What did we learn from the Chief Engineer?

Congratulations are due Toyota for their insight to invite PC leaders to view and react. The reviews have been great.
Thanks guys!

 

OP quote: "7. The max rpm went from 10000 to 13500, but was unclear what max EV mode speed was or if top end speed was raised to higher than 115???"

I'm not ready to give up hope on higher EV glide. No good reason to permit 13500 if not for ICE shut down at higher speed than before. I think the test mule xcel drove had the higher speed glide from this change. Anyone worked out the PSD math on what 13500 would mean?

 

yeah, you will be able to customize it... and you should be able to customize other things as well

 

I'm not sure you can compare to the current model at all. It sounds like the PSD is significantly altered, so all bets are off. I would assume the relationship between wheel speed and MG2 rpms (with ICE 0 rpm) is related to the relative size of the gears in between. Since those gears may have changed, its impossible to know what the new relationship is. That doesn't rule out the possibility of higher speed EV, but says we don't know.

Rob

 

You are exactly right. With the language issues, I just don't know.

Found the Gen II formulae: MG1 = 3.6 x ICE - 2.6 x MG2
MG2 = 59.1 x mph
Gen II limits: mg1 +-6500, mg2 6000, ice 4500
Haven't seen any Gen III constants and john1701a mentioned mg2 was 2-speed now or something like that.

 

That is a good thing

I like that one too.

Not so sure that is a good thing AT ALL. Not that having the middle person straddle the 'hump' on the current model is exactly ideal, but it looks like they now also have to contend with their legs hitting the front console. Other than a kid in a booster seat, or a very short adult, it appears to pretty much turn the car into a 4 passenger.

ie. "Not recommended"

Good plan, as I can not currently ride in the back without heading my head on the glass. Of course, I'm the dad, I don't HAVE to ride in the back It doesn't hurt that the taller of my daughters probably won't make 5'6" so no problem there. I (very un-fondly) remember cramming into the back of my step-father's 1970's era Datsun (for you youngin's, that was before they became Nissan).

I guess that is OK but i never found it a problem to pull them out when I wanted to fold the front seat back flat. It still does that, RIGHT ??????

I always wondered why this wasn't done on the Gen II given the desire to reduce Cd. Seemed an oversight.

 

Oh, dear. What is the chief engineer's name? Please? I'm labeling photos...

 

Akihiko Otsuka

.

 

Gesundheit!

 

Correct and correct. I asked about the reduction gear but I understood the answer no further than the Chief Engineer's promise that it provided higher efficiency. That was good enough for me.

How about that Chief? I could not believe his patience with fools like myself. He also was willing to answer any question at all and could not have been more gracious.

 

All of my photos and my three videos are posted now.
Please, feel free to comment and tell me when I mess up people's names, okay?
Thank you!

 

i agree, what a nice guy. he had to be tired also, from the mornings unveiling and his trip over from Japan to dealing with all of us.......

 

My recollection from when the 2-speed came out on the Camry is that one of the benefits is a big improvement in regen efficiency. The higher the rpm of the generator, the higher its output voltage, and the more current the inverter can put back into the battery. As you slow down, voltage naturally drops of quickly. With a higher gear ratio available, voltage stays higher longer, and more energy can be recovered during braking. Am I remembering correctly that this was one of the advertised benefits of the 2-speed?

Rob

 

Similarly, you want a low gear ratio from MG2 to the wheels to put as much torque on the ground as possible at low speed, but as rpms go up, the motor's naturally generated voltage (back EMF) fights against the inverter reducing the effectiveness of the electric drive. In the 2G PSD you have to compromise between these two with a single gear ratio, although they did also add the boost converter to up the output voltage and increase the effective rpm range over the 1G. The 2-speed should allow you to put more torque to the wheels at low speeds, and reduce rpms at high speed so you get more power there too. Sounds pretty good!

Rob

 

I've never studied the Camry/HH/Lexus system, but here's the kind of thing I remember (from john1701a's blog)

"11-30-2007 Multi-Stage Hybrid. Camry-Hybrid differs from Prius by having a second PSD. The purpose is to enable delivery of a second speed, much like gearing"

I thought I had heard several indications that the new Prius system was essentially the same, so I guess I assumed that meant effectively two-speeds. Not sure if that was a correct assumption or not.

Rob