Sneak Peek of the New Prius #5 - B mode confirmed

[Rybold]

Originally Posted by efusco

If you're coasting with your foot off the pedal you're getting about 12-15 amps of regen. If you keep your foot off the pedal and drop into B it WILL increase your regen to 30-40 amps.

BUT.....with your foot on the brake you can titrate the amount of regen up to around 100 amps AND you're not simultaneously throwing away energy like you are with B-mode (due to the forced ICE spin).

Does that make more sense?

That makes perfect sense. Thank you.

[PriusSport]

Now why do I like the dash better in my '08? I like the shifter out of the way--since you almost never use it driving. And I like the LCD screen up higher in the middle where it's viewable without moving your head.

They are already talking about CVT type transmissions in race cars. And how the manual tranny is on the way out.

Rupp has built a 100% electrical (battery)prototype Porsche 911. 0-60 mph in 7.0 secs. Single speed CVT tranny. Electricals don't need gears since full torque is achieved at 0 rpm. This is the future of race cars.

[efusco]

Originally Posted by PriusSport

Now why do I like the dash better in my '08? I like the shifter out of the way--since you almost never use it driving.

Interestingly, I use it almost constantly when driving...I shift b/w D & N a lot and that position better.

And I like the LCD screen up higher in the middle where it's viewable without moving your head.

Maybe, the LCD in our HiHy is more closely placed like the new Prius...it's really not an issue at all

[DaveinOlyWA]

ok... having a shifter that glows slightly i think is a good idea especially since it will no longer be as easily seen in its new position... i wonder if the higher glow factor for other controls like steering wheel and driver door will be "glowing?"

[ronhowell]

Originally Posted by efusco

If you're coasting with your foot off the pedal you're getting about 12-15 amps of regen. If you keep your foot off the pedal and drop into B it WILL increase your regen to 30-40 amps.

BUT.....with your foot on the brake you can titrate the amount of regen up to around 100 amps AND you're not simultaneously throwing away energy like you are with B-mode (due to the forced ICE spin).

Does that make more sense?

I agree Evan, it does make perfect sense. Except for the fact that any re-gen carried out at higher amperage current flows is inherently inefficient, due to the power losses in the circuitry, which shows up as heat. And 100 amps will certainly generate heat. Remember the power losses are proportional to I*2xR, where I = current and R = resistance.

So gentle braking is always more efficient. Also when using "B" mode going down a long hill, presumably the current flow eventually tapers to zero when the traction battery is fully charged. At this point, braking drag is then due solely to ICE pumping supplemented by Friction (brake pad) braking as necessary. Or am I missing something?

Ron.

[efusco]

Originally Posted by ronhowell

I agree Evan, it does make perfect sense. Except for the fact that any re-gen carried out at higher amperage current flows is inherently inefficient, due to the power losses in the circuitry, which shows up as heat. And 100 amps will certainly generate heat. Remember the power losses are proportional to I*2xR, where I = current and R = resistance.

True, that's why I always aim for the 60amp braking range...something shown to be most efficient. The question is though, what's more efficient when going down a hill...using the brakes or using B-mode....and even factoring in the heat generated and efficiency losses regen braking w/o B-mode is more efficient.

Also when using "B" mode going down a long hill, presumably the current flow eventually tapers to zero when the traction battery is fully charged. At this point, braking drag is then due solely to ICE pumping supplemented by Friction (brake pad) braking as necessary. Or am I missing something?

Ron.

Only that the battery will get full the same way using the brakes and you can then choose whether to suffer a little friction brake wear or you still have the option of B-mode sans regen.

[patsparks]

I use B if I hit the top of one particular hill with a near full battery (not green but near green) because I know at the bottom of the hill I will either be 20km/h over the speed limit and the ICE will be spinning at the next traffic lights anyway, or I'll be riding the brakes for the last two thirds of the descent, a full battery for the last third and still have the ICE spinning at the next traffic lights.
If I use B mode once the car is 3 or 4 km/h over the 80km/h speed limit I arrive at the next lights without using the brakes, the battery is full and green and the ICE might spin for a few seconds after I stop.

This hill isn't all that high but is fairly steep, it is about 2km top to bottom, has a speed limit of 80km/h at the top but just as it levels out at the bottom the speed limit drops to 70km/h.

That new interior is growing on me.

[efusco]

Originally Posted by patsparks

I use B if I hit the top of one particular hill with a near full battery (not green but near green) because I know at the bottom of the hill I will either be 20km/h over the speed limit and the ICE will be spinning at the next traffic lights anyway, or I'll be riding the brakes for the last two thirds of the descent, a full battery for the last third and still have the ICE spinning at the next traffic lights.
If I use B mode once the car is 3 or 4 km/h over the 80km/h speed limit I arrive at the next lights without using the brakes, the battery is full and green and the ICE might spin for a few seconds after I stop.

This hill isn't all that high but is fairly steep, it is about 2km top to bottom, has a speed limit of 80km/h at the top but just as it levels out at the bottom the speed limit drops to 70km/h.

That new interior is growing on me.

And that's fine, and going down a very long steep mountain it's a reasonable option without any real drawbacks. But it never offers any significant advantages either.

[john1701a]

Guess where #6 is...

This new photo was well worth the wait!

It's pretty sweet !!!

.

[spwolf]

Originally Posted by john1701a

Guess where #6 is...

This new photo was well worth the wait!

It's pretty sweet !!!

.

would be so much more useful if you posted the link, now I have to look around