Regeneration choices
#2
12-29-2007, 05:51 PM
Re: Regeneration choices
No. The regeneration of power from most to least is as follows:
1. Engine Braking
2. Light Braking
3. Coasting to a stop
1. Engine Braking
2. Light Braking
3. Coasting to a stop
#4
12-30-2007, 02:22 AM
Join Date: Nov 2007
Location: New Jersey
Posts: 2,051
Re: Regeneration choices
Both 'D' and 'B' modes regenerate energy to the battery, provided the battery isn't "full." It's just that 'B' mode does more of it — it gives more braking effect, some of which is regenerative, and some of which is true "engine braking." Also, once the battery is "full," neither mode will regenerate at all. In 'D' mode, all braking will be by the (lossy) friction brakes; whereas in 'B' mode, the ICE will be spun by the wheels (via the two motor-generators) to give (lossy) engine braking. So, with the battery "full," all braking is lossy.
Stan
Stan
Last edited by haroldo; 01-04-2008 at 07:25 AM.
#5
12-30-2007, 06:44 AM
Re: Regeneration choices
All the statements are consistent except for your "does not regenerate while coasting". "Engine braking" is done by spinning up the ICE both in the TCH and in conventional cars. This absorbs energy, but does not regenerate. "Coasting to a stop" would be the condition where the foot is off the accelerator and speed is being lost. This regenerates in the TCH to mimic the effect of engine braking in an automatic transmission-equipped car in "D", however there is no engine braking -- indeed the ICE isn't necessarily spinning.
The only real engine braking occurs when in "B", engine braking is simulated when coasting, and friction braking is simulated under "light braking". Only the latter two regenerate.
The only real engine braking occurs when in "B", engine braking is simulated when coasting, and friction braking is simulated under "light braking". Only the latter two regenerate.
#6
12-30-2007, 06:47 AM
Re: Regeneration choices
Compared to my previous '04 Prius coasting produces very little regereration. I've coast down LONG hills with the battery not fully charged and haven't even gotten one "Car" on the energy display (I have a NAV what gives you Energy Displays).
The Prius would slow down 1 miles per hour/sec no matter what the downgrade was. The Camry will accelerate a LOT on even moderate downhills. This leads me to believe there is LITTLE regen done just coasting even though the energy screen show the arrows going TO the battery.
The Prius would slow down 1 miles per hour/sec no matter what the downgrade was. The Camry will accelerate a LOT on even moderate downhills. This leads me to believe there is LITTLE regen done just coasting even though the energy screen show the arrows going TO the battery.
Last edited by schmidtj; 12-30-2007 at 03:22 PM.
#7
12-30-2007, 11:08 AM
Re: Regeneration choices
Compared to my previous '04 Prius coasting produces very little regereration. I've coasted down LONG hills with the battery not fully charged and haven't even gotten one "Leaf" on the energy display (I have a NAV what gives you Energy Displays).
The Prius would slow down 1 miles per hour/sec no matter what the downgrade was. The Camry will accelerate a LOT on moderate downhills. This leads me to believe there is LITTLE regen done just coasting even though the energy screen show the arrows going TO the battery.
The Prius would slow down 1 miles per hour/sec no matter what the downgrade was. The Camry will accelerate a LOT on moderate downhills. This leads me to believe there is LITTLE regen done just coasting even though the energy screen show the arrows going TO the battery.
My guess is that Toyota set up the TCH differently on purpose, calibrating the amount of regen-braking that would happen without using the brake pedal so that the TCH has a similar coasting behavior to non-hybrid cars with automatic transmissions. I'd bet that Toyota has an overall strategy in the TCH design to make it a "stealth" hybrid, or one where the hybrid nature of the vehicle is transparent to the driver, in order to sell more of them to folks that are really just looking for a Camry with good economy, rather than only hybrid buyers.
#8
12-30-2007, 12:38 PM
Re: Regeneration choices
The TCH does regenerate power while coasting, look at the energy screen after coasting down a long grade and you will see a little car on one of the bars on the bar graph. The little car represents the amount of power regenerated.
The TCH is much heavier than the Prius, therefore you won't notice the regeneration drag as much but it does regenerate power while coasting.
The TCH is much heavier than the Prius, therefore you won't notice the regeneration drag as much but it does regenerate power while coasting.
#9
12-30-2007, 01:46 PM
Re: Regeneration choices
The TCH does regenerate power while coasting, look at the energy screen after coasting down a long grade and you will see a little car on one of the bars on the bar graph. The little car represents the amount of power regenerated.
The TCH is much heavier than the Prius, therefore you won't notice the regeneration drag as much but it does regenerate power while coasting.
The TCH is much heavier than the Prius, therefore you won't notice the regeneration drag as much but it does regenerate power while coasting.
#10
12-30-2007, 02:32 PM
Re: Regeneration choices
My TCH doesn't have the NAV, but I did see the regen symbols on the Prius I rented. Are the regen symbols on the TCH the same amount of energy each as the Prius? If not, that could account for the difference.
