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How do you get maximum regenerative braking?

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This forum seems to be mostly 2013 FFH and my experience is with the 2010. Many of the principles and operation are identical and are common to all the eCVT hybrids but I don't profess to know everything about a car I don't have. There is probably nothing wrong with most of the 2013's with the exception of acdii's 2013 not doing as well as his 2010. That is puzzling. The only thing that I am considering is that the smaller, lighter 2013 ICE is run even less than the 2010 and is difficult to keep warm in the cold. All hybrids have this problem but Ford shuts down the ICE more often than anybody. With the new LiIon battery, they probably load up the ICE with charging load even more when it's running which is actually the objective to only run the ICE when it is well loaded and the BSFC is at a minimum. All vehicles have a bad cold weather penalty and it takes the same energy in any vehicle to keep everything warm. That energy is a much higher percent in a hybrid and the reduction in mpg is much greater. Pray for spring, dry roads, calm winds and summer fuel. I can loiter around town here in the south in spring and fall and coax 70 mpg by P & G ing the 2010. I expect the 2013 to do the same.

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I HATE MY Touchpad

 

Had just about finished typing a response and my paml touched it and sent me back a page! ARRGGHHH

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Trying this again

 

lolder hit it on the head. I am pretty much convinced the problems I have with mine relate directly with the cooling system. Once someone mentioned that the engine may be running cold I focused my attention to the engine temps on the Scangauge, and sure enough, during my daily commute they pretty much stayed below 170*, way too cold to get a good burn, which would also explain the plug fouling.

 

When I mentioned this to my service manager and the Ford engineer it drew blank stares, and shrugs, and the ubiquitous we see nothing wrong. I asked about the shutters and found their expensive computer has no diagnostics for the shutter system so unless they visually look at them at highway speeds, they have no idea of they are open or closed.

 

In the 2010 it sits right at 190* and gets there quickly too. In half the distance it takes the 13 to get to 160* the 10 is at 190*. However, when I mention this to Ford, their corporate response is, the 2013 is nothing like the 2010. I see, so the technology of the 13 is so far different than any other car out there in that it can get a complete fuel burn at 160* where in any other car it needs to be near 200* or better.

 

And now you know MY frustration!

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Can someone elaborate on "ICE" and "EV" I assume ICE is the gasoline engine, and EV is the battery? What does ICE stand for ?

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Can someone elaborate on "ICE" and "EV" I assume ICE is the gasoline engine, and EV is the battery? What does ICE stand for ?

 

ICE - Internal Combustion Engine

EV - Electric Vehicle (mode)

HVB - High Voltage Battery

SOC - State of Charge

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Quick question on accelerating, I have played with many of the 'My View' configurations, one by using the RPM display. Has anyone found a good general limit for accelerating from a stop to say 40mph?

 

Like a max of 2,000 or 3,000 then dropping into EV mode?

Flat surface of course, and assuming the engine is warmed up.

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On the braking, I have noticed that if I used the Adaptive Cruise, and someone cuts in front of me, or traffic slows really quick, my car can slow down (on its own – I don’t touch the brake) from 60+ to 10mph very fast. I always assume this is only using the regen braking. But maybe I am wrong.

Any opinions on this? If it’s using only the regen braking, then is it charging at a higher rate because of the fast braking effect? In other words, generating more charge due to the harder regen action?

Or is it actually using the friction brakes as well as the regen?

I would love to learn the limit where it goes to friction. But maybe only the computer can max out the regen braking, and won’t do that when the driver is using the brake pedal.

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Regarding the acceleration I would guess ask 10 different people and you 10 different suggestions.

For me at all depends on the situation I try to stay below or around the 2nd white bar on the empower screen don't ask me what the rev's are I simply never looked at it.

Now while you are accelerating look a the instant MPG it appears there is a range of power demand where the MPGs don't change much during accel.

 

Now my 2 cents about the braking; I don't have ACC but just by using the brakes manually I can see the difference in the brake score between slow and steady or fast and hard braking.

Yes you generate the energy faster braking harder but can you store it as fast? I don't think so because if this would be the case a brake score of 100% should always be possible.

 

I think there is certain rate you can store the energy back into the battery if you exceed the rate it will use the friction brakes for the excess energy or it discharged otherwise. I have never heard of a braking resitor being used in a car to bleed of the excess energy so I guess it goes into the friction brakes.

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Corncobs,

Good info. In driving to work this morning I was watching the bars, and I agree that staying below or inside the second bar (of the 5) is a good rule. Seems the hardest time to get mileage is first thing in the morning. Even at 70 degrees outside, the engine needs to warm up I guess.

But also this morning my EV battery was almost gone so it had to charge also. Got it half way up pretty quick.

My drive to work is just under 2 miles, so a very short distance. Trying to make those trips high MPG but not easy.

 

Anyway, good points.

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On the braking, I have noticed that if I used the Adaptive Cruise, and someone cuts in front of me, or traffic slows really quick, my car can slow down (on its own – I don’t touch the brake) from 60+ to 10mph very fast. I always assume this is only using the regen braking. But maybe I am wrong.

Any opinions on this? If it’s using only the regen braking, then is it charging at a higher rate because of the fast braking effect? In other words, generating more charge due to the harder regen action?

Or is it actually using the friction brakes as well as the regen?

I would love to learn the limit where it goes to friction. But maybe only the computer can max out the regen braking, and won’t do that when the driver is using the brake pedal.

I'm pretty sure the car will use both regen and friction brakes when it stops that fast. What really bugs me is when someone in front of me turns and I can see them driving away from my lane, but my car keeps slowing down! It takes a lot of energy to get back to cruising speed and the ICE engine usually kicks in ... when it could've slowed down less and just kept on cruising, but get a little closer to the car in front of me :)

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There are four settings for the gap between the two cars. Which one are you using?

Sporty (1 second), Normal (1.5 seconds), Normal (1.9 seconds), Comfort (2.3 seconds).

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There are four settings for the gap between the two cars. Which one are you using?

Sporty (1 second), Normal (1.5 seconds), Normal (1.9 seconds), Comfort (2.3 seconds).

I set it to 1s in the city or 1.5s/1.9s on the highway. I tried increasing it to 1.5s in the city and it didn't seem to make a difference. Maybe I just drive aggressively and like to cut it close :-)

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I'm pretty sure the car will use both regen and friction brakes when it stops that fast. What really bugs me is when someone in front of me turns and I can see them driving away from my lane, but my car keeps slowing down! It takes a lot of energy to get back to cruising speed and the ICE engine usually kicks in ... when it could've slowed down less and just kept on cruising, but get a little closer to the car in front of me :)

 

I agree but then sometimes if someone cuts in front of me but is going faster (moving away from me) it works just fine. Like the car knows and doesn't slow down. But then sometimes it doesn't do that, and slows down, the car moves accross my lane into another lane, no one is in front of me at all and the car continues to slow down another couple of seconds before releasing. That bugs!!! But can't be perfect I suppose :)

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As for my Gap settings I change it all the time. Normally I like two bars, but on the freeway if I see a big truck, I get behind it and set to one bar to draft. I get lots of EV that way if the truck is under 65mph. Like that.

 

But if I see traffic building up ahead, I go 4 bars to increase distance and allow more automated speed. I don't have to interveine with brakes as much this way.

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As for my Gap settings I change it all the time. Normally I like two bars, but on the freeway if I see a big truck, I get behind it and set to one bar to draft. I get lots of EV that way if the truck is under 65mph. Like that.

 

But if I see traffic building up ahead, I go 4 bars to increase distance and allow more automated speed. I don't have to interveine with brakes as much this way.

I tried the 1 bar approach behind a truck, the driver got pissed and played games, so I keep it at 2 bars and still do very good. I found that if you can get behind a flatbed and set it at 2 bars, I get the best highway mileage. WHen I had the Pious I got 75 MPG doing this.

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I tried the 1 bar approach behind a truck, the driver got pissed and played games, so I keep it at 2 bars and still do very good. I found that if you can get behind a flatbed and set it at 2 bars, I get the best highway mileage. WHen I had the Pious I got 75 MPG doing this.

 

lol. Bad Truck Driver !!!

 

-- Looking for flatbeds now --

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I tried the 1 bar approach behind a truck, the driver got pissed and played games, so I keep it at 2 bars and still do very good. I found that if you can get behind a flatbed and set it at 2 bars, I get the best highway mileage. WHen I had the Pious I got 75 MPG doing this.

You are lucky he didn't test his underride guard on you.

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No nothing like that, He sped up and slowed down a lot. I follow the rule of if I can see his mirror I am far enough behind, yet close enough to benefit.

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I find the tach display useless on a continuously variable engine. It's more useful on a standard car with multiple gears. On a continuous varlable engine, the power display is more useful.

 

I started out using the Empower display to see where the EV is relative to the max EV box. I've recently been paying attention to the Engage display that shows the ICE and EV graphs side-by-side, especially when in adaptive cruise control. It's interesting to see when the car uses the EV to boost the ICE.

 

The only thing that you don't get on Engage is the EV limit indicator before the ICE takes over. From practice and experience, it seems that the EV disengages at the half-way point on the Engage display, but will use the whole range when in EV+ mode.

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I try to stay as far awy from trucks as possible to avoid the rocks they toss up. I already have a really tiny chip in the windshield from a semi

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Getting the car up to speed from a dead stop uses a lot of energy. The proven method is to use the engine to accelerate to speed and then release the throttle and then reapply to get it to switch to electric mode to maintain that speed, assuming you are not climbing a hill.

 

At 0mph an ICE has zero torque, where as an electric motor has 100% torque the instant it gets juice. This means overall from a stop, you use your energy more efficiently to start in EV mode.

 

What I find most effective, and the coach agrees, start out rolling on EV for about 5-7 MPH and let the ICE kick in. When you do it right you wont even feel the ICE spin up. What it doesn't like is hitting the throttle from a dead stop, it will drop that bar faster than Congress voting on an unread bill. However accelerating on EV only up to say 30 MPH does waste fuel because now you have to recharge the batteries with the ICE, and that is where the gas gets wasted. Go read the thread accelerating under the Hybrid tricks forum.

 

I will typically try to stay in EV mode up to at least 15mph, but yes it is best to come off a complete stop in EV mode. I don't know where the best point is to switch over to ICE, but in general just to keep Bubba from pushing you off the road you need to switch over to ICE at some point to improve acceleration.

 

 

On the braking, I have noticed that if I used the Adaptive Cruise, and someone cuts in front of me, or traffic slows really quick, my car can slow down (on its own – I don’t touch the brake) from 60+ to 10mph very fast. I always assume this is only using the regen braking. But maybe I am wrong.

Any opinions on this? If it’s using only the regen braking, then is it charging at a higher rate because of the fast braking effect? In other words, generating more charge due to the harder regen action?

Or is it actually using the friction brakes as well as the regen?

I would love to learn the limit where it goes to friction. But maybe only the computer can max out the regen braking, and won’t do that when the driver is using the brake pedal.

 

Adaptive Cruise Control has a habit of kicking in friction brakes if it thinks it needs to slow down really quick. This is one reason I really wish there was a three second following distance option. One thing I learned from my days of commercial driving is that if you are having to apply the brakes frequently to adjust for the speed of drivers in front of you, you are following too damn close. With a proper following distance, you can simply let off the accelerator and drift to a slower speed to adjust for minor traffic changes ahead.

 

 

I'm pretty sure the car will use both regen and friction brakes when it stops that fast. What really bugs me is when someone in front of me turns and I can see them driving away from my lane, but my car keeps slowing down! It takes a lot of energy to get back to cruising speed and the ICE engine usually kicks in ... when it could've slowed down less and just kept on cruising, but get a little closer to the car in front of me :)

 

Ya I find that a bit annoying as well, but if I see it is going to happen, I temporary cancel cruise control and apply the proper amount of breaking to adjust for the turning vehicle.

 

There are four settings for the gap between the two cars. Which one are you using?

Sporty (1 second), Normal (1.5 seconds), Normal (1.9 seconds), Comfort (2.3 seconds).

 

Thanks, I never new what the bars represented. I really wish there was at least a fifth bar for 3 seconds. This would give the adaptive cruise control more space to more gradually adjust for changes in speed by the leading vehicle.

 

In all truthfulness from a safe driving perspective the ideal following distance is never less than two seconds. Anyone following at one second is asking to eat the bumper in front of them.

 

I tried the 1 bar approach behind a truck, the driver got pissed and played games, so I keep it at 2 bars and still do very good. I found that if you can get behind a flatbed and set it at 2 bars, I get the best highway mileage. WHen I had the Pious I got 75 MPG doing this.

 

One bar is fullish and it makes truck drivers really nervous. I don't think they realize you have automated systems that will adjust your vehicle speed to whatever they are doing. What they are envisioning is that a moment of inattention on your part will cause you to ride up under their rear bumper causing a serious accident.

 

Even at two bars you really don't have time to react if one of the truck's tires start shredding (I've had it happen).

 

I try to stay as far awy from trucks as possible to avoid the rocks they toss up. I already have a really tiny chip in the windshield from a semi

Ya nothing will destroy the front paint job or windshield faster than road debris or shredding truck tires.

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At 0mph an ICE has zero torque, where as an electric motor has 100% torque the instant it gets juice.

Is that right??? :headscratch:

Just a question on this. To clarify my thoughts.

 

When ever I start any elec motor.

There is a starting lag. A ramp up to speed and then there is the max running momentum creating max torque. Not 100% torque at juice time.

It's torque is much faster than any gas engine drivetrain. MY point is that its more like 1-3 seconds. Closer to 60%+ at juiced.

 

Gas engines running do have torque, It's just pissed away in the torque converter.

Awaiting adequate pressure to force rotation. But it will hold you in place on a small hill.

 

 

I will typically try to stay in EV mode up to at least 15mph, but yes it is best to come off a complete stop in EV mode. I don't know where the best point is to switch over to ICE, but in general just to keep Bubba from pushing you off the road you need to switch over to ICE at some point to improve acceleration.

 

 

I believe that electric start method is the best way to increase your overall MPG's.

But the load on the car determines the best point of transition to gas engine. (Going uphill for example takes much more torque)

So, it's always variable.

 

I agree about the 15 mph switch over in practice. It seems to match my experiences so far. If I do trip on the ICE. I use it to get quickly to cruising speed. Then let the elec take back over.

 

Sure would like to find a better way.

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Yes that is right. Electric motors have very high torque at 0 rpm.

 

http://www.engineeringtoolbox.com/electrical-motors-torques-d_651.html

In addition to this link we are also talking about an PMSM motor which does have a so called holding torque which is the max torque of the motor as soon you apply power.

With AC motors is a bit different like the curve on the link shows. PMSM motors have their max torque at a designed speed that's why the torque increases as speed increases.

 

PMSM = Permanent Magnet Synchronous Motor still AC not DC

Edited by corncobs

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