new all-electric motorcycle built by Brammo Inc. is using a MPP series traction
motor and innovative cooling technology to maximize power density and peak
torque output. The motor technology yields up to 40 percent higher torque per
unit size than conventionally constructed permanent magnet motors, and delivers
20 to 350kW of power with 97 percent efficiency.
The Brammo bike was unveiled at the Red Bull
US Grand Prix at the Mazda Raceway in Laguna Seca, CA, where a major race took
place as part of the FIM e-power race series.
What the MPP traction motor
technology embodies is a high-efficiency solution that offers broad scalability
and manufacturability. But from a performance and technology standpoint, what creates
the high motor power density that fits well into electric vehicles is innovative
cooling technology that maximizes motor performance.
"We've added a dual cooling system to our
motors that features patent-pending dry-rotor internal cooling technology,"
says Jay Schultz, a product manager for Parker's Electromechanical Automation
Div. "As we implement these on our motors, it increases the peak power output
up to four times."
Schultz says that, for example, if a standard
motor has a power output of 20 kW peak, the equivalent MPP traction motor will
output 80 kW peak, with very little added weight. The difference is largely attributed
directly to superior cooling of the motor which significantly increases power
Internal cooling also raises the continuous
power of the motor by 8.5 times because as the race bike is accelerating
outside of every curve, maintaining continuous power as high as possible is
extremely important in the dynamics of how the bike operates.
"If you think about what causes torque, it is
the current inside of the motor windings. When you are running current through
the windings, there are losses but our internal cooling extracts losses in the
form of heat by taking them directly from the windings back out to ambient,"
typical application, losses go from the winding, to a lamination, the case and
finally to ambient. But with this technology, losses in the form of heat move directly
from the windings to ambient which improves continuous power output
Target electrification applications for the
MPP technology include jet skis, forklifts, compact cars, sedans, vans, light
duty trucks, high-performance sports cars, medium duty trucks, large boats,
buses and Class 8 trucks. Across all of these applications, the internal and
external cooling technology has been employed, but dual cooling is particularly
useful where there is aggressive power usage such as marine applications, Class
8 trucks and this electric race bike.
"With other vehicles such as a
sports car where you are running primarily at very high speeds, the application
is not continuously requiring high continuous power from the motor," says
Schultz. "With this application, we took the power density of the motor to the
max and squeezed it into the tightest possible package."
When the bike makes its debut in September, Brammo
is hoping that the leaders in the racing circuit will have a serious new
contender vying to capture the winning trophy. Brammo also plans to market a
street version of the race bike for the commercial market next year. Brammo and
Parker are working through the details around a smaller MPP motor for the
to read the Parker Electromechanical Automation blog.