I've been around; just haven't said anything...
As far as I understand, you can get away with an electric motor rated at less power than the gas motor it's replacing. Generally, the electric motor's torque at startup is much better. I would make sure the torque specs are what you need (for the gearing you're using and the accelleration you want for the mass off vehicle you're using) AND that the motor can produce adequate power at the top speed you intend to drive it at. ( If you're using a fixed gearing system - like the Toyota MGR - then make sure it can produce enough power at top speed AT THE VOLTAGE you're using. One downside of BLDC motors (like the MGR) is that they are also generators. The voltage they generate at high speed apposes the voltage the controller is putting into the motor, reducing the power output. This is why field oriented control is important AND why high voltages are required on some motors. Advanced designs like the MGR are also partially reluctance motors, which helps reduce this effect with proper field oriented control.
I guess in reality there are quite a few variables involved... the quick answer is that a motor rated at 50kW (the MGR) will definitely be an adequate replacement for a gas motor rated at less than half it's power. A more real answer would require a lot more details.
I've done a silly amount of spreadsheets and other simulations to make sure I don't end up with a slug. These calculations include vehicle drag coefficient and frontal area, vehicle mass, tire diameter, battery pack voltage, etc, etc...
BTW, I found one for you on E*bay:
AWD Rear Carrier Differential Engine 2008 Lexus RX400 with 76 500 Miles | eBay
The Lexus RX400 is mechanically the same as the Highlander Hybrid. This one looks a little rough; like it's been on salty roads a lot. You probably could find one in better condition...
- E*clipse
Quote:
Originally Posted by freebeard
Is there a one-to-one correspondence of the electric motor's output vs the gas engine it replaces? Because the VW Beetle started at 25hp and it was designed for the Autobahn.
e*clipse hasn't been back since another thread on the 18th. Do you know anymore about the Highlander Hybrid M/G? Do you need one for testing?
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