Motor controller assembly

The motor controller components were installed in a 2U rack enclosure. It is not a watertight box but it can be sealed if needed. The heatsink was mounted on the bottom of the motor controller so that it sticks out from the enclosure.

The rack enclosure will be mounted close to the batteries and the motor to keep the power wirings short. The hall throttle can be seen next to the motor controller.

Electric gas pedal

The hall throttle pedal was modified so that corolla's original gas pedal and throttle cable could be used to actuate it. The hall throttle will be mounted in the same enclosure with the motor controller.

Main components for the motor control

The motor controller chosen for this project is Kelly Controls PM72401B. It's a 72V 160A continuous rated four quadrant dc motor controller capable of providing 400A current for short terms. In addition to the motor controller a 400A contactor with 72V coil voltage and a hall throttle pedal were bought from Kelly Controls. The fuse holder with 400A fuses were bought earlier from ebay.

Finished motor plate

Small pieces of 1,5mm steel was welded on the motor plate to fill the holes where splashing water could enter the clutch assembly. A small hole was left into the bottom of the motor plate similarly as with the original gasoline engine. The motor plate was then painted first with zinc containing paint and then with thick metal paint. This was ment to slow down corrosion.

After the paint work the motor was assembled back on its place. The corolla was given a second test drive and it could be noticed that the flywheel balancing had improved. It's not sure if the balancing is still good enough for the planned 3000rpm, but for 500rpm the balancing is now acceptable.

Flywheel balancing

The flywheel was mounted on a lathe using a rod with the same diameter as the motor shaft. It was then aligned using a dial gauge and the outer edge of the flywheel was machined to balance the flywheel better.

The motor plate will be given a finishing touch and then the motor will be mounted again to see if vibrations are now on an acceptable level.

Corolla's first test drive

The first test drive was performed without motor controller since it has not been purchased yet. Using start cables a 12V lead acid battery was connected to the motor while making sure that the gearbox was on neutral. The ME1003 runs approximately 500rpm unloaded with the 12V battery. The motor took about 14 amps while rotating the gearbox on neutral.

Moving the corolla forth and back was as easy as with any manual car. The clutch worked well and silently. A small vibration was noticed and the flywheel was decided to be balanced to fix the vibration.

From now on the tasks in the project should be more electric than mechanic. As shown in the picture there is a lot of room under corolla's hood. The motor controller, on-board charger and LiFePo4 batteries are planned to be installed next to the electric motor.