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Canada Power Transportation News

Canadian Researchers Create Wireless Charger For Electric Cars 179

Posted by samzenpus
from the power-up dept.
An anonymous reader writes "University of British Columbia researchers have developed a wireless charging system for electric cars. It involves a spinning magnet beneath the parked vehicle which turns another magnet in the underside of the car. Charging takes four hours and is about 90% as efficient as plugging in. From the article: '"One of the major challenges of electric vehicles is the need to connect cords and sockets in often cramped conditions and in bad weather," says David Woodson, managing director of UBC Building Operations. "Since we began testing the system, the feedback from drivers has been overwhelmingly positive." Four wireless charging stations have been installed at UBC's building operations parking lot. Tests show the system is more than 90 per cent efficient compared to a cable charge. A full charge takes four hours and enables the vehicle to run throughout an eight-hour shift.'"
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Canadian Researchers Create Wireless Charger For Electric Cars

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  • by AliasMarlowe (1042386) on Sunday October 28, 2012 @10:36AM (#41796657) Journal
    OK, so it can double as a garage heater in winter. However, in the snowier parts of the country (i.e. NOT Vancouver and its suburbs), this will not be appreciated for outdoor use - lots of meltwater turning into smooth ice...
    • by Anonymous Coward on Sunday October 28, 2012 @10:56AM (#41796845)

      Let's see if you're right. A Tesla Roadster has a 50kWh battery. Charging that in 4 hours requires 12500W of power. 10% of that is lost compared to the cable charger. That's 1.25kW of heat in addition to the heat from the inefficiencies of the rest of the charging system and the battery. That's in heater territory, but not enough to significantly heat an uninsulated garage. Problems with molten ice and snow can't be much different from parking a car with a warm engine.

      • IRRC the biggest unknown with these chargers is that it's effects on a small animal that chooses to sit right in the path of the inductance loop is largely unknown.

        It's a bigger issue than you would think, since it does put out some heat, it is extremely likely that your family cat will find a new favorite sleeping place under the car.

        Granted the biggest risk might be that of a 'squashing' incident when you park or drive off without first checking for your loved one; but the effects on living tissue of spen
        • Re: (Score:3, Interesting)

          by Prune (557140)
          Unbelievably ignorant comment. The 12.5 kW is running through the free space between the cat's electrons and nuclei with only a tiny tiny fraction of it impacts anything in the cat, none of it having any physiological effect. It's been long established that magnetic fields are basically inert to biological matter. In 1997 they levitated a frog using 16 Tesla field, which is orders of magnitude stronger than anything used here, and the frog had no subsequent physiological problems: http://www.newscientist.co [newscientist.com]
          • by xQx (5744)
            You and your *science*.
            Consider me re-educated.

            Here's two news articles saying that the systems shut down if they detect an animal (or a fork) in the way:

            http://www.techradar.com/au/news/car-tech/wireless-electric-vehicle-charging-explained-1094646

            http://www.treehugger.com/cars/wireless-car-charging-action.html

            So I'm not sure if they don't believe your science; or if they are just placating the ignorant masses. (Probably the latter)
            • by putaro (235078) on Monday October 29, 2012 @05:28AM (#41802437) Journal

              Different type of charging system.

              The charging system in your references is working via induction - basically a transformer and the energy is transferred through an alternating magnetic field that creates a current in the coil on the car.

              The system that's references here appears to use a magnet to spin a magnet on the other side that then spins a generator. I'm not sure exactly how the intensity of the magnetic field would be different because the power is still being transmitted magnetically, but it's going to be at a much lower frequency. The induction charging has a frequency of 40KHz while this would be more like 60Hz.

    • OK, so it can double as a garage heater in winter. However, in the snowier parts of the country (i.e. NOT Vancouver and its suburbs), this will not be appreciated for outdoor use - lots of meltwater turning into smooth ice...

      This can easily work outdoors. Both magnet sets can be encased in a non conductive cover when outdoors, so no moving parts will be exposed. I have worked with something very close to this device for charging. Wish I had thought of this first!

    • Parking lots are normally plowed to be clear of snow. If the space was not plowed than how would the car park there to charge anyway? Your post does not make a lot of sense when you think about it.

      • by cynyr (703126)

        because you can park on top of 4"-8" of snow just fine even if the lot isn't plowed.

      • Parking lots are normally plowed to be clear of snow. If the space was not plowed than how would the car park there to charge anyway?

        Just go to Ontario, or Maine, or Finland, or Sweden. There's lots of snow in winter, and parking lots (although plowed quite often) are rarely free of it. Cars drive on snow and can drive on quite a depth of packed snow or a few inches of unpacked snow. In fact, driving on snow is not at all difficult, especially with proper winter tires or even just with all-season radials, and nor is parking on snow.

        Your post does not make a lot of sense when you think about it.

        Actually, your response indicates that you have much to learn about driving in cold climates. Perhaps yo

    • by TheLink (130905)

      OK, so it can double as a garage heater in winter.

      I wonder if it can double as a hard disk drive eraser too ;).

      Hopefully it won't accidentally spin objects and cause damage.

  • by Shavano (2541114) on Sunday October 28, 2012 @10:43AM (#41796721)
    Not if I'm paying for the electricity. I don't really feel like paying 10% extra to charge my car for the convenience of not having to plug it in. How much more does this charging system cost and how much does it add to my car's weight? Qualitatively, let's estimate that as "too much."
    • by trout007 (975317)

      I think it would be more useful for public charging places. Less potential for vandalism is its embedded in the road.

      • Re: (Score:3, Interesting)

        by vlm (69642)

        Less potential for vandalism is its embedded in the road.

        LOL so you think. Give the 4chan-ers a box full of BBs or ball bearings and watch the fun begin. Depending on rotational freq etc this could be pretty exciting or dangerous.

        Foreign conductive bodies are the bane of high power wireless charging. Womens fashion shoes with a conductive ring, finger rings like wedding rings, all issues with high power chargers. Even bycycle and motorcycle wheels are round enough to act as a shorted turn. Using rotating magnet power is no less of a hassle.

        • by ljw1004 (764174)

          Wouldn't it only be ferrous rings that are a problem? Wedding rings would presumably be things like gold or paladium instead?

          • Look up eddy currents and inductive heating
          • All conductive rings would have current induced in them. This will cause them to heat up _and_ generate their own magnetic field, which will cause torques but no net force.

    • by timeOday (582209)
      90% may not be good enough if a plug is a convenient alternative. If you're taking an efficiency hit, might as well use it to enable something new. How about this: line up magnets under the road to charge cars as they move along. (Ideally the chargers would be powered by solar panels in the median, or in the road itself).
      • by Shavano (2541114)

        90% may not be good enough if a plug is a convenient alternative. If you're taking an efficiency hit, might as well use it to enable something new. How about this: line up magnets under the road to charge cars as they move along. (Ideally the chargers would be powered by solar panels in the median, or in the road itself).

        That would be a good idea if it weren't so obviously unworkable and wouldn't slow down every car on the road and cost a million times more than a stationary charger.

      • by nukenerd (172703)
        timeOday wrote :-

        90% may not be good enough if a plug is a convenient alternative.

        You are dammed right it isn't. In fact it is totally unacceptable. Think of it as a 10% price hike (for which UK elecricity supply companies are taking huge flak right now www.theregister.co.uk/2012/10/26/edf_energy_price_rises/). I cannot imagine anyone in their right mind and able body would pay an extra 10% for a substantial chunk of fuel just to avoid putting a lead in a socket. There are many chores in my life that are a PITA, but plugging a lead into a car would come about nowhere

        • by timeOday (582209)

          I cannot imagine anyone in their right mind and able body would pay an extra 10% for a substantial chunk of fuel just to avoid putting a lead in a socket.

          I might not either, but a lot of people routinely spend twice (i.e. 100% more) than they need to on fuel, just to boost their ego or have a smoother ride or more elbow room. They buy bottled water and don't bother turning off the heat when they're not home, too.

          Keep talking : you have nearly invented a perpetual motion machine of the first kind.

          Huh?

    • by AmiMoJo (196126) * <{ten.3dlrow} {ta} {ojom}> on Sunday October 28, 2012 @10:57AM (#41796851) Homepage

      Tesla Motors is deploying solar power charging stations. When the fuel is free the 10% loss is worth it for the simplicity of having a car park where every space automatically re-charges your car, included in the cost of the ticket.

      • by Shavano (2541114)
        That's a promotion. The power is not free because somebody has to pay for the installation.
    • by CastrTroy (595695) on Sunday October 28, 2012 @11:03AM (#41796903) Homepage
      Especially disappointing coming from Canada where plug our gas powered cars in during the winter anyway. Is it seriously that hard to plug in your car? Why not just build in some sort of robotics and sensing system so that the charging station can maneuver the plug into the car if you are really that lazy.
    • Also wondering how carefully aligned one must park the car over the "charger". Would all car models have to have an identical physical "receiver"? You'll have a hard time getting every manufacturer to agree on that. You can't even get a common cell phone charger agreed on.
      • by Shavano (2541114)
        you could design such a machine to align itself with the car, but that adds cost and complexity. I'm sure their prototype has no such provision. Also, what happens when you drive this car over a chunk of loose steel? It winds up stuck to the bottom of your car, no?
  • It involves a spinning magnet beneath the parked vehicle which turns another magnet in the underside of the car.

    Oh wow, it's a jumbo Magnetic Stir Plate [wikipedia.org]! Perfect for that 1000L Erlenmeyer Flask in your garage.

  • F-Zero (Score:4, Insightful)

    by Anonymous Coward on Sunday October 28, 2012 @10:47AM (#41796755)

    I have visions of the recharge lane.

    • Re:F-Zero (Score:4, Interesting)

      by Latentius (2557506) on Sunday October 28, 2012 @10:52AM (#41796813)

      Joking aside, that's not a half-bad idea. Even if we're talking about the non-magnetic forms of wireless power transmission, it could be possible in the distant future to embed the technology in our highways and have it powered by roadside solar panels, etc.

      • by Shavano (2541114)
        Yeah, I'll only have to drive in that lane for four hours every day while it inductively slows down my car.
        • But you wouldn't drive in the lane to get a full power-up; you'd only need enough to maintain cruising speed, which is a lot less power. Or even less than that, if you're just looking for any sort of external boost to make up for the inherent issues with trying to store power onboard.

          As for slowing the car down, that may be the case with a magnetic charger, but I'm not sure about inductive coupling--I'll defer to the EEs to make a ruling on that one.

          • by Jmc23 (2353706)
            What would be the point? If you're going to go as far to imbed tech into the road, then just line the highways with superconductors, and have light weight floating cars. hi tech bumper cars, crashing would be fun :)
        • by AK Marc (707885)
          You are right, and wrong. It could just as easily be set up to pull your car faster, not slow it. So you could use the spinning electromagnet stuff to move the car, rather than charge the car, and only charge cars if the speeds are s slow that they wouldn't be slowed (charge in stop and go, push in high-speed).
  • by mark-t (151149) <markt@ l y n x.bc.ca> on Sunday October 28, 2012 @10:49AM (#41796773) Journal
    Not that I'm complaining... I'm just a bit surprised. News for nerds north of the 49th.... If this was November, I'd suspect some sort of alliteration joke to be forthcoming.
  • OK now go get a snow saucer and tape a few strong magnets on some inside edges. go out to the parking lot. Put a quarter into the meter, sit, and spiiiiiin !

  • Existing tech (Score:5, Informative)

    by trout007 (975317) on Sunday October 28, 2012 @10:55AM (#41796829)

    This is used all of the time in pumps where you don't want a dynamic seal. You have permanent magnets spun by a motor and inside a sealed case the pump is coupled by a magnetic field.

    http://www.proconpumps.com/brands/Magnetically-Coupled-Pump-(Sealless).html [proconpumps.com]

    • by Prune (557140)
      A similar setup is used in rotating anode X-ray tubes (the most common type). The anode is rotated to distribute the damage from the high energy impact of the electron beam and improve heatsinking ability; however, the tube must be completely sealed to maintain the high vacuum necessary for operation, so the rotor, unlike typical electric motors that use coils for field generation powered by brushes [wikipedia.org], uses permanent magnets instead (brushes would also cause contamination of the vacuum due to mechanical ablat
  • Well, I'm impressed that effort is being shown in the electric car 'movement', even if this isn't the best choice in re-charging.. We've come a long way since the 1990's when big oil killed off the EV1. http://en.m.wikipedia.org/wiki/General_Motors_EV1 [wikipedia.org]

    And now that battery powered vehicles are becoming more main-stream, we can use oil when and where it's more useful (planes, trucking, remote power generating, etc.)

  • by K. S. Kyosuke (729550) on Sunday October 28, 2012 @11:05AM (#41796917)
    Why not make it a two-part transformer? You'd just have a spinning magnetic field with no moving parts. You would also eliminate two extra rotary electrical machines (the motor in the charger and the generator in the car).
    • Read the article. The researchers are aware of that. They are also aware that there are lots of 'OMG EMF!!!' people who still think that wifi is cooking their brains. This magnetomechanical charger's big selling point is that there is no high-frequency magnetic field to scare people.
      • Re: (Score:2, Insightful)

        by HornWumpus (783565)

        In what world is it a good idea to encourage idiots?

        We need to be publicly humiliating these people (public double blind testing) not wasting time and money building nonsensical things to not actually work around the non-issues they have their panties in a bunch over.

        • by Prune (557140)
          Double-blind testing spread over several decades is immensely expensive, and that is a timescale beyond the horizon of interest for modern industry.
      • But *why* would you employ a high frequency magnetic field? You most likely don't need anything beyond 20 kHz. And with a proper core, you can keep most (virtually all) of the magnetic flux within the core, even with a dielectric/paramagnetic gap between the two parts of the core. And transformers are certainly more efficient than 90%.
        • Anything less than 20KHz is likely to produce audible noise.
      • by nukenerd (172703)
        So these people are planning to sit in their cars all night while they are charged? If these idiots are that paranoid, why can't they just get out the car and plug it in instead? Why do we waste time on these people?
  • by slick7 (1703596) on Sunday October 28, 2012 @11:08AM (#41796937)
    Thank you, Nikola Tesla.
    • Not my first thought, Nikola Tesla did come up with it, yet the article makes no such claim:

      FTA:
      "Wireless charging has been a much sought-after technical solution for everything from cell phones to electric cars,"

      Yet you don't need to charge the damn things just have a transmitter to power them; and
      what blocked Nikola Tesla from successfully showing it was possible.

      Money never interested Tesla, only cared for what it took to build his "stuff". Tesla's
      plan was free power for everybody at any place in the wor

  • by Shavano (2541114) on Sunday October 28, 2012 @11:08AM (#41796943)
    I knew if I waited long enough I would get my wind-up toys back. But why aren't they using a big spring?
  • by mtrachtenberg (67780) on Sunday October 28, 2012 @11:31AM (#41797083) Homepage

    Brilliant. I'd make a teensy change. Replace the spinning magnet outside the car with a cable, and replace the spinning magnet and generator in the car's underbody with a plug. Run power through the cable to the plug, but only after there's been a handshake between the cable and the plug. Use the equipment that would spin the magnets to establish a physical connection between the cable and the plug.

    I think the efficiency of this, compared to old techniques, will be closer to 100% of existing efficiency than to 90%.

    • by istartedi (132515)

      Dude! I think you're on to something but let's take it a step further. We don't really want electricity in the car. We want the car to go places. So take the spinning motion, and stretch it out along a cable. Then, have the car grab the cable. Then you've got the motion transferred directly to the car via cable, without any electricity involved. There's just a cable and a car. We could call it a "cable-car". I bet it would really safe [go.com] since there's no electro-magnetic waves at all anywhere. Just m

    • by Jmc23 (2353706)
      Seriously though, pushing a button when your car is parked, or having a pressure switches underneath the tires that activate current in the plug, creating a carefully designed magnetic field that attracts the plug into the receptacle on the bottom of the car would be so much cooler(literally). Then when fully charged, the field breaks, and the plug disengages recoils automatically and mechanically so no electricity needed.
      • Just find a way to do that so the system is entirely sealed from water and dust, is able to be driven over and still work when misaligned.
  • I foresee losses due to eddy currents induced in the chassis of many cars. Because metal (usually steel) is the predominant chassis material currently and in the foreseeable future.

    • by Prune (557140)
      One could do things such as wrap parts of the bottom chassis with mu metal and add additional mu metal to direct the field lines towards the receiver (mu metal in your hard drive make magnetic field leakage essentially a non-issue). Mu metal is not that expensive even in quantity compared to what an electric car costs.
  • I think I would go with the cable myself, you would also save a few thousand on car and wireless transmitter as well I imagine.

    • by drinkypoo (153816)

      I knew I could scroll and find this. This is a crappy, stupid idea. What we need is not inductive charging while sitting still, but inductive charging while almost sitting still... during the commute. In places where cars regularly go slowly there should be inductive charging systems, and some sort of micropayment system should permit rolling charging. That's where inductive charging actually becomes useful. While you're sitting still, there's no reason not to plug in a cable, and inductive charging systems

  • So does this mean that you would need to do a 100% perfect parking job to get the 90%, and if you were off by a few inches it would go way down, be off by a half a foot and it would not work at all?
    It seems to me that parking the car perfectly would be significantly more work than just getting it within reach of a cable.

  • Wireless power has been done before.

    A more complicated solution involving inductive nearfield power was developed by GE for electric cars around 5 years ago, and they've demonstrated a near finished commercial product, asserted it was safe that would even work underwater, and wouldn't short.

    Yes, there was a slashdot article, no I can't find it. They tried selling it to san franciso, but they opted out, as the unknown effects of high power RF.
    • by Prune (557140)
      Well, this case is purely magnetic regime near field and the low frequency means that far field EM isn't an issue until kilometers out from the system, by when it has been falling off quadratically for a while--and only the 10% leakage they mention as well.
  • You would need some pretty strong magnets, I would think. Strong magnetic fields can be very hazardous to people with pacemakers.

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