Cross-Canada by Ebike

[billvon]

Hey Justin! How do U run all those different Ah batts in parallel?

Not to answer for Justin, but on my bike I just run the 7ah Ni-MH and the 10ah lipo's in parallel. They share power pretty effectively; no diodes required. I can even charge them that way.

 

[EDWIN]

HELLO JUSTIN
If you need a place to recharge and sleep.I have spare room you can use. I am in central Winnipeg so it should not take you to far of your route.
edwin

 

[The7]

A group of seniors with average age of 64 are doing their cross-Canada by bicycles in nearly three months since 2008 May 26.

Justin, you may have to wait for another thirty plus years to beat them.

 

[The7]

Hey Justin! How do U run all those different Ah batts in parallel? U must use Shottkys, but dont u get say when the small packs are fully drained?
otherDoc

Don't think that the re-gen will function if there is a diode in series with the battery because the diode will block the charging current.

Maybe Justin have his geniuos way of doing so!?

 

[MitchJi]

A big part of this trip is to field test a number of components in a seriously demanding manner, and the regen motor controller is chief among them. This unit is quite a few years in the making, I think I'm at PCB revision number 12 or 13 now.

There are a few things this controller does which have been IMO long overdue in the ebike scene:
1) Programmable limits : All of the controller parameters such as maximum battery current, maximum motor current, low voltage cutoff, max regen voltage etc. can be set to whatever value you like within the limits of the controller. With this 6 mosfet version, the battery current limit can be set from 0 - 30 amps, the motor current limit can be set from 0 - 45 amps.
2) Completely Waterproof: The entire controller is potted in epoxy so there is simply no possibility even of water damage. It can be run entirely submersed, in fact the controller would like that for the great heatsinking.
3) Small Size: This thing is about 1/10th the size of the Crystalyte 35A motor controllers so it can actually mount discretely on the bicycle.
4) Proportional Regen: When the regen switch is activated, then the throttle controls the intensity of the regen braking. The regenerative braking is motor current (hence torque) regulated, and you can set the maximum regen motor current in software.
5) Pulse by Pulse Current Limiting: You can short the output motor leads and run the controller full throttle and not blow a mosfet. Nice feature to have when the axle spins out and severs all the motor leads.
6) Current Throttle: The throttle input directly controls the battery current and hence the vehicle power. If you have the battery current limit programmed to say 20A, and ride half throttle, the controller will deliver 10A of power regardless of your speed.
7) Sensored and Sensorless: If there is a hall cable connected it will run as a sensored motor controller, if there are no hall signals present it operates sensorlessly. If the hall senor was initially connected, and then fails in the middle of your ride, the controller will detect this and switch over to sensorless mode without loosing a beat. I don't really need to say much more for people to know what this means for reliability!
8.) Overtemperature Protection: Rather than shutting down when the controller gets hot and leave you stranded on a hill, the controller automatically scales back the motor current limit value as the heatsink warms up, so it will protect itself from getting too hot while at the same time never cutting out completely.

There are a few more things too, but I think that sums up the important ones.

Hi Justin,

I hope you are enjoying your trip! Please drive safely!

No hurry on responding to the following, please wait until its convenient to reply.

It would be nice (IMO) if there were (like the Heinzmann) Overtemperature protection for the motor as well as the controller. Users could mount a temperature sensor on the motor and there could be a plug for it on the controller plus the ability to adjust the settings.

Cruise control would be nice also.

Can you give us a ball park estimate of when it might be available?

Two more controller related questions (if someone other than Justin knows the answers and wants to reply please do so):
Does Sensorless (#7) mean this would work with RC motors?

I don't understand the implications of Current Throttle (#6). If someone would explain this I would appreciate it.

Once again have a great time (if you decide to return via the S. F. Bay Area please let us know).

 

[justin_le]

I would like to know all the bike and non-bike related supplys that you have taken with you for the trip.
bike tools, spare tubes,parts, bike lock? etc

I've got all the standard fair of bike repair parts, plus a lot of ebike specific stuff like a multimeter, soldering iron, spare connectors and wiring etc. Non bike stuff is just a sleeping bag, a Hennessey Hammock, and a few changes of clothes.

Have you had any flats? Do you think your original tires will last?

I had one unexpected flat early on, there was nothing that punctured the tire but the tube got a hole on the inside that is against the rim, which was due presumably to improperly set rim tape which allowed the sharp edge of a nipple hole to be exposed. Since then the mechanic at the Power-In-Motion store in Calgary kindly re-outfit the wheels with Schwalbe Marathon Plus tires and these puncture resistance inner tubes that are like 1/8" thick, so right now the tires are nearly bullet-proof.

How are you getting back to Vancouver with the bike? Be careful of cannibalism if you take Greyhound back.
What are your plans if your bike irrepairably breaks down in the middle of nowhere?

The tentative plan at the moment is to take the train back to Vancouver, gives me a few days of rest to reflect on everything. The bike will be taken apart in Halifax and I'll only be bringing the essentials back with me, like the batteries, hub motor, and Xtracycle parts.

As far as irreparable breakdowns, that'd be part of the adventure! I can't imagine many things that would stop me for more than a day or two. Bicycles aren't that complicated. -Justin

 

[justin_le]

Are there any news about the new tiny controller?
How does it perform?

I'm quite pleased that so far the little controller has been doing just fine. I still get a bit nervous drawing a continuous 30A on long ascents, but the worst of those are over and right now on the prairies well it's pretty easy going for all systems involved.

Sounds like a great little controller! Have you considered adding phase advance? With phase advance I think you'd have a controller that could do anything.

Phase advance is really easy to do, but it doesn't make any improvement with the low commutation frequency ebike hub motors (unless you consider reducing the efficiency and increasing current draw an improvement). That's more something that comes into play with the 10,000+ rpm RC motors.

It would be nice (IMO) if there were (like the Heinzmann) Overtemperature protection for the motor as well as the controller. Users could mount a temperature sensor on the motor and there could be a plug for it on the controller plus the ability to adjust the settings.

I've thought about that, but it's not so easy to retrofit a temperature sensor inside a hub motor, since the wiring needs to go through the axle and generally there isn't room for anything more beyond the phase and hall leads that already occupy that space. This is especially true with the common practice now of having the cable run through a hollow in the center of the axle, rather than a larger slot on the slide like Crystalyte.

With proper motor current limiting that this controller has, there really shouldn't be any need to have a temperature sensor inside the hub. Both the controller and motor are going to be heated by the same currents, and a temperature rollback on the controller overheating will also limit the motor heating. As the hub motors have considerably more thermal mass than the controllers, you are not likely to ever run into a situation where the motor is overheating and the controller isn't.

The heinzmann only has a bimetalic type of temperature switch, and the controller just cuts out when this is switched.

Two more controller related questions (if someone other than Justin knows the answers and wants to reply please do so):
Does Sensorless (#7) mean this would work with RC motors?

It means that it will work with brushless motors that don't have hall sensors. However, I did not design it for motors with really high commutation frequencies like RC motors. I haven't tested the limits yet, but I'd say an upper limit on the commutation frequency would be about 500Hz for sensorless operation. Take that number, multiply by 60, and divide by the number of poles in your motor to get an RPM value.

I don't understand the implications of Current Throttle (#6). If someone would explain this I would appreciate it.

In a typical ebike controller right now, if you apply the throttle part way from a stop, you'll get the full current limit of the controller flowing from the battery at first, then as you accellerate this current will go down until you hit your partial throttle cruising speed. If you then pedal the bike, the current will go down further, to zero amps, unless you press the throttle further.

With a current throttle, if you applied it part way, the current that flows from the battery pack would be in direct proportion to how far you are pressing the throttle, regardless of your speed, until you are going fast enough that the current is back-emf limited.

Chances to launch it ? Price? I want two of them asap

Can you give us a ball park estimate of when it might be available?

Just to clarify, the controller is still just a pet project of mine, so don't anyone hold their breath for this to show up at an ebike shop near you. There aren't any plans at all to manufacture controllers for resale at this point, though that may change in the future.

-Justin

 

[justin_le]

We'll I've come pretty far:



But boy when you look at the big picture, there is there still a long way to go!



Trip stats to date are in the attached spreadsheet. Will be in Regina on Sunday.

The rolling hills and strong winds here in Sasakatchewan have actually given me pretty poor energy usage, so I'm generally only able to budget about 90km from a full charge, using more like 14Wh/km instead of the 12 I was getting through BC. The complete trip statistics are attached, I've used exactly $2.00 worth of electricity and covered some 1811km. It's actually going to be pretty close to get all the way on $10.

Justin

 

[Doctorbass]

Justin, Quebec is waiting for you here!

see that article in our newspaper... oh! they talk about you at the end of this article! :wink:

http://veloptimum.net/velonouvelles/8/ART/8aout/Soleil16p.html

Doc

 

[mikereidis]

In a typical ebike controller right now, if you apply the throttle part way from a stop, you'll get the full current limit of the controller flowing from the battery at first, then as you accellerate this current will go down until you hit your partial throttle cruising speed. If you then pedal the bike, the current will go down further, to zero amps, unless you press the throttle further.

With a current throttle, if you applied it part way, the current that flows from the battery pack would be in direct proportion to how far you are pressing the throttle, regardless of your speed, until you are going fast enough that the current is back-emf limited.
-Justin

It's not entirely clear from this explanation, but my understanding is that a traditional throttle is a power control. Ignoring aerodynamics, maintaining a constant torque/acceleration requires turning the throttle higher as your speed increases. This can be annoying, IMO.

With a current throttle, the position more or less sets the torque / acceleration. In theory, in a perfectly 100% efficient world with no wind resistance or other exponential resistances, a constant current will produce a fixed torque and acceleration. I.E your speed would increase forever, like a craft in space. In the real world of course, besides aerodynamics, the motor back EMF will rise towards the battery voltage and current flow will decline.

But at low speeds, current throttle = torque control and normal throttle = power control, more or less. I'm sure someone will correct any misunderstandings I have.

How well is this current control working on your trip ? Does it make it easier to maintain speed without adjusting the throttle ?

So Justin: Does it look like you'll be in Southern Ontario by Labor Day ? Or a bit later ? By rough eyeing of your route it looks like your 40% here already, but I imagine your speeds have increased on flatter land ?

 

[billvon]

Phase advance is really easy to do, but it doesn't make any improvement with the low commutation frequency ebike hub motors (unless you consider reducing the efficiency and increasing current draw an improvement).

Yeah, I was thinking of it as a way to choose a motor with a base speed that allows you to cruise efficiently at a lower speed (say, 20mph) and then occasionally use phase advance to get some extra speed for intersections etc. Basically a temporary increase in top speed.

 

[justin_le]

With a current throttle, the position more or less sets the torque / acceleration. In theory, in a perfectly 100% efficient world with no wind resistance or other exponential resistances, a constant current will produce a fixed torque and acceleration. I.E your speed would increase forever, like a craft in space. In the real world of course, besides aerodynamics, the motor back EMF will rise towards the battery voltage and current flow will decline.
But at low speeds, current throttle = torque control and normal throttle = power control, more or less. I'm sure someone will correct any misunderstandings I have.

Hi Mike, to correct your misunderstanding:
PWM Throttle (Crystalyte and virtually all chinese ebikes) = Crude open-loop Speed Control
Battery Current Throttle (what my controller does) = Power Control
Motor Current Throttle (what industrial servo controllers do) = Torque Control

How well is this current control working on your trip ? Does it make it easier to maintain speed without adjusting the throttle ?

No, what it does is make it much easier to maintain my battery current draw without adjusting the throttle. My speed will then vary according to the grade, wind, and pedal input, but I have great control over how rapidly the pack is being drained which is the main concern on a trip like this. Some people might greatly prefer the feel of a PWM throttle or a torque throttle, or perhaps a closed-loop speed control throttle, and there is no reason with a programmable controller that it couldn't do all of these based on a user setting.

Justin

 

[justin_le]

Phase advance is really easy to do, but it doesn't make any improvement with the low commutation frequency ebike hub motors (unless you consider reducing the efficiency and increasing current draw an improvement).

Yeah, I was thinking of it as a way to choose a motor with a base speed that allows you to cruise efficiently at a lower speed (say, 20mph) and then occasionally use phase advance to get some extra speed for intersections etc. Basically a temporary increase in top speed.

Well, in that situation it is something worth thinking about and I might play around with when I get back. First though we'd need to find a throttle with a "TURBO" button on it!

Justin

 

[Zoot Katz]

. . .
How well is this current control working on your trip ? Does it make it easier to maintain speed without adjusting the throttle ?. . .

No, what it does is make it much easier to maintain my battery current draw without adjusting the throttle. My speed will then vary according to the grade, wind, and pedal input, but I have great control over how rapidly the pack is being drained which is the main concern on a trip like this. Some people might greatly prefer the feel of a PWM throttle or a torque throttle, or perhaps a closed-loop speed control throttle, and there is no reason with a programmable controller that it couldn't do all of these based on a user setting.

Justin

To quote yourself "Furthermore, the Cycle Analyst has the ability to over-ride the user's throttle and regulate the power delivered to the motor, turning an otherwise dumb ebike into an intelligent device with a user programmable speed limit, current limit, and low voltage cutout"

Does not the programablity of a controller become moot with a CA installed?

Ain't those prarie night skies something?
Intorspection is hard to avoid crossing a continent at bike speeds.
Drink lots of water. Gods' speed.

 

[mikereidis]

How well is this current control working on your trip ? Does it make it easier to maintain speed without adjusting the throttle ?

No, what it does is make it much easier to maintain my battery current draw without adjusting the throttle. My speed will then vary according to the grade, wind, and pedal input, but I have great control over how rapidly the pack is being drained which is the main concern on a trip like this. Some people might greatly prefer the feel of a PWM throttle or a torque throttle, or perhaps a closed-loop speed control throttle, and there is no reason with a programmable controller that it couldn't do all of these based on a user setting.

Justin

Cool, thanks. Range is my primary concern right now, so I'm very interested. I want to be able to plan my routes based on my current battery capacity, and a current control might give me more, and more consistent, kilometres per complete charge.

I took my 2 kids on a trailer on my regular 44 KM route today. 350 pounds total. I had to help pedal up hills because the trip did in my "real" 600 watt hour LiMn pack. Previously I've ran that route using only 400 watt hours (15-25 KMH, except a few 30 KMH) with total weight of 245 pounds.

In situations like this I'd be better off losing some speed on the easy parts and saving watt hours for the worst part at the end which is largely uphill, with some 10% sections. Not fun with 173 lbs of me, 72 of bike and 105 of kids, trailer and minimal (4 lbs) cargo. (On a recumbent, at age 45 out of shapish, asthma symptoms, smoker...)

Thought I heard that a current throttle might be as simple a mod as adding a pot to the current limiting circuit. Hmmm, two throttles...

 

[justin_le]

To quote yourself "Furthermore, the Cycle Analyst has the ability to over-ride the user's throttle and regulate the power delivered to the motor, turning an otherwise dumb ebike into an intelligent device with a user programmable speed limit, current limit, and low voltage cutout"

Does not the programablity of a controller become moot with a CA installed?

Yes, or more the other way around. The CA is a display device that was made intelligent only because the existing stock of motor controllers were dumb. However, it makes more sense from an engineering design perspective to have an intelligent motor controller, and a dumb display device, (which is how things will be in the future if I have my way.)

Ain't those prarie night skies something?
Intorspection is hard to avoid crossing a continent at bike speeds.

The Prairie skies are pretty special, especially last week when there were meteor showers and I was seeing shooting stars everywhere I looked, or maybe I was just a bit delusional riding my bike at 3am. What is certainly for real are the prairie insects though. Big grass hoppers that jump in your path and smack me moving at 40kph with quite a loud crack. At night you can see them and the moths really clearly with the bike lights, and my head is sometimes moving left - right - left - right, dodging the various illuminated bugs I see streaking past. Who needs introspection when you have this kind of action!?

-Justin

 

[justin_le]

OK, so lesson about parallel batteries. I mentioned earlier that I had them all connected in parallel without diodes both for discharging AND charging. Normally this isn't advised, as charging a NiMH or NiCad pack with a CC/CV charger results in either a not fully charged pack or a destroyed pack, so when I did this I stuck around and was there to unplug the chargers when the requisit amp-hours were back in, OR I separated the parallel pack connection between the NiCads and the lithiums if I was leaving them alone, so each was only connected to the appropriate charger.

However, I noticed that what would happen if I didn't do this is that the BMS would cut the charging out on the lithium pack once it was fully charged, and this resulted in a small drop in the overal battery pack voltage once the charging suddenly ceased, and that in turn caused the -dV/dt cutout of the NiCad charger, so both chargers would shut off once the lithiums were topped up. Neat. This happened the last 3 times in a row so I got a bit complacent about leaving them alone. I left them connected when I charged up last night. Everything seemed fine this morning but then the pack went flat at just 29Ah, before I quite made it into Regina, leaving me huffing and puffing for the last stretch into the city. Only then did I investigate the batteries and noticed this:



So, even people who really think they know what they are doing screw up . This one time the Lithium charger did not turn green before the NiCad went to the negative voltage drop region, and as a result it got overcharged and totally cooked.


Oops. So down to 29Ah and only lithiums now.

 

[monster]

bummer dude! what are you gonna do now? do you have any support vehicles like in the tour de france?
why did you have to cut corners on this? did a charger brake on you or something?

 

[justin_le]

Justin, Quebec is waiting for you here!
see that article in our newspaper... oh! they talk about you at the end of this article! :wink:
http://veloptimum.net/velonouvelles/8/ART/8aout/Soleil16p.html

Doc, You are awesomes! I can't wait to get to Quebec, it's just there's this really big thing called Ontario in the way

I'll have more postings to make regarding media stuff later, but for now time to go find a place to camp out before the sun rises -Justin

 

[fechter]

You're lucky those NiCds didn't go ballistic or catch on fire.

Seems to me Doc has a lot of batteries around his place. Maybe he can set you up with a pack for the rest of your trip.

 

[EDWIN]

Hello Justin
Did you forget Manitoba?
edwin

 

[Perfesser]

Hi Justin.
Dang. I know how it feels. I hate it when my contraptions go "boing" when I thought I had it all figured out.
Anyhoo, I can put a pack together for you and have it in Winnipeg by Wed AM if you give me the sign (before 9PM Monday night). It will be Ni-Cad, and balanced with at least 2 cycles (remember the explosion on my trike at the VEVA show?).

There's plenty of protein in them Manatoba grasshoppers. You can shave some expense off your food budget by not dodging them. Spit out the head though.
-Karl

 

[steveo]

Justin, Quebec is waiting for you here!
see that article in our newspaper... oh! they talk about you at the end of this article! :wink:
http://veloptimum.net/velonouvelles/8/ART/8aout/Soleil16p.html

Doc, You are awesomes! I can't wait to get to Quebec, it's just there's this really big thing called Ontario in the way

I'll have more postings to make regarding media stuff later, but for now time to go find a place to camp out before the sun rises -Justin

Hey ..

I'm there lol

 

[Doctorbass]

Justin, Quebec is waiting for you here!
see that article in our newspaper... oh! they talk about you at the end of this article! :wink:
http://veloptimum.net/velonouvelles/8/ART/8aout/Soleil16p.html

Doc, You are awesomes! I can't wait to get to Quebec, it's just there's this really big thing called Ontario in the way

I'll have more postings to make regarding media stuff later, but for now time to go find a place to camp out before the sun rises -Justin

Hey Justin, the newspaper journalist asked me to know when you will arrive to Quebec city.. He want an interview with you for another article !!! I hope you'll have few minutes for that too! And dont forget.. I have a bed and place for lunch !

Doc

 

[solarbbq2003]

go justin, you crazy son of a *****, you'll solve it somehow