Allison Transmission unveils compact, advanced e-axle ultra-low floor electric bus powertrain

At the Advanced Clean Technology Expo, Allison Transmission, a global leader in medium- and heavy-duty propulsion solutions for commercial vehicles, is introducing the new ABE Series, the first e-axle advanced ultra-low floor electric bus powertrain system in the market. The ABE Series e-axles are one of the world’s most powerful and compact fully integrated electric axles for the transit bus market.

The ABE Series integrates dual electric motors, a single- or multi-speed gearbox (depending on e-axle model), oil coolers, pumps and power electronics into a bolt-in system that replaces the entire traditional powertrain within the existing frame. It meets the power and space demands of the transit bus industry, including heavy double-decker, articulated and 3-door buses.   

“Allison Transmission’s depth of experience in the bus and transit market demonstrates our continuous commitment to innovation. We have a long history with electric hybrid solutions and full electrification is the next evolution,” said David S. Graziosi, Allison Transmission President and CEO. “The ABE Series replaces the traditional powertrain system with the most compact, powerful electric propulsion system available.”

The Allison ABE Series can operate without restrictions at regular highway speeds, and on all allowable grades.  The system can handle 100 percent torque in regenerative braking. With an axle rating up to 28,660 pounds (13 tonnes), the system provides more power and torque than any other e-powertrain system in its class on the market. With a dual motor, it has continuous axle output power of 536 horsepower (400 kilowatts) and peak output power of 738 horsepower (550 kilowatts). A single speed e-axle option also is available. Its proprietary cooling allows for industry-best continuous motor power and allows the vehicle to run closer to peak power for longer durations.

An attractive feature for bus manufacturers is the system’s compact design. The bolt-in ABE Series fits existing bus frames and suspensions, creating more space for battery packs and other critical electric vehicle components. The standard system is configured for a 28-inch (700-millimeter) walk through, but has an optional 39-inch (1,000-millimetre) configuration. This makes the system applicable for 12-metre low-floor city and double-decker buses, 18-metre articulated buses and 3-door buses.