The problem with series hybrids

[dcb]

yup, that setup is pushing a porshe in the halfbakery thread
http://ecomodder.com/forum/showthrea...t-ev-8502.html

[bwilson4web]

Originally Posted by RobertSmalls

Yep, that's one way to make a parallel hybrid. Here's an EV with a tow-behind diesel engine mated to a three-speed automatic transmission:

http://www.mrsharkey.com/pusher.htm

Interesting but my thoughts have been to make the trailer an EV pushing our Prius for urban commuting:

• lower peak power - urban travel speeds require lower power reducing the thrust requirement.

The same logic works for existing ICE vehicles. Other than parking, an urban EV pusher makes a lot of sense. If close coupled, the parking problem is reduced.

Bob Wilson

[cfg83]

RobertSmalls -

Originally Posted by RobertSmalls

Yep, that's one way to make a parallel hybrid. Here's an EV with a tow-behind diesel engine mated to a three-speed automatic transmission:

http://www.mrsharkey.com/pusher.htm

Yeah, that's what I was thinking of. But the one in my brain is the 4th gen Honda Civic EV pusher (can't find the link).

CarloSW2

[bushi]

Originally Posted by Tweety

Again... That is stupid... You are comparing apples and oranges... Of course a hydraulic transmission beats a mechanical, every day...
But calling that a Hydraulic Hybrid is just stupid... There are no hydralic motors there as far as I can figure... The hydraulic transfer the energy from the engine to the wheel, same as the mechanical parts do on any other car...

Now the hydraulic system is very efficient, but also expensive... If you couple it with a good ICE, you get a highly efficient ICE car... Not a hybrid... If you instead drop in an electric motor, you get an insanely efficient EV, since the electric engine is much more efficient than any ICE engine... Now bear in mind my wording... I'm talking energy in in one end, to the shaft out of the engine, not well-to wheel... well-to-engine out if you will...

hello,

This is my first post here, so hello everyone

I have a question: did any of you, opponents of Hydraulic Series Hybrids, did a homework and actually read the links provided by Old Mechanic? I urge you to do so, before replying, otherwise you just expose your lack of knowledge.

Hydraulic Hybrids might very well not take off at all, despite their superiority over BOTH Electric Hybrids, AND purely ICE-propelled cars, because pendulum already shifted to electric, for many reasons, OT here. But Old Mechanic's points are 100% accurate, as you can read in the links he has provided.

Actually, Hydraulic Hybrids are the only hybrids, that would make environmental/economical sense in the transition time to fully electrics vehicles, and instantly increase the mileage 40% in combined cycles, and over 100% in urban traffic cycles, which has been PROVEN and TESTED - again, revert to Old Mechanic's links.

Please, do yourself and this forum a favor and read these articles. That is interesting reading, and will save us all arguing about FACTS that were proven/tested by a few companies, in both Europe/US, some even commercialized.

That's my 2c
[Hint: the average family sedan needs ~17KW to maintain highway speeds. If you could provide all the juice required to accelerate, say, 0-70 from accumulated compressed gas, than you'll only need an on-board ICE of similiar max power capabilities (say 20KW), and fine-tuned for specific power delivery point only. I would say that 600ccm (~37 cubic inches) displacement, working at it's "sweet spot" all the time will be well enough. Now, how is that in terms of mileage, comparing to the same average family sedan, you think?]

Regards

[user removed]

I appreciate the support bushi.

I hope all who read this understand the most important point.

My design as well as several other similar designs are for a power train that allows for precise application of engine or electric motor power to the vehicle, with the additional advantage of highly efficient recovery and reapplication of energy normally lost in deceleration and braking.

It also allows for pulse and glide operation of the engine, or electric motor, in cruising speeds.

It does not compete with battery electric vehicles. Quite the opposite, it compliments the efficiency of any primary drive system.

Even the Tesla responds to pulse and glide operation as a range extending tactic.

As long as pulse and glide improves the range of any vehicle regardless of its configuration, a power train design that allows pulse and glide operation to be incorporated into the power train itself, will reduce the amount of energy required to travel a specific distance.

There are many other advantages beyond this.

Current battery technology requires a control device to regulate the power from the battery to the electric motor for regulation of vehicle speed. This is not necessary with an on-off strategy that operates the electric motor at peak efficiency with the power produced applied to the vehicle and the accumulator depending on the acceleration required. It also allows for higher regeneration efficiencies in electric vehicles by allowing the surge of energy in higher deceleration events to be applies to the battery over a longer period of time.

This design replaces the brakes completely, eliminating that vehicle component completely. The exception is an emergency brake similar to what is used in vehicles today as a backup system, although thsi could be accomplished with a simple hydraulic lock.

Cost has been called a factor. I completely disagree with that assumption. Consider the cost of the Prius transmission and differential. Replacement cost is $8000 for that component alone.

Each in wheel drive that replaces the brakes, would only cost the manufacturer about the same to build as the brake system parts replaced. Other than that there is no "transmission". I am not trying to debate whether the Prius has a transmission or not in the traditional sense. It certainly does have a method of transmitting the power of the electric motor and gasoline engine to the driven wheels, so by that definition it has a "transmission".

Many electric vehicle advocates state that BEVs need no transmission as a means of supporting their belief that EVs are the better choice. I disagree with that belief and most EV builders realize that some form of gearing is necessary unless you want to compromise with a huge electric motor (read expensive).

The original post by dcb expressed his concerns about the cumulative losses in hybrid electric and electric vehicles. Another consideration is the extra components, beyond a conventional vehicle and their considerable cost to produce, as well as life expectancies.

Sealed unit in wheel IVT's have a cycle life measured in hundreds of thousands of cycles, possibly millions or cycles. Hybrid components in the Prius and any other vehicle that uses a battery as a prime mover can make no such claims. Gears, batteries, electric motors, DC to Ac converters, and computer controls, are all very expensive and have definite life expectancies. Many hydraulic components currently produced have life expectancies close to 10,000 hours of operational time. That's 600k miles at 60 MPH.

Modern hybrids are very complicated systems, and their complexity and cost of repair will only grow dramatically compared to conventional vehicles. 60,000 hours of working on cars has taught me one lesson. If you want to drive it into the ground and 500k miles, you need something simple. The fewer frills the better from that perspective.
That is the reason I own a Civic VX. My Insight has required $7000 in warranty repairs in the last year, before it reached 55k miles. That is twice the cost of the VX, which has been trouble free and does not even have the components that were replaced under warranty in the Insight.

Even compared to conventional vehicles the design I advocate has significantly fewer parts, and eliminates whole systems altogether. I estimated the parts content per vehicle as 25% less, and the manufacturers cost to produce as 20% less than any conventional vehicle.

You can only prove those types of claims with a lot of independent, unbiased research, or a produced example. I have neither, although that is my immediate goal.

The transition should be incremental, with a Launch assist rear axle option on an otherwise conventional small inexpensive FWD car. This would allow a significant economy benefit with a minuscule increase in cost. That is low hanging fruit, that would provide income for the future integration of the design into a dedicated hydraulic power train and regenerative storage system.

This could be done in less than two years, from today, to available on a showroom floor. The mileage improvement would be significant, in the range of 25-40%.

This could be a retro fit on something like my 94 VX, and that may be the way I go in the near future. Even the simple launch assist would allow pulse and glide when cruising at highway speeds, and the mileage improvement would be in spite of the fact that you actually have two separate power trains.

The same system would also serve as a stop start system for engine off when stopped mileage improvements, with no additional components beyond the launch assist additions.
An engine driven pump could easily serve as the starter by simply reversing the high pressure pathway valving.

We all have agendas of one type or the other. Mine is driven by many thousands of hours of research, and close to a half a century of experience driven by a love of cars that began before I could ever drive a car legally.

To this day not a single person has provided any evidence to refute my beliefs. Some of those people are highly educated with Doctorates in Engineering from nationally recognized colleges and universities, from West Point, to MIT, to Virginia Tech.

This design does not exclude or compete with the development of the electric vehicle in any way. We wait for the battery of the future today. Many researchers are also working on developing IC engines that approach 60% efficiency.

I don't know what the future holds as far as battery technology, and I don't think anyone can accurately predict the energy density, reliability, and cost of batteries in 20 years.

That's not the point. The point is this is available today for further development. It exists today, not some time in the future. It can make any currently produced vehicle less costly to produce and much more efficient.

Right now, Today, it has reached that point.

I believe in the future you will see a similar power train design applied to every vehicle on the planet. The first manufacturer that controls the patent and the rights to produce such a power train system will have a huge head start on the rest of the industry.

I hope to see it happen in my lifetime. It could improve the quality of life for billions of people who could improve their lives with simple inexpensive efficient transportation.

regards
Mech

[NeilBlanchard]

Okay, here's a serial AND parallel hybrid drive:

Green Car Congress: GETRAG to Exhibit Boosted Range Extender at METAV; Electric and Mechanical Drive

[NeilBlanchard]

Here's an interesting bit of information:

General Motors EV1 - Wikipedia, the free encyclopedia

EV1 series hybrid
EV1 series hybrid prototype at EVS-16 in Beijing, 1999

The series hybrid prototype[61] had a gas turbine engine APU placed in the trunk. A single-stage, single-shaft, recuperated gas turbine unit with a high-speed permanent-magnet AC generator was provided by Williams International; it weighed 220 lb (99.8 kg), measured 20 inches (50.8 cm) in diameter by 22 inches (55.9 cm) long and was running between 100,000 and 140,000 rpm. The turbine could run on a number of high-octane[citation needed] alternative fuels, from octane-boosted gasoline to compressed natural gas. The APU started automatically when the battery charge dropped below 40% and delivered 40 kW of electrical power, enough to achieve speeds up to 80 mph (128.8 km/h) and to return the car's 44 NiMH cells to a 50% charge level.

A fuel tank capacity of 6.5 US gal (24.6 L; 5.4 imp gal) and fuel economy of 60 mpg-US (3.9 L/100 km; 72 mpg-imp) to 100 mpg-US (2.4 L/100 km; 120 mpg-imp) in hybrid mode, depending on the driving conditions, allowed for a highway range of more than 390 miles (627.6 km). The car accelerated to 0-60 mph (96.6 km/h) in 9 seconds.

There was also a parallel hybrid version of the EV1, as well:

EV1 parallel hybrid

The parallel hybrid variant featured a de-stroked 1.3 L turbocharged DTI diesel engine (Isuzu Circle L), delivering 75 hp (56 kW), installed in the trunk along with an additional 6.5 hp (4.8 kW) DC motor/generator; the two motors drove the rear wheels through an electronically controlled transaxle. When combined with the AC induction motor which powered the front wheels, all three power units delivered a total output of 219 hp (163 kW), accelerating the car to 0-60 mph (96.6 km/h) in 7 seconds. A single tank of diesel fuel could keep the car running for 550 miles (890 km) with a fuel economy of 80 mpg-US (2.9 L/100 km; 96 mpg-imp)

If you do the MPGe calculation, the diesel's 80MPG is 72MPGe, while the serial hybrid got 60-100mpg. Hmmm.

[NeilBlanchard]

Green Car Congress: Lotus to Introduce Range Extender Engine

It weighs just 123 pounds and generates up to 35kW.

[daviidwilson]

Originally Posted by Daox

Oh, I definitely agree there. Throw enough technology (lean burn, atkinson, EGR, cylinder deactivation) into the gasser/diesel and you definitely can beat the conversion losses of a serial hybrid.

IMO all that's needed is a parallel hybrid w/ an appropriately integrated transmission to beat a series hybrid. The biggest issue IMO, also why everyone is jumping on the EV bandwagon, is that Toyota has built a huge portfolio of hybrid patents, and anyone who wants to use something remotely close to their parallel system has to license through them, and if they don't then they tend to have a subpar system in terms of vehicle efficiency, eg the smaller Honda Insight/Civic hybrids get worse mileage than the larger Prius.

[dcb]

well, we are getting into an area of patent law where the inventor is long out of the picture and a corporation is acting like an individual, which aint so, and consumers get less options.