ZX5) but the motors are likely the same: the brand isn't listed, but the specs say one 205 kW motor per rear wheel (mounted on the axle), or one 250 kW motor (depending on option selected), which are the two systems listed on their Proterra Drivetrains for Commercial Electric Vehicles. For two motors mounted on the axle some other manufacturers just buy the ZF AxTrax AVE Electric Portal Axle, but Proterra apparently puts their own together... but they probably don't make the actual motors. Both systems include a reduction gearbox for each motor.

The Nova web page doesn't seem to show the articulated model, but the regular model is listed as having "TM4 Sumo HD electric powertrain 230 kW / 2700 Nm"; that's an example of using one motor to drive a conventional axle. TM4 was purchased by Dana, so it's now part of the Dana Spicer Electrified product line; the Sumo HD is their series of big motors for heavy vehicles.