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The Halbach Disc Motor Ebike Project
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safe
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It's a difficult challenge... there is no doubt... but the one thing I realized this winter is that had I built the first incarnation I had in mind it would not have worked the way I wanted.
On endless sphere there are countless attempts to build motors only to see people revert back to the tried and true of hub motors or borrowed RC motors. No one is original.
The CSIRO motor costs $10K and is widely respected as the most technologically advanced motor in existence. It wins the Solar Races all the time since the efficiency is about 95% across a wide powerband.
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Think of the options today:
Hub motor - Powerful, but 25 lbs on the rear wheel, that's just stupid.
RC motor - Complicated to assemble because there are so many elements to put together. Standard ESC's are junk because sensorless doesn't work well on an electric bike. Efficiency losses due to the geardowns mean that it's good for power, but not as good for efficiency. There are just too many moving parts.
...so the Halbach Disc motor concept (totally new and it's uncertain if it will work well the way I'm trying it) could be the thing that ebikes are missing. The Halbach Disc motor is efficient, weighs a scant few pounds, it will be possible to (eventually) build them so that they fit on existing cassette type rear hubs so they are compatible with common bike components. All these things (if it all works) translates into something new, valuable, and game changing.
I'd rather take my time and do it right than rush in and screw it up.
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My hope is that racing "settles" on either 1K or 2K in the future. If my gamble is correct and limited power ebike racing is the way it goes then I'm actually making progress while all the RC work goes down the drain. If there is a power limit in racing the RC concept falls flat because it's core aspiration is power, not efficiency. Not that the efficiency is all that bad, but if the power limit is 1K or 2K it's ridiculous to be going through all the effort of all that geardown stuff.
The dumbest thing about all this power thinking is that years ago someone attached an Etek to an electric bike and right there you had all the power you needed. Power has been around all the time... but it's become sort of a "fashion statement" to get power in certain ways and people are naturally going to follow fashions because (most) people are very insecure and wanting to be accepted. So they follow the herd. What I'm doing is to reject the "group think" and think for myself instead. Somebody has to be original.
I simply reject the idea that the goal of motor building is more power. I want precisely a "certain amount" of power and I want it to be simple, low maintanence, efficient and light weight.
United States - 750 watt limit
Canada - 500 watt limit
Australia - 200 watt limit
Europe - 250 watt limit
...and human power is at best only 400 watts for any length of time.
Based on all this a racing league that is based on the 750 watt power output level (1K input) makes the most sense as an entry level racing league.
Don't worry... I'm fully dedicated to the project... but I also have house repairs that need doing too. I have a downstairs that needs to be built out this summer.
On endless sphere there are countless attempts to build motors only to see people revert back to the tried and true of hub motors or borrowed RC motors. No one is original.
The CSIRO motor costs $10K and is widely respected as the most technologically advanced motor in existence. It wins the Solar Races all the time since the efficiency is about 95% across a wide powerband.
-------------------------------
Think of the options today:
Hub motor - Powerful, but 25 lbs on the rear wheel, that's just stupid.
RC motor - Complicated to assemble because there are so many elements to put together. Standard ESC's are junk because sensorless doesn't work well on an electric bike. Efficiency losses due to the geardowns mean that it's good for power, but not as good for efficiency. There are just too many moving parts.
...so the Halbach Disc motor concept (totally new and it's uncertain if it will work well the way I'm trying it) could be the thing that ebikes are missing. The Halbach Disc motor is efficient, weighs a scant few pounds, it will be possible to (eventually) build them so that they fit on existing cassette type rear hubs so they are compatible with common bike components. All these things (if it all works) translates into something new, valuable, and game changing.
I'd rather take my time and do it right than rush in and screw it up.
----------------------------
My hope is that racing "settles" on either 1K or 2K in the future. If my gamble is correct and limited power ebike racing is the way it goes then I'm actually making progress while all the RC work goes down the drain. If there is a power limit in racing the RC concept falls flat because it's core aspiration is power, not efficiency. Not that the efficiency is all that bad, but if the power limit is 1K or 2K it's ridiculous to be going through all the effort of all that geardown stuff.
The dumbest thing about all this power thinking is that years ago someone attached an Etek to an electric bike and right there you had all the power you needed. Power has been around all the time... but it's become sort of a "fashion statement" to get power in certain ways and people are naturally going to follow fashions because (most) people are very insecure and wanting to be accepted. So they follow the herd. What I'm doing is to reject the "group think" and think for myself instead. Somebody has to be original.
I simply reject the idea that the goal of motor building is more power. I want precisely a "certain amount" of power and I want it to be simple, low maintanence, efficient and light weight.
United States - 750 watt limit
Canada - 500 watt limit
Australia - 200 watt limit
Europe - 250 watt limit
...and human power is at best only 400 watts for any length of time.
Based on all this a racing league that is based on the 750 watt power output level (1K input) makes the most sense as an entry level racing league.
Don't worry... I'm fully dedicated to the project... but I also have house repairs that need doing too. I have a downstairs that needs to be built out this summer.
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machiasmort
Active Member
"The dumbest thing about all this power thinking is that years ago someone attached an Etek to an electric bike and right there you had all the power you needed. Power has been around all the time... but it's become sort of a "fashion statement" to get power in certain ways and people are naturally going to follow fashions because (most) people are very insecure and wanting to be accepted. So they follow the herd. What I'm doing is to reject the "group think" and think for myself instead. Somebody has to be original."
1st thing you've said that has made sense to me.... Now your thinking!
I seen a UFO about 10yrs ago... An alternate energy does in fact exist... We just havn't tapped it yet! Maybe it's a way to use electricity? Without inovation there's limitation!
1st thing you've said that has made sense to me.... Now your thinking!
I seen a UFO about 10yrs ago... An alternate energy does in fact exist... We just havn't tapped it yet! Maybe it's a way to use electricity? Without inovation there's limitation!
safe
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The ebike world is suffering with a sort of "identity crisis" these days. People are not yet clear what the machines will look like and how they will perform. I'm not sure that for racing that the power limits will be set at exactly 1K and 2K, in fact, I can see a strong argument for 1K (beginner) and 5K (expert) because that would really separate the divisions and give a place for people that like powerful ebikes. The one thing that I'm pretty sure of is that unlimited power in ebike racing is going to force some other restriction by necessity because otherwise the bikes are going to just get more and more like motorcycles. In the ePower Challenge at Portland International Raceway they dealt with this by setting not a power limit but a battery limit. They have this device called the WHAM that meters the battery and when you hit "empty" based on the rules it cuts out... sort of like running out of gas. The problem with that type of rule is that it hurts the racing because people get focused on preserving "fuel" rather than trying to go fast.
With power restrictions in ebike racing the focus will change to efficiency, weight, handling and aerodynamics. (and of course rider skill and strategy)
This last week was a project time loss because my old bike broke and I went ahead and fixed it. There are probably 100 things I need to do on this house and am behind on because I've thrown so many hours into the ebiking... if I had a wife I'm sure she would have nagged me to get the chores done long ago, so not being married has been one of the driving forces in doing as much work as I have done.
Time spent so far on ebikes since 2006:
Researching or building bikes per week ~ 20+ hours (possibly twice this)
Weeks in a year - 52
Years building ebikes - 4
20 * 52 * 4 = 4160 hours so far ! (yikes)
With power restrictions in ebike racing the focus will change to efficiency, weight, handling and aerodynamics. (and of course rider skill and strategy)
This last week was a project time loss because my old bike broke and I went ahead and fixed it. There are probably 100 things I need to do on this house and am behind on because I've thrown so many hours into the ebiking... if I had a wife I'm sure she would have nagged me to get the chores done long ago, so not being married has been one of the driving forces in doing as much work as I have done.
Time spent so far on ebikes since 2006:
Researching or building bikes per week ~ 20+ hours (possibly twice this)
Weeks in a year - 52
Years building ebikes - 4
20 * 52 * 4 = 4160 hours so far ! (yikes)
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Safe your picture of an etek powered rackmount with low slung battery's is the prettiest e bike I have seen yet.
I may just build my version of that if I decide to go electric.
The LOCAL emission laws need to ban my 2 strokes first!
I think I have settled on a do able for me design.
A Rack mount etec , or clone, with side mount batteries on a full suspension bike.
If you substitute the electric motor for a gp460 you have the type of motorized bicycle I now build and prefer.
The driven sprocket can be either on the right or left side of the rear wheel in my designs.
I may just build my version of that if I decide to go electric.
The LOCAL emission laws need to ban my 2 strokes first!
I think I have settled on a do able for me design.
A Rack mount etec , or clone, with side mount batteries on a full suspension bike.
If you substitute the electric motor for a gp460 you have the type of motorized bicycle I now build and prefer.
The driven sprocket can be either on the right or left side of the rear wheel in my designs.
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safe
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I owned a Honda MB5 which was a 50cc GP Replica (with much lower quality parts, but the geometry was nice) and I used to love long 200 mile rides with that and only pay a dollar or two for gas. Unlike a lot of people in electric bikes I'm not an "eco snob" that looks down on the gas bikes... I like them too.
This Halbach Disc motor will eventually get done, but due to the complexity it's a big undertaking. I really don't even have a direct motor to copy because the CSIRO motor mounts the magnets next to the wheels and they are very large and strong. I'm trying to build something (while being aware of the physics involved) that is unique to the electric bike and is shaped in an unsual way. My Halbach Disc motor concept is to have an "open magnet array" and only a little less than half of it will be filled with the stator coils. That's just plain bizarre by most motor standards, but it's something that would cool very well and it moves the weight of the coils forward and up so that the bike will handle better. I'm essentially attempting to make a motor that would be ideal for someone concerned with cornering a lot... like on a go kart track.
We will see how it goes...
This Halbach Disc motor will eventually get done, but due to the complexity it's a big undertaking. I really don't even have a direct motor to copy because the CSIRO motor mounts the magnets next to the wheels and they are very large and strong. I'm trying to build something (while being aware of the physics involved) that is unique to the electric bike and is shaped in an unsual way. My Halbach Disc motor concept is to have an "open magnet array" and only a little less than half of it will be filled with the stator coils. That's just plain bizarre by most motor standards, but it's something that would cool very well and it moves the weight of the coils forward and up so that the bike will handle better. I'm essentially attempting to make a motor that would be ideal for someone concerned with cornering a lot... like on a go kart track.
We will see how it goes...
safe
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Infineon Controller With Halbach Disc Motor
Somehow I didn't "get the memo" this last winter about these low priced Infineon controllers as I was deeply into doing simulations using the FEMM program. At the time I was operating under the logic that since none of the controllers were doing phase current limiting (an error) that the selection of a Single Phase controller chip that did made the most sense.
Now I'm thinking:
"Hey... why not redesign the Halbach Disc motor so that it can use these Infineon controllers?"
...so I'm going to give that a go. These simualtions and spreadsheets take a loooong time to go through to arrive at a realistic profile of what the motor is going to do, so I'm going to need to study this for a while, but that's the most recent change in this project.
Out goes the Single Phase idea and in comes the (Three Phase) Infineon Programmable controller with all the bells and whistles I could ever want. This will significantly reduce the effort required to build the motor because now all I have to worry about is the motor part and not the controller... a big time savings.
However.... I'm going to need to run all the numbers to verify that this is going to produce a good result. (so it might not work as well, I don't know yet)
My main focus this summer is house repair, so the ebike stuff is all done in time in between... this is still such a massive undertaking for an individual (design and build an advanced motor from the ground up) that I have to be realistic that this won't be done in a day a week or a month. I'll be lucky to get it ready for next years race in Arizona.
Patience...
Somehow I didn't "get the memo" this last winter about these low priced Infineon controllers as I was deeply into doing simulations using the FEMM program. At the time I was operating under the logic that since none of the controllers were doing phase current limiting (an error) that the selection of a Single Phase controller chip that did made the most sense.
Now I'm thinking:
"Hey... why not redesign the Halbach Disc motor so that it can use these Infineon controllers?"
...so I'm going to give that a go. These simualtions and spreadsheets take a loooong time to go through to arrive at a realistic profile of what the motor is going to do, so I'm going to need to study this for a while, but that's the most recent change in this project.
Out goes the Single Phase idea and in comes the (Three Phase) Infineon Programmable controller with all the bells and whistles I could ever want. This will significantly reduce the effort required to build the motor because now all I have to worry about is the motor part and not the controller... a big time savings.
However.... I'm going to need to run all the numbers to verify that this is going to produce a good result. (so it might not work as well, I don't know yet)
My main focus this summer is house repair, so the ebike stuff is all done in time in between... this is still such a massive undertaking for an individual (design and build an advanced motor from the ground up) that I have to be realistic that this won't be done in a day a week or a month. I'll be lucky to get it ready for next years race in Arizona.
Patience...
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The Infineon sensored controller is one of the preferred setups on endless sphere.
http://endless-sphere.com/forums/viewtopic.php?f=2&t=8610
They are usually purchased from Ecrazyman on ebay or Knuckles on endless sphere.
http://stores.ebay.com/huaqiangnorthroad
What part number do you intend to use.
http://endless-sphere.com/forums/viewtopic.php?f=2&t=8610
They are usually purchased from Ecrazyman on ebay or Knuckles on endless sphere.
http://stores.ebay.com/huaqiangnorthroad
What part number do you intend to use.
safe
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I would be using a 48 volt 1000 watt brushless controller.
Did not see one on ebay right now, but I'm sure they are around.
No big hurry... the physical part of actually building the Halbach Disc motor will take some time. When it's done and ready for a controller I'll get into it more.
This stuff seems to evolve pretty fast, so you never know, there might be something else by then that is better. It's starting to feel like the computer industry where one days "high tech" is the next days "old stuff".
I can wait and let it all settle out...
Did not see one on ebay right now, but I'm sure they are around.
No big hurry... the physical part of actually building the Halbach Disc motor will take some time. When it's done and ready for a controller I'll get into it more.
This stuff seems to evolve pretty fast, so you never know, there might be something else by then that is better. It's starting to feel like the computer industry where one days "high tech" is the next days "old stuff".
I can wait and let it all settle out...
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