[rone]

Being an engineer at heart I get high on the many advanced features of the Insight. Did you notice the recent Jag ad where they tout the aluminum frame? That's a cool feature. The low drag is another cool one. Sitting at a light and my engine isn't running, but everyone else's is....

The list goes on, but the feature that I just can't stop thinking about is how the IMA acts as an electronic flywheel. From http://www.insightcentral.net/KB/faq-im ... ologyRoles. "The electric motor is timed to smooth the gasoline engine. At idle speed, the electric motor actually operates in generation mode at the moment of ignition, when the gasoline engine is producing the most power. A moment later when the gasoline engine's crankshaft then begins to slow down, the electric motor operates in assist mode, reapplying the energy it absorbed, greatly smoothing the engine's idle."

That is really neat feature. So there is really no such thing as the IMA "coming on". It's always on and helping out. Sometimes it's adding torque, and sometimes just acting to smooth things out as a torque neutral part. A real flywheel is never neutral as it has considerable inertia and it never adds torque.

To me, the IMA seems like sort of a flywheel that's alive.

 

[Will M]

The "electric flywheel" has at least three advantages over a normal one:

1. It allows the engine to be built with a lighter physical flywheel than it would otherwise use, saving engine weight. On a car with a carbon-fiber dip stick, they obviously value this.

2. The energy saved and then used acts on a large (climb a hill, get up to highway speed from a standing start) scale and a small (smooth out the engine) scale, simultaneously.

3. During accelleration, a physical flywheel requires additional energy to overcome its own inertia. The electric one doesn't. Similarly, during decelleration, the electric one can choose several different degrees of drag to apply during regenerative braking. This is a trick a physical flywheel can't do, unless you do sophisticated work with a CVT transmission, and then the energy you store is likely to be quite a bit less than the Insight stores in its battery.