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Pulse and glide is a proven technique for a significant increase in mileage, because it limits engine operation to only the most efficient ranges of RPM and load.
The problem has always been, how do you maintain a constant vehicle speed, while employing P&G?
How do you design a power train system that maximizes the potential gains from improved aero and lower rolling resistance?
To accomplish this you MUST disconnect the engine from the wheels, while maintaining constant velocity, at every legal speed.
You MUST have some form of capacitive storage for the energy generated by the engine, that can be applied to the power train in precise and constantly changing levels,thus allowing the engine to cycle on and off at varying frequencies depending on average sustained load.
The application of that power as well as the storage of same power MUST be accomplished at levels of efficiency approaching that of a conventional manual transmission. Wheel to wheel regeneration of braking energy MUST exceed 80%, not including aero and rolling resistance factors.
The system MUST automatically compensate fro any improvement in aero or rolling resistance without having a directly connected engine's efficiency fall off as sustained load is decreased.
No hybrid electric vehicle can overcome the cumulative losses inherent in the multiple conversions of energy necessary to provide power to the wheels with the engine off at freeway speeds.
My system reduces the parts count by about 25 % per vehicle, while providing regenerative braking efficiencies of over 80%, wheel to wheel. It can be done by replacing the rear axle in a FWD car with a launch assist unit in its simplest configuration.
Even this most basic system would allow constant speed P&G by increasing the load on the engine during the pulse phase, then applying that same stored energy to the rear wheels while the FWD power train is in neutral with the engine shut off.
Now you do not have to use the vehicle's mass as capacitive storage, and suffer the consequences of the frustration of other drivers when you are constantly accelerating and decelerating.
You do not have to suffer the much higher aero losses of the exponential effects of drag at your peak pulse speeds.
In fact no other drivers around you would even realize that you are actually turning your engine on and off regularly, and the cycling between running and not running would be automatic, controlled by the percentage of your stored reserve capacity.
P&G goes back to WW2 and even before.
ALSO;
For those who are convinced that battery powered vehicles are the future, what I have just describes, in no way, is restricted to any particular fuel or motor configuration. The energy path to regenerate the capacitive storage can be by any means, without exception or limitation.
regards
Mech
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