I’m planning on putting three motors on the car, making it “all wheel drive.” This makes motor control a bit more complicated as I need to have three separate motor controllers that are all linked to the same throttle. Multiple controllers can be linked together to form a “truck drive system” using the “CAN bus.” The front two motors would need to be operated as a “dual traction motor” setup, allowing the controllers to turn each one at different speeds, thus allowing for turning. So my plan is to have all three motor controllers share the same throttle input but to have the rear wheel operate independent and have the front two motors operate as a “dual traction motor” “twin motor system.”
I’m planning on using three Sevcon Gen 4 controllers. Since the Motenergy DLC-28 motors can accept a peak current of 480 AC amps, the motor controllers must be able to accept 660 DC amps. The motors are also capable of taking 180 AC amps of continuous current, so the motor controllers must be able to accept 220 DC amps of continuous current. The Sevcon Gen 4 Size 6 motor controller has a short-term (2 minutes) rating of 650 amps and a continuous rating of 260 amps. The next size down, the Sevgon Gen 4 Size 4, can only handle 180 amps of continuous current, so I’ll have to use the Size 6 controllers.
The Sevcon Gen 4 Size 6 motor controller:
Weight
Each Sevcon Gen 4 Size 6 controller weighs 4.6 kilograms without a heatsink. Combined this is 13.8 kilograms of weight (30.4 lbs). Unfortunately, there’s not much I can do to lower this weight – these components are absolutely essential and I haven’t been able to find any lighter controllers that do as much as these do. In order to save a bit of weight, I’m planning on integrating a heatsink into the body/chassis section where these controllers will be mounted. Since I’m planning on making the chassis out of aluminum – and most heatsinks are made of aluminum – this should be fairly straightforward.