> The motor’s performance on the dyno has exceeded even our most optimistic simulations
Not to take away from the exciting achievement, but I always found comments like this kindof unusual. Really, it exceeded even your _most optimistic_ simulations? If the high end of your simulated performance was below what you actually measured, I am worried that your simulation is seriously neglecting something. I used to work in decent depth with three phase bldc motors, so I feel I can say with some authority that these things _can_ be simulated, and while real world data is hard to exactly predict, getting something outside of the predicted range would generally be interpreted as a sign that your simulation isn't so good. But maybe this is just marketing-speak, and their simulations are actually totally fine.
I suspect they correctly simulated everything.
Then on the test stand they turned the dial to 11 and saw a number higher than the simulations.
Probably not reliable at that power level, but fine for a record announcement.
Short-term peak ratings for electric motors are always huge. You can put in higher voltages up to arc-over. More interesting is sustained output. 1 minute, 10 minutes, 1 hour, continuous duty. That's all about how well it can get rid of heat.
That's why electric motors have a "temperature rise" number on the data plate. That's the steady-state temperature increase from a cold start when run continuously at rated power.
In the low-tens of kg, I have to wonder if we will just start mass-producing a single motor and just change the driving electronics for different vehicles/applications. Eg: De-rating this motor via driving electronics for aviation to only produce 200hp would be interesting for experimental designs.
The weight and form factor looks excellent for small propeller planes. Yes, batteries are heavy, but the lightweight of the motor makes room for more batteries.
A typical Rotax 912 with accessories goes over 55 kg for 80 HP max and ~ 60 HP cruise. The 100 HP/75 HP version is around 65 kg. The same continuous power with this technology looks like a 5 kg motor and 60 kg of batteries for a direct replacement, if we consider the regular fuel tanks of 50-100 kg on some planes (I used to fly a plane that took 140 liters of fuel with a 100 HP Rotax, but it was modified) then there is enough battery for a flight school needs.
At what point can we just return to 1990s wheel sizes, add the motor to the wheel, and have the same unsprung mass as we have with today's gigantic wheels?
> weighed 28.8 pounds, and achieved a peak power of 550 kilowatts
How well does this scale down? Can I have a 550 watt motor that's 1/1000th the size and that weighs 0.0288 pounds? Would be nifty to have an e-bike without any visible motor.
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[ 26.3 ms ] story [ 1484 ms ] threadNot to take away from the exciting achievement, but I always found comments like this kindof unusual. Really, it exceeded even your _most optimistic_ simulations? If the high end of your simulated performance was below what you actually measured, I am worried that your simulation is seriously neglecting something. I used to work in decent depth with three phase bldc motors, so I feel I can say with some authority that these things _can_ be simulated, and while real world data is hard to exactly predict, getting something outside of the predicted range would generally be interpreted as a sign that your simulation isn't so good. But maybe this is just marketing-speak, and their simulations are actually totally fine.
Short-term peak ratings for electric motors are always huge. You can put in higher voltages up to arc-over. More interesting is sustained output. 1 minute, 10 minutes, 1 hour, continuous duty. That's all about how well it can get rid of heat.
That's why electric motors have a "temperature rise" number on the data plate. That's the steady-state temperature increase from a cold start when run continuously at rated power.
A typical Rotax 912 with accessories goes over 55 kg for 80 HP max and ~ 60 HP cruise. The 100 HP/75 HP version is around 65 kg. The same continuous power with this technology looks like a 5 kg motor and 60 kg of batteries for a direct replacement, if we consider the regular fuel tanks of 50-100 kg on some planes (I used to fly a plane that took 140 liters of fuel with a 100 HP Rotax, but it was modified) then there is enough battery for a flight school needs.
Anyhow, I rarely see more than 35 kW indicated for less than a minute at a time.
So can I get my 59kW/kg to go, please? I will take two kilograms.
If the engine is spun to produce electricity, does that make it any different?
These look small enough to use as the wheels. Just like that Audi that Will Smith drove in the film I, Robot.
How well does this scale down? Can I have a 550 watt motor that's 1/1000th the size and that weighs 0.0288 pounds? Would be nifty to have an e-bike without any visible motor.