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[trikester]

That's a good video that Doc made. It explains a lot.

He didn't mention that the key has to be on for the switch in the battery to connect to the Sevcon. However, the video shows by the lights being on that his key is on. In the stock charging connector a signal line from the charger tells the battery to connect with the key off. On my 2013 battery modules there is no voltage present at the battery terminals when the key is off. It would seem that the charger signal could be created to connect the battery with the key off. Or: The internal battery switch is a mosFET. Maybe the charger could just connect to the battery through the body diodes of those switches. Termination voltage would need to take into account the drop across the diodes.

Trikester

[frodus]

I've been chatting with horizon for the past week or so and have dealer pricing because I'm a business. I'm looking into maybe getting a small one to play with. They seem pretty cool.... Even if they aren't that energy dense.

[dc5dd]

@frodus
the lowest seems to be 1kW which needs a DC/DC convertor.  According to Acorla if you use their modified horizon setup with nitrogen purge it could extend the life of the fuel cell by 2 to 3 times.  Which is very impressive but a 1kW from them cost about 1.5 to 2 times what horizon is charging. 

Can I ask what is dealer pricing?  According to the http://www.thehydrogencompany.com website a 1kW would cost $4.5k USD!

I'm getting a lot of good info here just need to dug more.

@BSDThw
Using the regenerative braking path is a great idea but the next question would be what about when the bike is off???  Need to look more into the what Doc did

@trikester
I'm thinking most on this forum are EE .  I need to find a minimal invasive way to do this without altering the internals of any of the major electrical components.  I think I have enough to dug with.  More questions soon.

[frodus]

Email me and I can get you initial some pricing. Its still not cheap but it's better.

[dc5dd]

@frodus
Do you have the equipment to charge the storage tanks?  I was thinking about this because it came up before and my initial thought was to purchase cylinders from Airgas or equivalent and if it pans out purchasing a reformer. 

[BSDThw]

Hi dc5dd

@BSDThw
Using the regenerative braking path is a great idea but the next question would be what about when the bike is off???  Need to look more into the what Doc did

If the bike is off the main relay is off => no connection to the battery! You should not power the Sevcon(Battery +/-) in "OFF"!

The Sevcon will pre-charge its internal capacitors normally. If you go to an "OFF" Sevcon you have a high inrush current to the Cs and than no connection to the Battery

I am testing the possibility to run the Sevcon and leave the rest of the bike "OFF" (Main relay will be switched by the Sevcon) but it will take 1-2 days before I have finished!

I will post if it works!

[frodus]

@frodus
Do you have the equipment to charge the storage tanks?  I was thinking about this because it came up before and my initial thought was to purchase cylinders from Airgas or equivalent and if it pans out purchasing a reformer.

I have absolutely nothing except pricing... Which is lower than retail because I own a business in Oregon. I don't yet sell them nor own one myself.

[BSDThw]

I will post if it works!

Did a 30-minute Test - charged the Battery with 45A and only powered on the Sevcon => main contactor. Worked pretty well but I will check out more.

If I have my charger-project done I will post detail information. (Still waiting on some parts)

[dc5dd]

@BSDThw

The 1kW fuel cell can only output power similar to the onboard charger so I don't think the profile you were talking about is not a problem.  Why not use the accessory charge connector or onboard charger connection and input the required trigger signal to connect the battery to the fuel cell/quick charger. 

If in fact it is as simple as that and for me the charging while the bike is off is solve (maybe).  On to when the bike is on 

On second thought BSDThw can the sevcon handle changes in VDC (35-48VDC) because the fuel cell will have these according to the power demand and this would allow me to do without the DC/DC converter for the 116VDC that I need to charge the battery pack.  Which is one less component to do with.  Man i need to read up on the sevcon controllers.

Does the BMS in the battery box monitor and equalize charge or the charger?  I would think it is the BMS inside the battery box.

[BSDThw]

With a 1KW fuel cell you can use the accessory charge connector I think I lost the common thread (1KW)

I didn't explain the Sevcon thing correct!
The Sevcon is not really involved in the charging, it will only activate the main contactor ( the relay you hear clicking when the bike is powered on )
If the relay is on you have an electric connection build for 420A, that is what I like to achieve.

You definitely need a DC/DC converter (the Sevcon will do nothing for you) , if you like to have it "perfect" you need a regulation that tries to set the fuel cell voltage to it's power maximum point. If you use a fixed ratio it should work but not at its best efficiency.

The BMS has an ON/OFF signal you should definitely use it to stop charging when the BMS monitor a "cell over-voltage" but how I understand this is a protection/fault situation. As I see with my Delta-Qs they reduce current before and the voltage will not top this level. The BMS can balance the cells but I have no information how and with what technology it work. I didn't monitor the charging very exact yet I don't know if there is a special signal for the balancing.   

BTW: I don't know the 2013 model,  I talk of my 2012 experience therefore keep in mind maybe it will be a bit different at the 2013!

[dc5dd]

Bummer I thought there was a chance it would work since the controller is responsible for regen and the fuel cell as well as the motor voltage fluctuates.  If you channnel the fuel cell back through the controller like the motor regen it can charge the battery???

[BSDThw]

Your Motor is a three phase system AC with 120° phase shift, your fuel cell is a DC system.

What would work for a DC source you can feed DC in your standard charger but also you need ~85V DC and have to look how to regulate your power correct.

You will like this, because solar and fuel cells are both DC-sources. I don't know how deep(VDC) the internal (Meanwells) at your 2013 can work.
http://electricmotorcycleforum.com/boards/index.php?topic=2897.msg14290#msg14290
http://electricmotorcycleforum.com/boards/index.php?topic=2897.msg14301#msg14301

BTW: If I understand you, you like to do this because you are interested to "play" with this technology?
I have never worked physically with fuel cells but have adapted a solar grid inverters to be powered from a fuel cell. It works as a "combined heat and power unit"  CHP there the immense heat loss is used too. - I understand if you like to "play" with such a system I often do things being not necessary/efficient eq a revers mode at my bike but it is fun.

[frodus]

It wouldn't matter since you're going through the fets and onto a DC bus. You're just rectifying the ac. Putting straight DC likely wouldn't matter.... But there may be safeguards in place to require an rpm input in order to rectify.

[dc5dd]

@BSDThw
Thanks for the info it'll take me a while to digest.  Yeah I'm having fun the cost is high but I'm do it in parts first the motorcycle and it to run out of warranty and then the fuel cell system, then finally to put it all together, especially since there are no major electrical changes to the bikes for 2014.  Early diopters always have a hard time because of the unknown I'm just tired of waiting for the commercial fuel cell motorcycles to come out besides this should be right up my alley.  You know it might be even easier if feeding the DC through the onboard charger will work.  I'm having trouble finding the DC/DC converter that will step up voltage from 35-48 to 116VDC, this way I'll only have to step it up to 85VDC (maybe) I'm not sure if that will be better?

@frodus
I'm thinking a electrical schematic of the sevcon and a understanding of the "safeguards" is in order here

[frodus]

Honestly, Good luck getting any circuit schematics from Sevcon. Sschematics wouldn't really help you (the power side of most inverters is pretty similar).... it would all be part of software control.... which you're just not going to get from any OEM. I know other manufacturers have done it with their inverters, but that doesn't mean the sevcon will. Is it possible? In hardware..... but software? Not so sure. There's external components required if you want the controller to boost voltage, and the controller firmware needs to support the flow of current through from the motor side into the battery. Also, This could NOT be done when the vehicle is running, so it does you no good, other than to have a way to charge it while stopped. You might as well use the charger as mentioned. I doubt the charger can be used at the same time your plugged in. Almost every production EV I've been in prevents driving off while plugged in.


My thinking is you are jumping in a little above your head and need to back off a bit. Going by your questioning about these bikes and the technology in them, you're new to it all. I realize you need a project and obviously have a lot of money burning a hole in your pocket, but if you don't have experience with power systems enough to know how an inverter works, you shouldn't be trying to use it in a way that is not intended. That's a good way to let smoke out of the controller or hurt yourself in the process. Also, if you don't have experience with Hydrogen Fuel cells, I suggest you get a small one to play with first. Hydrogen is no joking matter. In compressed cylinders it can be very dangerous. I realize there's hydrides that allow you to store hydrogen in crystals, but that requires compressed hydrogen too.... from another hydrogen tank, or from an at home hydrogen generator/compressor (not cheap). Another thing is that you need to convert the output to a useable voltage and may require a large DC-DC converter with controls associated with it (current and voltage control as well as an enable/disable). That's not to mention that you'd need to integrate to the Zero electrical system so that it can turn off charging once voltage gets too high (integrate into their BMS). All of this is an integrated system and unfortunately neither Zero nor Sevcon is likely to give you much in the way of schematics or sourcecode.

I'd spend the money on an extra battery and have them advice you on how to integrate that into your system. I know Terry has done that and it works very well and is way more cost effective.