PML’s In-Wheel Motor, Plug-in Series Hybrid MINI
25 August 2006
|The MINI QED.|
PML Flightlink and its partner Synergy Innovations recently unveiled an in-wheel, plug-in series hybrid conversion of a MINI at the British Motor Show, the MINI QED. The car, one of two the partners have so far produced, serves as a testbed and demonstrator for technologies the company—which designs and manufactures electric motors, joysticks and drive systems—hopes to commercialize.
The QED currently uses four 750 Nm brushless permanent motors in its wheels, a 21 kWh lithium-polymer battery pack and a 250cc two-cylinder, four-stroke engine as the genset. The QED supports an all-electric range of 200-250 miles and has a total range of about 932 miles (1,500 km). The car accelerates from 0-62 mph in less than 5 seconds.
The QED uses a 350V, 11 Farad ultracapacitor to discharge the high current for acceleration and to accept the regen power back from braking. This protects the batteries from high current spikes.
PML is working on the engine component and may change it in the near future. Emission testing is part of that process.
The driver can specify an all-electric Eco mode in which the engine will not start unless directed by the operator. In the normal operating mode, the engine starts when the battery drops to a 50% state of charge (SOC). A third mode—sport—offers an enhanced performance profile on top of the normal mode.
Anti-skid and traction control capabilities are built into each wheel. The anti-skid function dynamically monitors each wheel to detect the onset of skid onset, and then manages the system to obtain maximum non-skid torque from the wheel in either acceleration or braking modes. Traction control dynamically distributes torque when any wheel is in skid management mode.
An option provides steering wheel feed-forward input to the traction control system, allowing driver in tent and wheel alignment to influence stability and traction. Another option would provide further stability input through attitude, yaw and gyroscopic sensors.
PML FlightLink has also developed a prototype electric scooter—the PRAZE project—with European partners including Peugeot and with support from the European Commission.
Very nice! I'd hate to see the price tag though.
The beauty of in-wheel motors: Ultimate control of the driving wheels...traction control, ABS, stability, yaw, every dynamic can be programmed in and with a sufficiently powerful DSP employing a well thought out PID algorithm you can do all the sensing on the motor itself without external wheel speed sensors and the like.
Now if only I could buy a conversion kit to give myself AWD with rear-wheel in wheel motors and small battery pack (1-2kwh). My car is almost 400lbs lighter than the average mini.
Posted by: Patrick | 25 August 2006 at 09:14 AM
I wonder if this would work in retrofits to make all cars hybrids? Does anyone know?
Posted by: Richard | 25 August 2006 at 09:24 AM
This is getting close to what I have been trying to give away for several years.
Note: With 3000 NM of thrust, not another car in the world can equal it. Just be careful what you do leaving stopplights.
It could flip over backwards!
Posted by: Lucas | 25 August 2006 at 09:56 AM
From PML's website:
Learn all about our new 4-wheel drive electric hybrid Super Mini (Min.e) as seen at this years International Motor Show London.
0-60mph in 4.5 seconds!
Top speed 150mph!!
Using PML 'In wheel' motors, drives and power control electronics. New driver touch screen interface, 3 driving modes; Eco, Normal, Sport, Power boost function in Sport mode.
A big step towards the future of Hybrid technology!
Posted by: Lucas | 25 August 2006 at 10:01 AM
Richard, this (as a retrofit) would be best suited to make a car electric as a standard vehicle with the electrical components would be overpowered (make for a good drag racing vehicle though I'm sure!). A two motor version may work well if you bought a car with the low-end engine. (e.g. A 4-cyl mid-size sedan may be a reasonable retrofit candidate but if you opted for the V-6 it doesn't make as much sense unless you are building a drag car...too much power, less fuel economy gain due to weight).
Then again if your intention is to completely replace the entire drivetrain of your current vehicle with the entire drivetrain proposed here that is a different matter altogether. Even if you do the labor yourself the components (batteries) are likely to be nearly as costly as a new car. I'd do it if I could despite the cost.
Posted by: Patrick | 25 August 2006 at 10:07 AM
Wow!! Sounds too good to be real. No mention of price.
Posted by: Dursun | 25 August 2006 at 10:28 AM
About the torque:
Remember most vehicles have gearing (for example my car is roughly 13:1 in first gear due to a ~3.5 1st and 3.72 final) to multiply torque...of course that torque is not available at close to 0rpms as an electric vehicle but this has no gearing due to it using in wheel motors. Then again with so much torque available from 0rpm you don't need nearly as much multiplication to move a vehicle (in the case of my vehicle peak torque is at 4500rpm with 85% torque only available once ~2500rpm is reached requiring significant multiplication to get it moving from idle at a dead stop).
Posted by: Patrick | 25 August 2006 at 10:54 AM
With an electric range over 200 miles, and a 21 kwhr battery it's using less than 100 watt-hours per mile. Sound almost too good to be true....
Posted by: Nick | 25 August 2006 at 11:41 AM
This is what I'm talking about! I can hardly wait to see this product take off. Ideas like this have been around for years, but now tech is making it more viable. I hope something like this will make it mainstream. Lucas, if your name is all over this, how come nobody's heard of it yet? Other people have had these ideas for years, too. Hard to say who's first.
They're mixing ultra-caps in with the battery system: Excellent! All I see on their website is talk of DC motors. No AC I guess. Too bad, cause I would love to see this thing perform with Raser's induction technology added.
They use a 250cc four stroke twin as the genset engine. Wonder if it is something like the engine in the Kawasaki ninja 250: that bike can get 70 miles to the gallon with some people driving. Hayes Diversified Technologies are the guys building/converting the U.S. Military's new diesel motorcycles! They are Kawi KLR650's with a purpose designed 611cc normally aspirated, single cylinder diesel engine. That bike (the still to be released civilian version) gets 102 miles/gallon at rougly 55 miles per hour, so they say. (I believe it.) That would be a much better engine even: more torque/power and better mileage with built in fuel-flexibility. The steady revs needed with the generator would make it even better. Then of course there are the Rand Cam type engines coming out soon...this has a bright future indeed. *If* they can get the price to a semi-reasonable state...
Posted by: John W. | 25 August 2006 at 11:41 AM
In-wheel is some cool stuff, however, will suffer from a durability standpoint. The wheel compartment overwhelmingly takes the most abuse from water, dirt, debri and the continual bouncing. The jolt of a couple of good potholes at 30mph is enough to scramble the brains of most electrical components. ABS has been in cars for 2 decades and most systems have 'glitches' from time to time. 'Glitches' is not a word I want associated with my drive train.
Posted by: Joseph | 25 August 2006 at 12:05 PM
Good news. By combining most of the newest technologies into the same vehicle, the results seems to be outstandings.
Why couln't the major car manufacturers do the same or more? I fail to understand why people like GM, Ford etc with huge R & D resources don't come up with better ideas. Puting huge diesel engines into 4-ton pick-up trucks is not very inovative. Why are all their engineers doing....
Where is Mitsubishi with their own in-wheel electric car?
Posted by: Harvey D. | 25 August 2006 at 12:13 PM
I don't want money or fame. I just want somebody with the means to build these things to build them.
I'm an old man. I sure would like to see something I thought of thirty years ago come to fruitation before I'm gone.
Posted by: Lucas | 25 August 2006 at 12:22 PM
This Mini is amazing! The designers did pretty much what I was hoping they'd do to electrify my favorite vehicle right down to the ultracaps. I would trade in my current Mini immediately if they became available.
Posted by: Mark Martino | 25 August 2006 at 12:33 PM
We've had fantastic prototypes for years. What are the chances that a car company is actually going to put one into production? I am extremely pessimistic.
Posted by: marcus | 25 August 2006 at 12:58 PM
Joseph- Not sure about the mini concept car but their website indicates the in-wheel motors are IP65 rated. Basically impervious to dirt, dust & mud penetration and will resist pressurized water jets from any angle. If they go for IP66 rating then it will even be submersible for 30 minutes in 1 meter of water. They could probably Mil-spec (mil std810) it for vibration endurance...but I too wonder about the long term viability. Perhaps they require a minimum tire sidewall dimension when their motors are in use.
Posted by: Patrick | 25 August 2006 at 01:00 PM
Lucas, If you have some great innovative idea and nothing better to do with your time (you make it sound as if you are old enough to be retired) rather than sitting around wishing for someone to develop your idea why don't you just go to www.grants.gov and find a grant that your idea will fit into. If you have the technical knowledge and capabilities requried to develop your idea it should not take too much to write the Proposal, obtain the grant money, develop the idea and publish it. If you put it out there before anyone can submit a patent application then you can make it freely available to anyone without anyone ever being able to buy the patent and restrict the use of your "technology". This way all you invest is your time.
Posted by: Patrick | 25 August 2006 at 01:40 PM
Thanks for the thought Patrick.
I've got a full and happy life without messing with the "government".
You might be amazed at the things I've "invented" years before they came on the scene. A few experiances of trying to explain a totally new concept to a pack of "engineers" will cause you to run the other way.
They have no problem explaining why it won't work. They never seem to be surprised when it does.
Posted by: Lucas | 25 August 2006 at 01:52 PM
Lucas: have you ever tried inventing a sense of humility?
Posted by: Tim H. | 25 August 2006 at 03:34 PM
100 watt hours per mile...Is that correct?
Posted by: cs1992 | 25 August 2006 at 04:08 PM
If you don't toot your own horn, who will?
Posted by: Lucas | 25 August 2006 at 04:21 PM
Is this still a 4 seater or is it down to 2 seats ?
How much space does all this take up ?
Is there any space left in the boot (trunk) ?
If there is room for 4 and luggage, they may have something, else they need a bigger car for the bag of tricks - say a BMW 3 series.
It might go well with the 320D which we are lucky enough to have in europe.
Posted by: mahonj | 25 August 2006 at 05:12 PM
"21 kWh lithium-polymer battery pack ... an all-electric range of 200-250 miles."
That is 76MJ/320Km or 24MJ/100Km. Which is half the best figures (which were lab figures) out of the DoE electric car project.
2002-01-1916, Electric and Hybrid Vehicle Testing by James E. Francfort and Lee A. Slezak. [PDF]
The actual use figures out of that project were about twice the lab numbers.
Furthermore a 21KWh (76MJ) battery is going to be pretty heavy. Currently available Li-ion batteries run .72MJ/kg tops. So that is 100Kg in batteries alone.
Finally, I am not an automotive engineer, but I have always understood that unsprung weight, like in-wheel motors, was detrimental to good handling. I think the in wheel motor approach is used in some heavy equipment, but that is usually off-road.
Posted by: Robert Schwartz | 25 August 2006 at 09:35 PM
Hi Robert, 100 kg's for the battery alone is not all that bad. Consider the weight of a normal gas engine with the transmission together, both of which will be missing on this vehicle (not counting the genset, of course). It's very doable. I'd live with it for a genset powered EV!
Posted by: John W. | 25 August 2006 at 09:56 PM
Mini 1.6L DOHC engine and tranny (manual) is likely to weigh around 400lbs together and add another 140lbs for the stock gas tank (full).
Unsprung weight on the wheels is detrimental to handling but then again the fine control over the individual wheel speeds will make up for that.
Posted by: Patrick | 26 August 2006 at 08:54 AM
I am working on a project in Pakistan to develop an electric auto-rickshaw (3-wheel taxi) and we have been doing a lot of mixing and matching to get a product on the road which is not so much a technological marvel but something actually commercially viable.
I must say that the 0,1KWh per mile claim may only be true downhill and 21KWh battery pack seems more 250Kgs terriory.
Posted by: Hasan | 26 August 2006 at 09:27 AM