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by Gibbon1 1476 days ago
I'm not positive that a hybrid is actually that much more complicated than a traditional drive train with an engine + automatic transmission.
3 comments

It isn't. There's a transfer case between the electric drive and the gasoline engine. It's not that complicated, basically a planetary gear mechanism, and is pretty rugged and trouble-free.
Exactly. In fact hybrid is easier on the ICE since it takes a lot of load while starting the car and during acceleration. So, they, IMHO, have longer life than just ICE cars.
Agreeing with others, it might be less complicated.

With the generally accepted drive train (pioneered by Toyota, and adopted by everyone else), there's two electric motors instead of one, but the gearing between the engine, the two motors, and the output shaft is fixed. There's no transmission actuators to break (other than the park pawl, but that's pretty simple). You can still have problems of course, Ford messed up something on early HF35 transmissions and many of them have bearings fail, leading to a short service life (mine was covered under warranty, so now I've got a new transmission).

Is THS-like hybrid system now common? For Japanese manufacturers, only Toyota uses THS-like system. AFAIK Germans too. I've researched past for my curiosity, but it seems that parallel-hybrid is more common for worldwide. Chrysler Pacifica also looks like THS-like. I wish manufacturers open how system work.

This article covers well (Japanese but figures are English so not block machine translation). https://anopara.net/2016/03/11/%E5%90%84%E7%A4%BE%E3%81%AE%E...

I found is also somewhat hard to get good info on these systems. It's colored by knowing they are five/six axis machines[1] where you have one or more motors controlling an axis.

A three axis machine is a triangle. Think three linkages pinned. Not very interesting. But a four axis machine is a simple gear train like you have with most battery powered cars. A five axis machine requires two inputs to define the motion of the remaining free axis. Far as I can tell that's what the original Toyota's used. Engine + Motor1 on one input. M2 on the ring gear. Drive shaft is the remaining.

Lot of different ways to skin that cat and they can look mechanically very different.

I thought Honda mostly switched to THS-like sometime mid 200x? I know their early stuff wasn't and you could get a manual transmission Honda Civic Hybrid, but I had rwad that they switched.

Looks like Hyundai/Kia aren't though. And I wasn't able to get a good read on a lot of them. I guess I over generalized from Toyota, Honda, Ford, and Chrysler.

AFAIK there's no THS-like Honda cars. Nissan and Mazda bought THS system from Toyota and sold small amount of cars only once.
I mean, this[1] sounds like THS, mostly. I don't think THS (or Ford) use any clutches though.

[1] https://www.caranddriver.com/reviews/a15121345/honda-accord-...

It's just early i-MMD (basically series-hybrid, but also can drive directly by engine on highway) system, according to PR, despite they said "eCVT". It's confusing. They called two motor(generator) connected via electricity (but not connected mechanically) as "eCVT". It uses clutch to switch direct drive on highway. https://global.honda/newsroom/news/2013/4130620eng-accord.ht...