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Old 03-16-2019, 05:40 AM
Desert Mariner Desert Mariner is offline
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Join Date: Oct 2018
Location: Lost Pines
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Default More on drive motors

Without details such as amperage, voltage, etc. it’s seemingly impossible to properly size motors powered with a fictional fusion power plant.

I did find that for Tesla motors the Max. Motor Power (output kW) equals approximately 162% of the Max. Battery Power (input kW). This was explained in a 2012 Tesla.com forum post as follows:

“Here is is simple layman explanation. Without the technical electrical limitations stuff.
You have an electric motor that has a specific amount of power. You have a car that this motor is in. Obviously this motor doesn't have infinite RPM climbing possibilities . Being an electric though, means you have all that power available to you the second you hit the accelerator.
But now lets put this into context.
At rest, all that power gives you the torque that the model S has so far been praised for. "AT REST" and let me add "CLIMBING". This power gets the MS to say 100mph. Now think of it, if something was turning at 16,000rpm from rest to get you to 100mph as quickly as possible (considering weight..etc), do you realize that unless it starts turning at say 20,000rpm; it gets to a point where turning at 16,000rpm stops having as noticeable an affect on a car already doing 100mph as compared to one that was at rest. At that point, there is no need to even draw that much power anymore considering the car is already going "fast" all you have to do is draw enough power to make it go faster and at a more relaxed pace.
At 100mph, and being held there... the MS may actually be drawing less power cause it doesn't need to draw that much power to get itself up to speed and only needs to intermittently draw just enough juice to maintain your current speed. Think of it as using you hand to spin a fixed bicycle wheel, to get it up to speed you constantly apply force to the wheel, at say two turns every second. Once up to speed though, all you need to do is turn it once every 20 seconds to maintain that current speed.”


If this is applied directly to a 200kW fusion plant (input), the total drive motor output available would be approximately 326kW. Thus, I propose changing the drive motors as follows:

MTV 4x4 ICE engine produces 370hp (276kW) and 925ft-lb.
MLV motor produces 275hp (205kW) and 925ft-lb.

MTV (4x4): To match the ICE hp output, we need four (4) 70kW (94hp) electric motors producing a total output of 280kW (375hp), drawing a total of 172kW (input).

MLV (4x4): To (nearly) match the ICE hp output, we need four (4) 50kW (67hp) producing a total output of 200kW (268hp), drawing a total of 123kW (input). Alternatively, the 70kW motors above could be utilized.

MLV (6x6): To match the ICE hp output, we need six (6) 50kW (67hp) producing a total output of 300kW (402hp), drawing a total of 184kW (input).
Torque for individual motors would be 250ft-lb (339N-m), giving the 4x4 models a total of 1000ft-lb (1356 Nm) and the 6x6 models 1500ft-lb (2033 Nm). Since the 6x6 variants tend to be heavy haulers (i.e. wreckers, dump trucks, line haulers, etc.) I see no reason to “create” a separate motor with lower torque.
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