Hi All

It was RandyKato that brought up the fact that the elec motor powers the FEH at first while the oil get circulated. It does this when the engine is hot also if it has been off for more than a few minutes. This program that may have to be alterred if we had a battery that would carry us longer than the present system.

With regard to the creep mode, among other things it serves as a hold on a hill if you let off the brake to accelerate. It will roll back, but you stand a better chance from rolling into the front of the vehicle behind you.

Torque control strategy for management of creep and grade hold torque in a wheeled vehicle whose powertrain includes a rotary electric machine
http://www.freepatentsonline.com/6278916.html

The present invention relates to a torque control strategy for management of regenerative braking that comprises novel inter-relationships between a PCM and a BCU. The inventive principles provide a comprehensive torque control strategy that includes a sub-strategy for grade hold and creep torque management. It is believed that the inventive principles can contribute to improved overall operating efficiency of an electric vehicle while maintaining grade hold capability.

Now that I have the FEH and studied its design for almost two years, Ford's engineering team did a great job all in all. Ford has been losing money on the FEH, what more could you ask for?

GaryG

 

I think we each have our wishes that the FEH could perform better for each of our individual needs and driving routines, but they obviously had to strike a balance. And for what the FEH is, and is intended to be, I think it's quite remarkable.

The green aspect of this vehicle is not only to reduce gasoline usage, but more importantly it's to reduce emissions. These two go hand in hand... to a point. If the system weren't programmed to get the catalyst up to operating temperature, and keep it there, the gas savings might benefit slightly, but the emissions would go way up in some cases.

 

Yeah... I discovered this effect pretty early on, and restated this on a recent thread.

In EV mode, the battery must hold enough "wattage" in reserve to start the gas engine when called for. Thus, you have reduced accelration in EV mode.

IN EV MODE:
Total battery wattage minus engine startup wattage = acceleration wattage.
( ballpark figure: 15,000 watts )

Once the gas engine is running, #1 the battery does not have to "hold back" that reserve, and #2 the gas engine can spin the generator and provide extra wattage to the traction motor, that spins the wheels.

ICE RUNNING MODE:
Total battery wattage plus generator wattage = acceleration wattage.
( ballpark figure: 50,000 watts )

-John

 

I found the ratings... the generator is 36kW, the battery (NEW) can provide 39kW, the motor can consume 65kW... so to drive that motor at full power you need to pull from the battery and generator at the same time. The battery can only take it a litte over 55% of its rating. So then engine would have to come on.

http://www.motorcraftservice.com/vdi...DSM600_HEV.pdf

Of course since the ratings for the generator and battery are pretty close... it kind of kills my one arrow might be a much larger scale theory.

 

So what I'm hearing is that there's hope for current FEH/MMH to have decent EV acceleration if only battery technology can improve by about 3x (power output per weight ratio), to allow for both ICE starts, and ~50kw acceleration. THAT would be a worthwile improvement.

My wife's commute is only ~4miles, and she rarely go pass 40mph. Wouldnt be a hoot if she can do all EV with normal acelleration and plug in to recharge at night!... 4c/mile electricity cost, 32c/day commute, $1.50/week, ~$75/year commute! Heck in 5yrs, that could save well over $5k....a $5k conversion kit I would buy!

 

Maybe, however don't get confused... in this case its not energy capacity its available current and those don't necessarily go up together, though they can. Of course the capacity would have to go up too or you'd just drain your battery three times faster (and it doesn't go far now). However its hard to say how the contolling hardware that shuffles the current around is built internally (I'm very hazy on how this part works, but if it is swiching current from one circuit to another it might not be built to handle 3x the current from the battery and that would have to be replaced as well. And who knows if the wires from the back to the front are sized correctly for that much current (they are pretty darn big though).

Its pretty possible that so many things would have to be changed to handle the new current that you'd essentially have to gut alot of the system out and it would be very cost prohibitive.

I personally would not get my hopes up for any kind of an aftermarket thing to do this.

 

Hi All

There have been some good points raised here, but changing programs in the FEH/MMH is a little over our heads. Bigger, longer lasting batteries require bigger and better motors. This in turn causes increased cooling of the electronics and so forth. Going longer in EV causes the CAT and engine to cool down and then you have problems with emissions and poor performance.

Right now, I'm pushing the FWD FEH to its limits in EV with the stock system while trying not to damage anything. Here in South Florida it is still hot (90F today), and I'm at around 45mpg with 550 miles on my tank right now. When it cool down here, I expect to push some 55mpg plus tanks. What I'm trying to say is, where there is a will , there is away. If you think about it, you people in very cold weather can make adjustments to your FEH/MMH to improve mileage. For instance, what about plugging the vent to the HV battery on the outside and letting the warm air in the cabin in by removing the cover and filter. You can still place filtering material between the cabin and the duct. This could allow your battery to stay in an ideal temp range for the best performance. There should not be any toxic or corrosive gases to be concerned about? Any idea's.

Here is an article you my want to read:
http://calcars.org/calcars-news/412.html

When it comes to hybrids at Ford Motor Co., Tom Watson is the man
behind the curtain. As manager of hybrid propulsion systems, he
supervises 350 engineers who design and tune the components and write
the software that runs the hybrid powertrain.

He spoke with Staff Reporter Richard Truett.

Is it a foregone conclusion that lithium-ion batteries will replace
nickel-metal hydride batteries someday?
Watson: I think it is. Because the benefits that it provides are just
too overwhelmingly positive to pass up on. There's less weight,
greater power density and, eventually, lower cost. We think that in
the long term that when you look at the cost-efficiency curve,
lithium ion has much better potential than nickel metal.

What keeps lithium ion out of hybrid vehicles now?
Watson: It's a matter of readiness. Historically, nickel-metal
hydride's chemical formulations for batteries for
consumer-electronics purposes are very similar to the formulation
required for automotive use. We did some tweaking on the cells that
are in the Escape Hybrid, but by and large they are very similar. So
we could take advantage of the economies of scale the traditional
manufacturing process had in place for consumer electronics. Lithium
ion hasn't always been that way. So at the same time the lithium-ion
industry has been trying to resolve some of the historical issues
with batteries, it's also had to struggle with how to get economies
of scale. The formulation of lithium ion is converging for consumer
electronics and automotive use.

Any predictions when hybrids will appear with lithium-ion batteries?
Watson: By the end of the decade.

Would the performance of an Escape Hybrid differ much with a
lithium-ion battery pack?
Watson: Our goal would be to design an equivalent power level in the
battery pack to provide an equivalent level of performance to the
nickel-metal hydride. That way we could take advantage of the weight
and cost efficiencies that come with lithium ion.

So if you could achieve the same power with fewer batteries, you
could save money.
Watson: Absolutely. We are not making money on hybrids today. And
this is one step toward our affordability.

Are there any battery breakthroughs that would make a pure electric
vehicle practical?
Watson: Well, certainly fast-charge, which some of the battery
suppliers have been touting, is a step toward that. Higher power
density, so that you are not carrying around such a burden in weight.
We have been looking at higher energy storage in a hybrid, as opposed
to just a pure EV (electric vehicle). What we are finding is that
there is not a business equation there -- that if you try to trade to
a long driving range by having a much larger energy-storage battery,
you are carrying extra weight, you are essentially building back up
two complete powertrains in a vehicle. So not only does your battery
energy storage get bigger, but you have to put bigger motors in the
transmission to be able to (get) more sustained electric driving,
unless all your electric driving is going to be below 20 mph.

Is this why plug-in hybrids don't make much sense?
Watson: Exactly.

Is there a future for plug-in hybrids?
Watson: I do see a future for plug-in hybrids, but I am not sure the
United States is the market for them. If you take a city center like
Paris, or Beijing or Shanghai, the business equation might be
different. But certainly with the cost of carrying around a full
powertrain and the cost of carrying around a fully capable EV
battery, it is a very expensive proposition. At the same time, we
have to clearly investigate the cost of the energy going into the
battery. You have to look at what the sources of the energy are for
producing electricity 24 hours a day.

GaryG

 

Gary, good post, but it's good form to cite your source -- eg. the print publication or website that originally published the material you're quoting, assuming the text was not from an interview you personally performed.

/copyright stickler

 

Hi Shannon

The link I provided shows the full article. I shorten it up for my post though.

GaryG

 

Ack! I feel like a heel... I see the link now. Don't know how in the world I missed it upon the first reading. Sorry 'bout that!