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Close, the prius drivetrain is two brushless 3 phase motors nested in one another. This allows regenerative braking and charging while still providing power to

by alvern 10y ago

Close, the prius drivetrain is two brushless 3 phase motors nested in one another. This allows regenerative braking and charging while still providing power to the final drive. Fun fact the ICE in the prius is an (1) Atkinson cycle which operates at a specific efficiency instead of a powerband. The engine revs up to a low or high range but doesn't have a traditional linear powerband. [1] https://en.wikipedia.org/wiki/Atkinson_cycle https://en.wikipedia.org/wiki/Atkinson_cycle

lloeki 10y ago
There's another notable Atkinson engine in some petrol Honda Civic Euro FK2 (2006-2011), can't remember engine code, but on that one i-VTEC is able to let inlet valves up during the beginning of the up stroke compression phase, turning the 140hp 1.8l engine into down to a 1.6l one. Turbo-less downsizing with all the benefits of a full-size (aluminium, so lightweight) block. Interesting tech. I owned one, the resulting fuel economy puts diesel engine to shame.
- lloeki 10y ago
  (edit expired) Engine is R18A2.
Gibbon1 10y ago
Yeah. What I though was neat about the Hybrid Synergy drive is how they use the strength of each component to compensate for the weakness of the others. Atkinson drive: very efficient, but over a narrow speed and output range. Mechanical gear train: Inefficiencies in the high nineties. But gear ratios are fixed. Electric drive train: Not as efficient as a mechanical gear trains, but is efficient over a very wide speed range. Add those up and you have a high efficiency mechanical power path through the planetary gear. And you use the electric power path to divert enough power from the engine to keep it running at it's most efficient. Because you have the electric power path you can cycle energy to and from the battery. Which gives you regenerative breaking, and allows you to stop the engine completely when you don't need power. Genius!

by alvern 10y ago

lloeki 10y ago

There's another notable Atkinson engine in some petrol Honda Civic Euro FK2 (2006-2011), can't remember engine code, but on that one i-VTEC is able to let inlet valves up during the beginning of the up stroke compression phase, turning the 140hp 1.8l engine into down to a 1.6l one. Turbo-less downsizing with all the benefits of a full-size (aluminium, so lightweight) block. Interesting tech. I owned one, the resulting fuel economy puts diesel engine to shame.

lloeki 10y ago
(edit expired) Engine is R18A2.

Gibbon1 10y ago

Yeah. What I though was neat about the Hybrid Synergy drive is how they use the strength of each component to compensate for the weakness of the others. Atkinson drive: very efficient, but over a narrow speed and output range. Mechanical gear train: Inefficiencies in the high nineties. But gear ratios are fixed. Electric drive train: Not as efficient as a mechanical gear trains, but is efficient over a very wide speed range. Add those up and you have a high efficiency mechanical power path through the planetary gear. And you use the electric power path to divert enough power from the engine to keep it running at it's most efficient. Because you have the electric power path you can cycle energy to and from the battery. Which gives you regenerative breaking, and allows you to stop the engine completely when you don't need power. Genius!