Stubby79, you are right. In fact I did not realize I had another thread already, but I think this one is a bit more well thought.
Regarding the Toyota system (#3), I think this is the crux of question #2: I really do not know how it works. For instance, if I were to quote
https://priuschat.com/threads/power-...device.167349/, without MG1 the engine power cannot get to the wheels. That would be consistent with what you said about not being a mechanical link between engine and wheels.
That also means we are then limited by the RPM iand power the MG1 can handle (Gen 3 added more stuff to allow that motor to spin slower but the principle is the same).
https://en.wikipedia.org/wiki/Hybrid...ve#Power_flows seems to imply there can be a mode where the engine alone powers the wheels; from the argument above
that is impossible in the Toyota/Aisin system.
Regarding the Insight Hybrid (#3), I can see its motor helping the engine specially at low RPM where it is not efficient. And then at high RPM it would be collecting energy for the battery (Kinda like in the Top Gear where Jeremy Clarkson drove the BMW Hybrid, where he said if you wanted to charge the battery you should drive hard/fast).
Regarding #1, what you are saying is that the 800HP (ignoring the "for a few seconds" part since I consider that is a given because of the issues you enumerated) all electric?
Quote:
Originally Posted by Ecky
You can't get max horsepower out of both simultaneously because of the power bands for each - if the ICE is at redline, MG2 will need to be spinning much more slowly or even backward, preventing it from producing peak horsepower at any reasonable road speed. Additionally, MG2 may also not be able to produce peak horsepower without additional power sapped from the ICE via MG1 - the battery alone in these types of hybrids often isn't adequately large to provide peak energy requirements of the electric motor.
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While I understand that the engine and MG2 have different power bands -- I expect electric motors to reach their peak HP at lower RPMs than an engine -- the part of having MG2 spinning backwards confuse me: is it doing that to collect engine power that is not necessary to keep the desired road speed (like the MG1) or actually "fighting against" the engine? Also, how would that work if I have pedal to the floor and want to drive at its top speed?
Also, shouldn't a reduction gear on MG2 be able to shift where its peak power is compared to the engine?
Quote:
Originally Posted by cRiPpLe_rOoStEr
Most likely it limits the ICE to not go too beyond its peak torque RPM so often, as the electric motors provide an effect analogue to a CVT enabling the ICE to remain at higher efficiency levels.
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It does seem that the Toyota system is aimed to provide efficiency first and foremost, with any power tied down to what the motors, specifically MG2, can deliver. In other words, there is no point in building an engine that can deliver 600HP at 7500RPM since how much of that power will get to the rear wheels depends on MG1 being able to (a) transfer some of that power to MG2 and (b) create enough resistance (which requires energy) so a fraction of that power can go to the ring gear (MG2 + wheels).