Hi! anybody knows what's the best transmission for an electric engine?
Hi! anybody knows what's the best transmission for an electric engine?
Júlio Soares
Cheetah Racing - UNIFEI FSAE
PowerTrain
No, because there is no "best" transmission.
How many motors due you use? Only in the rear or in the front, too?
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Alumnus
AMZ Racing
ETH Zürich
2010-2011: Suspension
2012: Aerodynamics
2013: Technical Lead
2014: FSA Engineering Design Judge
Only one motor in the rear. My doubt is how I will get greater efficiency, using a CVT system or a 2 or 3-speed transmission.
Júlio Soares
Cheetah Racing - UNIFEI FSAE
PowerTrain
10 speed chain drive, like on a bicycle. Obviously you could upgrade to like a fancy 27 speed for more horsepower, but that would just be ridiculous.
Owen Thomas
University of Calgary FSAE, Schulich Racing
Julio,
Good manners to introduce yourself and say what team you represent.
Electric motors develop maximum torque at zero RPM, so it may be that you only need a sprocket and chain to drive the rear wheels.
Pat
The trick is ... There is no trick!
Pat,
I'm sorry. I'm newbie in this forum and in my team, and this is our first project of electric vehicle, so the doubts are many. Thanks!
Júlio Soares
Cheetah Racing - UNIFEI
PowerTrain
Júlio Soares
Cheetah Racing - UNIFEI FSAE
PowerTrain
Pat's hint is good, but also keep in mind cooling. While you might be able to get away with low ratios, this might create higher currents and thus uses your wires and coils as heaters instead of actual movement to the wheels.
General rules: Low rpm means high torque but also high current and low efficiency. Max efficiency is usually around 70-80% of max rmp. Max. power usually around 50%. So you have to find the correct max-rmp for your car/engine.
There is also some difference in engine configurations (dc, dc/ac synchro or asynchro), but most teams use synchro engines anyway.
Tristan
Delft '09 Team member, '10 - Chief Electronics
'now' (Hardware) Security Engineer