Maybe I don't get it at all, but after watching the Weber videos, my understanding is the ICE crankshaft is geared to the output drive shafts. I did not see any changeable gearing. Did I miss it? Does a 'power split device' cause variations in the gearing of the ICE crankshaft to the wheel rpms? Seems what I saw, the engine rpms will continue to rise directly as speed changes. What did I miss?Thank you. I'm familiar with this kind of modeling, so let me tell you what else I see. I don't know for certain what drivetrains these represent, but the general pattern is consistent. I would call this a drag race analysis: straight "floor it off the line." You run up the maximum torque or HP curve in 1st gear, then shift to successively higher gears. Undulations are shift points where RPM and output drop. Torque falls because it includes a decreasing numerical gear ratio at each shift.
This works for any system where the power plant and the road are mechanically connected, virtually anything with a geared transmission be they EV, hybrid or conventional powerplant. Of the four drivetrains, three are geared so the model is valid. It's also valid with any EV. Assuming the fourth is Escape Hybrid, such a model is not valid.
Hybrid engine RPM is not linked to road speed, so relating ICE output to a "speed" axis is meaningless. Traction motor is linked directly to the road, but the ICE is connected through the power split device, and that changes everything. The ICE can run at peak torque RPM at any road speed. EV torque is first current-limited, then RPM limited, but ICE speed and so ICE torque can remain constant as you speed up.
You can understand why it needs a sophisticated control system...
tom
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