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What if we could take our non hybrid car, install a trailer hitch, plug an electrically driven 5th wheel into it, throw some batteries in the trunk, mount a hand throttle in a convenient spot near the drivers seat, and have a mild hybrid that can drive from 0-30 MPH with plug in recharging. Regenerative braking would be a plus to extend range. 0-45 MPH should be possible, on a light car like the Insight.
The Prius with the stealth mode, and ev switch have that feature, but with the heavy car, and big motors, range is again a matter of battery capacity.
The insight is so light and slippery that even with the boost batteries and 5th wheel it remains easy to push, and without sacrificing the range advantages of the Hybrid, I have an EV up to 30 MPH.
It is soooo much fun to cruise down the main street with the electric whine sounding like a landing flying saucer.
The removal of the muffler to make room for the wheel actually makes the car sound cooler.The deep put put sound reminds me of some European sports cars that I have driven in the past.
The loudness is directly proportional to engine load, and can replace the MPG display as a MPG feedback.
I wish the e-tek motors were easier to find, as it seems to be a nice performer for the 22 lbs of weight it adds. The mechanical system is fairly simple now that things have been fitted once and we know that it works, we could have a 5th wheel kit so more Insight owners could play with the concept.
The any car 5th EV wheel would take some more prototype work as the motor/wheel system would have to follow the car like a trailer, so it would need a special attachment device. To make this mount universal so it would fit many vehicle styles would take some tinkering as well.
What a difference that could make, people exposed to heavy stop and go traffic could get infinite MPG while driving in the city. That alone could raise the average MPG of the American fleet substantially.
The size of the system would not be restrained like it is on the Insight, so one could have a big unit for vans and pickup trucks, and add battery capacity if the commute is long. When the van is dead, move your e-booster 5thwheel to your new Van, and off you go.
Very interesting set of possibilities.
:) ;)

Imagining one of those trailers on the VX.............:D :D :D

the 5th wheel has some nice advantages over some of the other options for most cars...

for instance trying to attach to the drive shaft of most cars is tricky at best and doing so in the limited space of the Insight's front drive shaft is even tricker....

Compaired to a wheel motor the 5th wheel does not have to add nearly as much if any unsprung weight to the car.

The Direct Electric motor to wheel connection used should give the EV-Mode / stealth mode of the prius or HCH06 a run for its money in terms of efficiency .... and is way more efficicent than the pumping losses of useing MIMA to force and EV-Mode from an Insight.

I am still strugling with where to poke the 3" hole for the blower hose for the forced cooling of the e-tek. The motor at 175A does not get that hot, but at the same time I am careful to only use it for short burst, and I do watch the temp. I balanced my 12V batteries so they are at the exact same SOC based on the open circuit voltage and sitting for several hours to stabilize. They are at 100% charge, and the solar input to the Vicor batmod dc/dc charger is in place but has not been tried(batteries are full)
I will tackle the blower today, and will then be ready for the first range test for the 5th wheel.
The Insight is still pretty light even with all the batteries. I was able to 5th wheel up a fair grade at 20-25 MPH the other day. It has problems starting up hill as one would expect, but that is mainly because of my 175A current limit. If I hit it with 300A, it would probably scrub the 5th wheel, and have much better take off, but a flat or slight down hill blast off is at a pretty respectable rate.
I wish I had another e-tek, as I have another scooter wheel.
I would like to leave the 5th wheel on the Insight, but build up another specifically for the generic 5th wheel trailor hitch trials.
Well as much fun as it is to sit in my cool basement and dream, I better get out there before it gets too hot to work and finalize that 5th wheel once and for all.

For those who may be interested in the "5th wheel" modified insight, check out

http://www.insightcentral.net/forum/viewtopic.php?t=5222

Or, just modify the existing rear wheels (of any hybrid) to incorporate electric traction motors that serve both as propulsion and braking when needed, coupled to lighweight plug-in Lion batt pack. Then you still have the ICE/IMA from the front wheels as needed. ??

Welcome to CleanMPG, iamian!

In the next few years, I hope Honda adds an EV mode so Toyota does not have the plugin hybrid market to themselves.

ralph
While that is of course possible, I chose the separate wheel and lead acid batteries for several reasons.

1. I wanted to use the smallest lightest most efficient motor possible, and to limit the max current to a level that the single series string of batteries could handle without having issues. The choice of batteries was purely cost based, no question LI Ion would be better, but the cost difference and complexity of battery control with Li Ion is 10- 20 times what the lead acid is.

2. Any additional un sprung weight on the rear wheels(motor) would present suspension problems, as the suspension is designed to damp and absorb shocks for a narrow range if wheel weights, An example: the present insight wheel/tire weigh maybe 13 lbs. Add a 22 lb e-tek motor, and we have 35 lbs, When you hit a pothole, the 35 lbs will drop into the hole, and then have to rapidly rebound when the edge of the hole is reached. The extra weight will need to be rapidly accelerated by the tire impact with the edge of the hole. The extra weight would likely generate an impulse force on the tire that could pop the tire. This is why we do not see many in wheel motors.

3. OK we don't mount the motor on the wheel, we mount it on the chassis, and use either a cv jointed axel or a timing belt drive. Both systems will be complex as the motion of the rear wheels needs to be compensated for, but a bigger issue is the constant load on the rear wheels. If the drive is to be for acceleration from a stop, and is geared to provide good torque in this 0 to 30 MPH, range, do we want to be turning the motor at 10,000 rpm when we are at highways speeds, with the resultant constant load on the drive train. The lack of a clutch to disengage the motor is the main problem here.

The mechanically simple 5th wheel keeps the motor weight on the sprung chassis, has an effective clutch in that it can be retracted over 30 MPH to totally eliminate any drag on the power train.

It also has the advantage of being removable, and does not need to modify the rear suspension except for the addition of the air helper springs to support the battery weight.
Can it be better of course, but it is an effective proof of concept that can provide some real world data on the practicality of such an approach.
Photos of my progress today:
http://99mpg.com/TheBestHybridmix/aircooled5thwheel/

In the next few years, I hope Honda adds an EV mode so Toyota does not have the plugin hybrid market to themselves.

I think in future Honda Hybrids they will continue with the Closed Valve Ev-Mode the HCH06 uses....

I am not sure where the two methods break even with each other.... when compairing the Prius mixing transmission vs the Civic closed valves Steal / EV-Modes....

Personally I know they didn't put the 2nd clutch in the Manual Insight becuase of delay issues ... but since a Manual Transmission is always more efficient then a Automatic Transsmission I would rather have the Manual over a CVT ... if only I had a clutch I could use the disengage the IMA motor from the ICE to run the way it is now ... or in EV-Mode without the pumping losses.... That would have better conversion efficiency then the stealth / EV-Mode Prius .... And could run at any speeds while still takign advantage of the gear ratios.

Wayne better watch out.
I went 23 miles at 0 gas consumption with an average speed of 27 MPH.
150 MPG, 0 L/kg you will have a rough time topping that.
I am measuring the charging with KW meter so I can see how much juice it takes to charge it.

I still had 45% SOC when I finished.
See the full report at:
http://99mpg.com/TheBestHybridmix/holybatdropingsrob/

What a neat feeling with the 3000 RPM Etek whining as I cruise at 28-33 MPH.
I really need to try a 3:1 ratio instead of the 4:1
This works pretty well.
:cool: :cool: :cool: :cool: ;)

FYI, There is a field in the database for the electricity you use if you plug in ;) Thats just to keep people honest (I don't even know if it works properly since there are no plugins yet in the database). I forget the formula I used, but remember to add it in if you top off the battery from an external source ;)

Hi Mike:

___Wait until we get to drive the EnergyCS or Hymotion PHEV-30’s. We will travel at up to 34 mph and consume 0 fuel over 30 + miles ;) Gen III hybrids and PHEV's – indefinitely ...

___What I would like you to do is look up the Mitsubishi’s MIEV concepts. They do have working prototypes on the ground in the states. These in-wheel motors were brilliantly designed in a very compact package. If one could be installed vs. 2 (I do not know if this would cause a severe yaw effect or not) for lower speed operation, you might consider something similar. I took a ton of close-ups of the MIEV concept at the 06 Chicago Auto show press event earlier this year but not a single one was any where near publication quality.

___While we are increasing un-sprung weight (detractors of the MIEV speak of this as its Achilles heel), for our driving envelope, it should work just fine. If Mitsubishi can come up with a Li-Ion pack of reasonable size for a reasonable cost, they are going to own the market in B-Class sized subs with maybe a 600 cc ICE as the long haul propulsion solution. A quick search through the news section should yield a few hits on the MIEV as well as Clett’s and my previous discussion of an Insight EV conversion around the net.

___Just two of the past news items photos. I would die to own that Colt EV based off the MIEV concept myself!

http://www.cleanmpg.com/photos/data/2/Mitsubishi_Colt_EV.jpg
Mitsubishi Colt - EV

http://www.cleanmpg.com/photos/data/501/Mitsu_i_car.jpg
Mitsubishi I car - EV

___Good Luck

___Wayne

I really think that with a different reduction ratio to the rear wheels, and a bit more amps, that this 5th wheel setup on my Insight could do 45 MPH and have a longer range than the prius with the expensive batteries. This is with 300 lbs of lead acid. Imagine the range if this was powered by 150 lbs of LI PO or LI Ion with 2-3 times the AH capacity. It really proves that you do not need much electric power to push an Insight.
A look at the terrain profile of my test run will show that it is predominantly up hill for most of the trip.;)

http://www.cleanmpg.com/photos/data/501/Mitsu_i_car.jpg


Does this car design look strangly familiar? ;)

Hi Mike:

___Today’s 34 mph limited HSD via EV button is a Toyota engineering constraint, not a hacker’s one just as Honda’s IMA was never designed as an EV (2000 Insight’s pre-ECU updates while empty and the HCH-II’s have very limited EV capabilities). Toyota/Ford need MG1 to spin the ICE up to 1,000 RPM and at the higher speeds, MG1 cannot create the RPM differential between the ICE and MG2 while spinning backwards to do that. We know it can in the real world but Toyota and Ford wanted a larger margin for whatever reason?

___The reason I mentioned the MIEV is because of its compactness. If Un-sprung weight were an issue because of the in-wheel/hub motors, imagine what a fifth wheel trailer would do to your driving dynamics while pushing or you towing?

___Finally, I would really like to see a pure EV converted Insight as you would be very close to the GM EV1 in terms of capabilities including further distance between charge due to the superior Li-Ion’s available today. An Azure drive with the Zebra Na-Chloride’s as seen in the Toyota Echo EVermont below or some A123 System, Valance, or JCI’s latest Li-Ion’s in a massively parallel bundle similar to the AC Propulsion - T-Zero w/ 6,800 18,650’s would suffice. If you want huge power, high performance, and lower cost, a larger number of off-the-shelf 18650’s might be a solution vs. the quotes you have received for a much larger Li-Ion pack/bundle from one of the major suppliers. Voltage matching, cel to cel balancing, cel temp and current limits, and control would be something you would have to work out but given your abilities, I can see this as another possible route you could take?

http://www.cleanmpg.com/photos/data/516/Echo_EV.JPG
EVermont - Toyota Echo - EV conversion.

___Good Luck

___Wayne

Wayne
All good feedback, but the $$$$ for better batteries is an issue I am not likely to find a way around.
Wheel motors are more elagant than an add on 5th wheel but are not yet readily available, and are also expensive.

I have a set of new tools on my car that I can play with and explore, I can start the prius battery based booster pack design, and with another UP your Volts, and the Altwheels festival in Boston, coming up soon, I have enough to do.;)

and a bit more amps, that this 5th wheel setup on my Insight could do 45 MPH and have a longer range than the prius with the expensive batteries. This is with 300 lbs of lead acid.

Have you guesstimated what Peukert's Effect is with more amps? I'm curious because I'd like to drop a similar system in my car.

I discussed my system with an engineer at trojan, the battery maker. The battery has a nominal AH at the 20H rate of I believe 110AH. The derating to 85AH is based on the Peukert Effect. I cannot tell you what my average current draw with the system was during the test run, but the peak was 177A, and if I was to guess, I would say 75A would have been the average. Trojan recomends a higher charge rate than my 3A, so the solar charging at ~6A should yield a faster, better and carbon free charge. It took more than 10-15hours to recharge.

Good point, thanks for correcting me.
I actually was estimating the weight of just the wheel, so you are correct about the total unsprung weight being much higher. The rear end components are steel, and could be even heavier than your estimate.
No matter, the extra 22 lbs plus the weight to mount and connect the motor to the wheel, would move things in the wrong direction. The spring is right where a rear axel would have to come off the wheel, so major reconstruction would be needed to tie into the rear wheels.

An interesting observation today as I was driving to the post office under 5th wheel power. The section of road was quite rough, but the wheel did not slip or bounce. The only time it seems to slip is when taking off from a stop when it is on a sandy point.
The unsprung weight of the scooter wheel is definitely down in the 8-12 lb range. (wish I hadn’t broken my shop bathroom scale) and I measured the down force at about 130 LBS.

I was looking at a cutaway view of the Insight IMA motor and clutch assembly the other day, and was thinking that if one could reverse the two parts, we would be able to turn off the engine, and drive with just the electric. When the clutch was engaged, things would work like now. To keep the spacing of the components the same, the transmission face plate would have to be milled down, and a spacer of equivalent thickness made to enclose the clutch assembly in the new position.
I will be able to get a close look at the disassembled assembly at the upcoming Up Your Volts.
http://www.auto-careers.org/up_your_voltage%201%20and%20one%20half.htm

the ability to use a clutch to disengage the ICE from the IMA while letting the IMA remain attached to drive the transmission... I think would be the ultimate option even if it would also be the ulitmate headache and pain to make happen... the IMA could push at any speed and still take advantage of the transmision effects... and it wouldn't have any pumping losses or extra friction....

There is a report I down loaded from the web where The University Of Michigan did a computer model of adding a 2nd clutch to the Insight to allow a Full EV mode.... :Banane04:

if you want to read it ... here you go:
www.geocities.com/ian_p_george/A-Practical-Hybrid.doc

anyway I really like the idea... I just don't know if there is space and such to let it happen.

best of luck with it Mike.

Wow it was interesting to read that. I have to contact those guys, and see if they can run a simulation on my car.
They felt that their simulation was not going to be practicle for the lack of having driven their creation.
They left the driver out of the decision tree. Driver skill would have solved their clutch delay, and their simulation already had MIMA, since they were going to controll the IMA with the motor off.
My Ewheel, has about 8.5KW peak output as set up, and I was maintaining 80 % of my 30 MPH flat speed up moderate grades. The Insights 14KW motor should be great for the flatlands, and even new england highways, at 50-60 MPH, just need to keep it fed with electricity, You would want all the AH you could fit, of the best battery technology.

I grabbed a calculator this afternoom, and ran some numbers on my 23 mile electric only drive.
It took 3 KWH to recharge it, I paid 17 cents per KWH on my last bill that means it cost me 51 cents. The best MPG I ever got on that section is 84. My 23 mile trip was 3.65 times shorter than the 84. 51 cents X 3.65 or $1.86/gal equivlant. Is that correct?
Granted I was only averaging about 27mph, which is much slower than the 84 MPG run.

I should have my solar charger operational tomorrow if the sun shines, so the Ewheel rides will be free.:) :cool: ;)

Hi Iamian:

___Thanks for that link as it is now in my own favorites! I have been wishing for a clutched IMA for true EV forever and if only Honda had followed through :(

___Mike, have you looked into the cost of the 18650’s recently? You could build a nice stack of Li-Ion’s for not to much and configure your voltages any way you wish. The 1,000 - 2,000 DD cycles of a Li-Ion alone let alone the Energy density are enough to scare me away from Pb-Acids in an EV no matter the cost savings up front :( The Tesla roadster buried the cel’s in a steel sleeve of some sort and surrounded the entire pack and its pathways by water IIRC. IIT is working with my company on Li-Ion’s immersed in a passive wax like substance in order to absorb the runaway of any one cel before it could ignite the adjacent. I would love to see a cost to benefit analysis of the Pb-Acid’s vs. a home built Li-Ion package you might consider cobbling together …

___Good Luck

___Wayne

Wayne
It is a nice article, I put it in my favorites box.
Why don't I look into the 18650’s, if I had a dollar for each time that was suggested.
If they were 50 cents each, I still would not consider them, Why:
The thing that bothers me the most about using a 1000 or more explosion prone batteries is the pure amount of work it will take to get to that first real ride with the batteries.
To design and build the actual package, with thermal and fire protection taken care of, if liquid cooled the choice of construction materials and coolant. We are talking many man months of work. The articles about the Tesla, the T-zero and the others that are building the multycell super packs, do not tell you how many recources were applied to the project, how many man years did it take to solve all the problems, how many people were working on it.
I am only one guy, I hate to even remove my 4 batteries it is an hour of hard work.
The testing alone that one must do to be confident that your pack will not go up in smoke, you with it, is many more man months.

I went to the battery store, gave them some money, and they gave me my 4- 85 AH AGM31 standard batteries, available in every area of the country, and from several manufacturers.
I can replace them for $800 if they get damaged.

I love a challenge as much as the next guy, but I have other projects that are suffering because of the time I have invested to date. OK I have started my experiment with the worlds worse battery, the heaviest, and the lowest capacity, orsimply the worse case battery. I accept that and will learn from it. I can only go up from here, and I am already able to go possibily 30- 40 miles pure low speed electric, or 50 minutes of 50-60 MPH Eboosted electric priority driving at 90-110 MPG.
Once we know how the worse case works, we can extrapolate. I could put 300 lbs of LI PO or LI Ion in the car as I will have proven that the air springs can handle the weight, the frame wont bend. The 300 lbs of LI would be over 400AH @48V 4.7 times what I have now. So I can extrapolate the Ewheel and Eboost ranges from that.

I like what I have for now. It is a perfect research tool, lets see what I learn as I put some time into driving it, I want to automate the systems and syncronize them under MIMA control. Then we see what happens. Winter is just around the corner, my rolling research lab is nearly finished to the point where I can start driving it in the enhanced modes, and see what kind of real world "worse case" numbers I can get. I have a broken,home made trifuel heating system that needs maintenance.
http://pages.cthome.net/genesisone/solar_page.htm

A "new" addition that is still unfinished after 3 years.
http://pages.cthome.net/genesisone/around_the_house.htm
(My dear patient Wife).
So I will be tinkering with the prius BCM project, fixing my heating system, and my addition, and having a blast playing with my MIMA modified,Eboosted battery, and Ewheel equipped buggy
:) :cool: ;)

Yeagh ... when I found it I liked it so much I just down loaded the whole thing to keep. :)

I still hold out hope for the clutch IMA EV-Mode for the Insight./.. but Dont' be fooled it is a MAJOR Project...

As for 18650... I also have mentioned this before as well myself...

it turns out 2Amps is "Safe" for a 18650 for current so you would need at least 8 in parrallel 10 would be better to get to the ~16Amps of boost Mike is doing now... and to get up to voltage you would need 40 or more in in series... so you are already up to at least 400 or so cells to get a booster pack going that can compete energy wise with what Mike has in Lead Acid just for a booster battery.... 400 Cells in a combination of series and parrallel is just asking for problems... the only way to do it is the multi-level steps that the T-Zero and Tesla use ... and IC on each and EVER single cell to cut power to and from it if any of the following conditions happen .... Over Current Chargeing or discharging... Over Voltage ... and under voltage .... Acording to a nice chat I had a while back with the makers of the T-Zero they get thier 18650 cells with such an IC already attached.... the only place... I know of to get such a product is : http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2557

and in 101 or more orders you get the discount of $12.76 per cell + Shipping

so a minimum of 400 x 12.76 = $5,104 + Shipping.... But wait that's not all.... you will also like the T-Zero and Tesla ... need a battery balancing system to balance the Voltages / SOC of the multi level packs.... From what I understand T-Zero and Tesla use a Battery Ballancing System for each series string.... and then another one to balance the parrallel strings.... So you still need a BMS for the cell and pack balancing and you have already spent over $5,000 .... so way more expensive than the $800 of the lead....

But to be fair to 18650 .... at ~50Grams per cell x 400 cells = ~20 Kg x 2.2 = ~44 Lbs + Battery Box / Packaging.....

So thetre is no doubt that the 50~60Lbs or so of 18650 will be lighter to dish out the same power as the lead's 300Lbs .... but $5,000+ vs $800 ... is a big difference .... plus you also still have the man hours of work to design ... test.... and fabricate all of that 400 cell system and as Mike said that is a major project in itself.

I like the 18650 Idea ... but ... it is a major effort to say the least...

Most EVs that are willing to spend the money to go to Li ... just go for the bigger cells ...

As for Bigger Cells .... not many places cell them ... www.powerstream.com does.... but you still need ~40 or so in series and a BMS for them and 12Ah Cells that can take ~30Amp discharges are ~$75 per cell x 40 = at least $3,000 + Shipping just for the cells ... then you still need a BMS ... so you are still back up to the $4,000 to $5,000 range.... and all the work to design ... test ... fabricate....

at ~470g per cell x 40 cells = ~19kg x 2.2 = ~42 Lbs.... so about the same weight and cost as making that monster 18650 pack.... but only 40 cells instead of 400.... so allot easier......

but to be fair again to the 18650's ..... 3.6V x 2Ah = ~7.2Wh x 400 = ~2.8kWh

3.6V x 12Ah = ~43.2Wh x 40 = ~1.7kWh

so the 18650 will end up giving more power storage for the same cost and weight range as the larger Li cell... but will be 400 cells vs 40 cells to deal with.


I for one would rarher deal with the 40 cells...

I forgot.... 10Ah NiMH D Cells are another option that always comes up....

These Might work for a Booster:
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=325

they can do the 30Amp discharge rates... and store 10Ah .... you woul need at least 120 of them in series to get up to voltage and of course any battery pack with 120 cells really needs a BMS system....

when you buy 101 or more again you get a discount but at $5.56 per cell x 120 cells = $667.20 + Shipping..... way cheaper than Li of any kind.... now you would just need a BMS for them... but that is easily going to be as much or more expensive than the Batteries... and at ~160g per cell x 120 cells = ~19kg x 2.2 = ~42Lbs again... so about the same weight as the Li but much cheeper.... also less power .... 1.2V x 10Ah = 12Wh per cell x 120 cells = ~1.4kWh

I am more of a fan of the NiMH Path as it is a big weight savings over Lead ... more expensive than lead after you add in the neccessary BMS ... but way less than Li of any type...

Ian
Just to add a bit of info. I feel that the 16.5 A boost charge is not enough, and that 20-25A would be just right. I have to be very careful not to deplete the battery even with the boost on. Of course I am trying to keep the ICE in lean burn the whole time,at way over 100MPG so the ICE is not contributing a lot of power. I am trying to find the best PIMA setpoint for assist to allow continous electric priority.
On the booster system current draw, I am using 60-65A all the while the boost system is on. I use about the same average power to run my Ewheel, where I am using no gas. I have to get to Worcester and drive some of the streets that have stop signs at every block, with and without the Ewheel blast off to see how much improvement I can get there.
The fun is just begining.
If anyone wants to build up a booster pack of other chemistry batteries, I will be happy to try and lend a hand. Lets get a few more of these Eboosted Insights with Ewheels on the road.:) :cool: ;)

What about SAFT NiCDs (http://www2.ald.net/~roden/ev/pages/saft.htm)? Expensive, but they'll last a long time.

Maybe someday Mike.... Some day , somewhere, some people , did some stuff...

anyway.... any Booster Battery would need some kind of Voltage and current control going to the Honda stock Pack.... and most system it would be best to have some type of BMS ... so the DC-DC moduel type of thing you have going , or something silumar to it is a must as a starter... to that you can connect almost any type of battery system ... but the battery system will be safetest and work best with a BMS of some kind.

The Memory effect with NICD could be an issue, but if the pack is cycled fully each time I would imagine that it would not be a big factor.

Iirc the saft site says a similar battery has something like 150,000cycles@5%dod, and 2,000cycles@80%dod, so minimal discharges might not be that bad. It seems the biggest drawback is charging since it requires a specific algorithm.

One of the big advantages to my modular dc/dc converter scheme is that batteries can power all 11 converters input in parallel from one big battery pack~65A, or individually with 11 separate 5.5A 48V packs, or any combination of parallel input configurations. The input voltage requirements of 36-72V is also quite flexible. NICD, NIMH, LI, and lead acid will all work.

Are the DC-DC modules more efficient the closer the input voltage is to the output voltage or is thier efficiency more directly tied to current flow rate?

On a side thought.... do diodes heat up .... well.. everything heats up with enough amps... but I mean the voltage drop on a diode I always thought was not caused by a internal resistance as other voltage drops .. becuase the diode voltage drop stays about the same even as current increases... and if it were a internal resistance then we shoul expect the voltage drop to increase as current increase V = IR .... I am wondering what the actual resistance / losses are of current going threw a diode might be.... I guess if you monitored the temperature change of the diode at a known current you could use the P = R*I^2 ... to figure out the resistance .... Just wondering about that voltage drop.... is it due to some funky resistance that gets smaller with larger currents or is it something completely different?

What kind of efficiency loss is it to convert the DC to AC .... as AC you can convert it up and down in voltage with nearly no losses... and then rectify it back down to DC from the AC when it is where you want it to be.....

Just some crazy ideas.... thanks for any input...

Ian.!

Ian
The quasi resonant system they use in the Vicor converters is good at taking a wide input voltage range, and converting to a fixed voltage output, with an almost flat efficiency curve.

Yes diodes do convert a lot of the band gap voltage drop into heat, thus the big heatsinks on my boost converter diodes.
The band gap voltage gets higher when the diode heats up, which makes the diode dissapate more heat.
Thermal runaway is when the extra heat generated makes the voltage higher so more watts are generated so more heat is generated till the part melts down, usually as a short or open.
The MIMA temp sensors are actually based on the voltage change in the diode band gap with temperature as it is a very predictable and repeatable signal.

The diodes were necessary to prevent a failed converter from bringing down series output, and the 16.5 amps has to pass through all of them, lots of waste, again worse case. There are a lot of good lessons to be learned from worse case.
I have basically settled into wanting a single dc/dc converter like the Absopulse unit that we first looked at. The single converter was much more efficient if I remember correctly.
I need the 48 volts for my Ewheel, so I will always have a 48V boost supply.
I have the Low Voltage Ewheel setup.
The guys that are on the highway for most of their commute, have the High Voltage booster pack.
There is no reason that a 180V boost supply with say 20 AH, would not do a nice job of boosting the main pack, we need to design the current controller, which will in a way be a simple dc/dc converter. That could be the simplest from the hardware standpoint.

Have you downloaded the schematic, and looked at the Vicor data sheets? you may find it interesting.
I will add a theory of operation note on the schematic so that you can fully understand the circuit. You better hurry up and get your EE degree, so you can get to work on this.;)

if you mean the boost charge control schematic... then yes I have looked at it.... but I admit I do not understand all of it.... but that is just becuase of my limited understanding.... and yes I did look at the victor site and the DC-DC module information there for a few different modules they have....

I agree that a single higher power ~3,000Watt or so DC-DC controller would most likely be better .... should be easier to increase efficicency ... and fewer components always means less to go wrong / less complex .... you know .... couldn't we use a DC Motor Controller to controll the voltage and current output to the stock Batteries from the booster batteries ??? since voltage and current control of a DC motor is what the DC motor Controllers do????

I guess from a high voltage booster battery via prius cells or whatever the main thing we need to control is the current since we can size the high voltage bootser battery to 180~190V wihtout too much problem ....

Yes it is very likely that a 190V motor controller could do the boost current control job. That is an idea worth looking further into.
Get one with regenerative braking, and we may even be able to recharge the boost battery from the regen?
Good idea.

50 mile Ewheel checkout
I started hearing a strange sound from the Ewheel yesterday, so I will pull the assembly again to check it out. A quick look, tells me that the setscrew that holds the motor pulley to the keyed shaft has loostened up again. I increased the size of the setscrew from 10-32 to 1/4-20, the last time I had it apart for the same problem. The key is not as tight a fit as it could be, and it allows a small rotational motion which under the heavy load of pushing the car, seems to loosten the setscrew. I will start by making a new key that is a tight fit to hopefully eliminate this issue.I have about 50 miles of use on the assembly, as well as driving through a very heavy rain storm, so it is going to be interesting to see how my sealing job has held up.Will advise.

I wonder if having something like a really low Rds MOSFET across
each converter module, to simply bypass it if if fails, would
improve matters? Then you could have one diode at the + end
to protect things, but less voltage drop along the chain. You'd
have to make sure the module wasn't producing anything anymore
before gating the MOSFET on, or make it beefy enough that it
could handle a brief short and force the module to shut down..
.
_H*

Hobbit
The diode configuration I used on the boost supply was the way Vicor recomend for series output connections of their modules. I looked at Shotkey diodes which have a lower drop, but at 16.5A, they were only a bit better than the standard ones I used. Lots of room for improvement. I would like to configure a similar system with their 500W modules so I could get boost in the 20-40A range if necessary, I can always lower the current on a higher current module, but I can't raise it on the units I have now.
A low RDS mosfet would offer some advantages in voltage losses, but not in circuit simplicity.

What if we could take our non hybrid car, install a trailer hitch, plug an electrically driven 5th wheel into it, throw some batteries in the trunk, mount a hand throttle in a convenient spot near the drivers seat, and have a mild hybrid that can drive from 0-30 MPH with plug in recharging. Regenerative braking would be a plus to extend range. 0-45 MPH should be possible, on a light car like the Insight.
The Prius with the stealth mode, and ev switch have that feature, but with the heavy car, and big motors, range is again a matter of battery capacity.
The insight is so light and slippery that even with the boost batteries and 5th wheel it remains easy to push, and without sacrificing the range advantages of the Hybrid, I have an EV up to 30 MPH.
It is soooo much fun to cruise down the main street with the electric whine sounding like a landing flying saucer.
The removal of the muffler to make room for the wheel actually makes the car sound cooler.The deep put put sound reminds me of some European sports cars that I have driven in the past.
The loudness is directly proportional to engine load, and can replace the MPG display as a MPG feedback.
I wish the e-tek motors were easier to find, as it seems to be a nice performer for the 22 lbs of weight it adds. The mechanical system is fairly simple now that things have been fitted once and we know that it works, we could have a 5th wheel kit so more Insight owners could play with the concept.
The any car 5th EV wheel would take some more prototype work as the motor/wheel system would have to follow the car like a trailer, so it would need a special attachment device. To make this mount universal so it would fit many vehicle styles would take some tinkering as well.
What a difference that could make, people exposed to heavy stop and go traffic could get infinite MPG while driving in the city. That alone could raise the average MPG of the American fleet substantially.
The size of the system would not be restrained like it is on the Insight, so one could have a big unit for vans and pickup trucks, and add battery capacity if the commute is long. When the van is dead, move your e-booster 5thwheel to your new Van, and off you go.
Very interesting set of possibilities.
:) ;)

Hmmm.... And what is to provide the traction ( on the 5th wheel) required to 'push" the vehicle ? Seems to me to be a whole lot of tire smoking going on! Did you ever try to push a stationary vehicle to some (?) speed? Eat your Wheaties!!! Weight! Weight! Soon, no more advantage! You never get something for nothing! IMHO....

Hmmm.... And what is to provide the traction ( on the 5th wheel) required to 'push" the vehicle ? Seems to me to be a whole lot of tire smoking going on! Did you ever try to push a stationary vehicle to some (?) speed? Eat your Wheaties!!! Weight! Weight! Soon, no more advantage! You never get something for nothing! IMHO....

The 5th wheel is pressed down against the road... I forget the exact amount of pressure mike uses... downward force like this from whatever source is all that keeps any tire from spinning on a car... it is a competition between the static frictional forces of the tire which is a result of tire downward pressure and the static coeficient of frition for the tire... and the torque on the tire... if the static frictional force is greater you move forward if the torque is greater the wheel spins.... It gets more complex in the real world becuase tires change in shape and the materials frictional coeficient changes with temperature and road surface.... Mike has reported a few instances where he did spin a bit... but over all it doesn't spin that much... but if he increased up to the 300A the motor can take then allot more downforce would be needed to keep from spining the tire....

As for pushing the car around... some cars... 4,000+ lbs cars maybe.... but if you have ever tried to push a Honda Insight around it is a completely different animal... I can personally 1 person push the insight around easily even up small hills.... try to push a less than 2,000 pound insight around some time... you will see the lower weight is a big thing.... if I ridged something up I could probably easily pull my insight with my bycicle up to about 15 to 20 MPH....

And it is well known that the 5th wheel is not getting something for nothing... it is getting several miles of transportation useing the alternative fuel of electricity stored in the batteries instead of the gas... Electricity is better for the environment then any other option for the car is... and to boot it is far cheeper per mile.... so the cost is the initial cost of the 5th wheel work.... and the on going cost of operation that is less than gas... especially now that mike is chargeing with solar cells.... are solar cells free... no but they will put out more energy in thier useful life time then it took to make them.

As for how far you have to go before it looses its useful advantage??? well if he gets 30 miles then it has to be way more than 30 miles as the extra weight carried around will not pull down the MPG numbers that much... Even if he drops to the 50's or MPG after the 30 to 40 Miles.... it is the same idea as pulse and gluide.... you glide ( use the boost and 5th wheel ) and then pulse ( use the gas engine ) .... Realy world numbers for the break even point when it is better to not have the extra weight ... I would suspect you would have to go over 100 miles per battery charge of lead acid to reach that point.... and likely over 400 miles per battery charge with Li .. baterries....

but mike knows the system better than I do.

I have about 130 lbs of down force, which is provided by the 70PSI in the spare tire acting through a 2.5" bore air cylinder.
The only time it seems to have a scrub out issue, is when I am trying to take off on sand, or if the road has a dip that allows the air cylinder to reach the end of it's stroke. The present system has enough power to accelerate on the flat to 30MPH at a reasonable rate, and can climb small hills with only a 3-5 MPH loss of speed. If the car was 3000 lbs, more down force, and more power would probably be needed.
It is really great in stop and go low speed traffic, and on deserted secondary roads where the 30 MPH top speed will not obstruct traffic.
The MPG hit for just carring around the dead weight is not really very noticeable, I can get 60-80 MPG if I drive carerfully just like before. Turn the dead weight into power supply,with the Eboost and Ewheel turned on and we get 100+ MPG. It works quite well.:cool: :) ;)

Upps!
I was at a stop yesterday, that without me being aware of it, put my Ewheel right on a patch of sand and small stones. When I took off, the Ewheel spun out, and shot the stones out the back like a slingshot. Good thing there was no one behind me.
I will have to watch for that in the future.:eek:

Driving back from Sleepyhollow NY, I got stuck in some construction delays on I 95. I dropped my Ewheel, and used no gas for the 10 miles of bumper to bumper stop and go. What a great feeling to know that I produced no CO2 while all around me hundreds of lbs of it were being spewed from everyone else. You should have seen the people in the other cars as the Batmobile cruised by sounding like a flying saucer.:rolleyes: ;) :cool: Great Fun

Honda should start building the Insight again with your 5th wheel as standard equipment! :mad:

Hi Mike:

___Your thoughts on a serial hybrid/EV with a small ICE in the Insight to make the thing run like it should … Given the most HP I may have every used in my Insight including Assist was maybe 50 HP but the average was more around 15 – 20 HP. Honda makes some darn fine single cylinder ICE’s for mowers and such. Some of the best in the world in fact although their emissions would be horrendous until FI and the multi-layered emissions systems were installed … What if Honda were to install a 25 HP ICE and run it into a serial based pack with large enough capability to pop out 80 HP for a 2 minute or less burst? I could easily see the Insight in the 150 - 200 mpg range without even breathing hard. I believe the Prius III might be heading in this direction with a lot more peak power from a larger Li-Ion pack and a smaller ICE for better highway cruise FE in the not to distant future (WAG here)?

___Good Luck

___Wayne

It sure is a blast to use.
At the training session we did some maintenance on my car, and found a stuck brake pad on the driver side front wheel. The rotor was dragging pretty bad. I thought the slugish performance I had been feeling was the battery weight. We freed it up, and got the wheel to turn freely. What a difference. It must have been stuck for some time, as the rotor was blue from being heated. Will never know if Madison and Ipswich MPG runs were effected ?
I will do the brakes, and do some more test runs on my favorite MPG route.

Wayne
I wish there was a way we could convince Honda to make the whole running chassis and body of the Insight, available for research, and leave out the electronics and the engine. The car is a perfect test vehicle for experimenting with just the type of system you have outlined, As well a pure EV.
I guess in the real world we will have to grab all the used ones we can and start from there.

Maybe we need to start stock piling Insights so we can try out some of these ideas.
I have a big back yard, good place to start the pile.;) :)

Mike, be careful what you wish for as I have a bunch of old Saabs that I'm now having trouble clearing out. The Sonett (http://www.katiekat.net/Vehicles/PhotoLinkSonett.html) has a Cd almost as low as the Insight and weighs hundreds of pounds less. I can still get an adapter plate for the transmission to mount an electric motor, but inhub drive will hopefully also continue to be developed - see the ridiculously overpowered MiniCooper (http://www.treehugger.com/files/2006/08/the_hybrid_mini.php) ... but all this will have to wait as we're going off cruising again for a while.:Banane30: Hopefully lightweight lowcost batteries will be available when I return. All the best to you.

Joes
Have a nice cruise, I hope the batteries will be available buy then as well, but I expect that you will be back before the price starts to drop.;)

Hi Mike: Upps!
I was at a stop yesterday, that without me being aware of it, put my Ewheel right on a patch of sand and small stones. When I took off, the Ewheel spun out, and shot the stones out the back like a slingshot. Good thing there was no one behind me.
I will have to watch for that in the future.:eek:
___I missed that one … That could come in handy in more ways then one ;)

___Good Luck

___Wayne

Wayne
So you would have stoned me with the Ewheel at the Tour de sol when I was following to watch your technique.:eek: shame on you;)
I have been playing with a Prius synergy drive, with the idea of making a hands on demo of how it works for the next UYV.
I could not help thinking about what the 40HP Prius motor with its built in cooling system would do if mated to an insight that had all the ICE/IMA stuff pulled out. I would leave the 5 speed tranny, and probably leave the clutch for safety???
:cool: ;)

I picked up a piece of truck tire that pulled the 175A Anderson connector against the road, and made a mess of the wire.
While repairing the connector,I did a lube and inspection of my E-Wheel.

The motor brushes are only down by about 1/4 in.
The blower bearings were toast, so I will have to find a better way to cool it.
I have a few photos at:
http://www.99mpg.com/Projectcars/TheBestHybridmix/

While the E-Wheel allows city driving at up to 30 MPH, it is no use above that as the 4:1 final drive maxes out in motor rpm.

I want to convert it to a 60MPH 2:1 ratio, but worry that the scooter tire will not hold up to that type of abuse. I find my self usually accelerating with the gas anyways, so why not gear it so I can see how things work at that speed range. Maybe a 3:1? will have to see what ratios are available.

Can anyone suggest a tire/wheel of about 12.5-13" diameter that is rated for 60 MPH?
I was thinking a small trailer tire?