Electric Motor Dynamometer
With the help of a DC Motor Dyno, the Electric Vehicle controller hardware is load tested before it is
shipped out. In this recent photo, the WarP 9 (top motor) is under control of the DC motor controller, and
the bottom AC motor generates power to go back to the battery pack. The battery pack consists of 12
Genesis AGM's with 144V on tap. This allows very high power levels to be used and the energy lost in the
process is supplied by the AC line. I noticed a potential vibration problem, the tail of the motor can move
left to right with sufficient force. The tail end is now supported with a cross beam.
Rev 1
This Dyno below had problems
with the belt skipping teeth after a
few runs (with 1" wide pulleys)
with 350A-400A at the motor. It
has now been replaced with much
wider 3.5" pulleys and belt on the
right, along with a massive idler to
transmit torque to the load cell.
No more belt skipping and
500A+ current capability! When
the current is cranked up, you can
hear the belt start to whine!
LabView below helps with the data collection efforts on the new Dyno. Some results are here for this 6.7"
ADC motor. Not only has it held up, but performed better than expected for such a small motor!
Battery Pack is 144VDC for this test
Rev 2
With the Dyno on the bottom,
this little 6.7" ADC motor
produced ~65ft/lbs of torque at
500A of motor current...Not
bad for a motor this size. The
new Dyno was built with torque
production in mind. Teflon
guides were used in the new
Dyno, to help stabilize the belt
under load. A much larger idler
was needed to handle the 3"
wide belt.
Dyno History:
Right: On 1/7/09 a WarP 9 motor is
installed on the dyno stand to power
the BLDC motor as a generator.

The 6.7" ADC is retired from service.
Dyno Rev 4: Got a 20HP AC motor
mounted to the stand and now its
generating power back to the battery
pack. Still more to update, the load
cell plate (right vertical beam) is flexing
under load. (6/17/09)
See the WarP DC motors link for
dyno plots!