Archives

In my quest for the best demo of the Prius power split device I realized something interesting.
If the gas engine was removed from the car, and the power split device planet gears were welded to the carrier, the Prius drive system could be pure electric at full speed. This configuration uses the two motors. MG1 at about 13 hp, and MG2 at about 40hp, to yield a 53 HP BLDC drive with the same differential.
The power IGBT transistors in the Inverter could be driven by a new dual BLDC driver board that would have to be developed.
The other interesting thing about this configuration is that the splined ICE input shaft that the oil pump is working from is turning,thus good lube. The ICE input shaft is now a power output device that could be connected directly to a rear end of any 4 wheel drive car.
Very Interesting.:cool: ;)

Hi Mike:

___I have read more then once that that if you could jam a screw driver through MG1, the EV Speed limitations would be removed and full speed EV off of MG2 would be a gimme. Similar solution I guess?

___I have also read that MG1 has a 10K RPM limit yet only reaches around 3,600 at 41 mph? I have to look this up again but like Ford, I believe the real limitation is that you approach a minimum starting torque to spin up the ICE at a 41 mph maximum speed, not an actual MG1 RPM limitation?

___Another tidbit I read about is that Toyota has a few patents on a higher speed EV Mode lubrication (as does Ford) so a std. PHEV may be nothing more then clutching MG1 to a brake, a more powerful MG2, larger pack and the EV mode - full lubrication HW installed? What do you think about this?

___I actually have no idea what Toyota will bring to the table with the Prius III. The rumor mill is so loaded with misleading information from Toyota exec’s spreading FUD from one end of the globe to the other I do not know what or who to believe anymore? Probably to keep Ford, GM, DCX, Honda and whoever else off guard more then likely?

___A bit OT. Toyota really likes Trucks and SUV’s and we know that is because of the money potential in the darn things … Just like everybody else :(

___Good Luck

___Wayne

While my idea is a bit difficult to envision, it will allow the Prius transaxle to become an integrated electric drive, with differential, and auxiliary input/output shaft, and full self lubrication.
MG1 turns the whole welded planet carrier(planet gears welded so they can't turn) as a single unit, and MG2 via the ring gear also turns this planet assembly, which acts as a coupling between the two motors, rather than a power split device.This rotation of the planet assembly runs the oil pump so the tranny is kept lubricated. MG2 also drives the transaxle as it does in the stealth mode, but with the planets frozen, MG1 turns at the same rpm as MG2, so both or either can be a generator or motor.
I hope to get another Prius transaxle in the near future and try it out.

In the stock configuration, as I understand it, the 42MPH stealth limit when the engine is stopped, is determined by the top speed of MG1, which turns 3 times faster than MG2.

It seems clear based on GM and Fords recent news releases, that they are hearing the people about the need for a real fully functional Electric mode, and may gain an edge over Toyota and Honda by producing a series Hybrid with various auxiliary on board power sources including diesel, gas, and fuel cell. Lets hope it happens in time.
It will be an interesting next few years.

http://techno-fandom.org/~hobbit/cars/Nomograph-plus-PSD.gif
.
MG1 6500 RPM limit in the Classic, 10000 in the 3rd-gen but
the system still treats it as though it were 6500 and has
the same 42-mph threshold. I know from personal warp-neutral
experiments [68 mph downhill, engine RPM = 0, do the math]
that it's good for the 10000 RPM limit...
.
_H*

Hobbit,
any idea what MG1's unconditioned output voltage is when whipping at 10000 RPM ?