Buying dead vectrix for ressurection...
Hey all, brand new here, but I have been reading up on the vectrix with some interest - When these first came out, I thought that they were a great idea, but couldn't come at the price.
That said, I have managed to get hold of a vectrix with a dead MC card, and dead charger. And no batteries. It was very cheap though :)
I've come from an electrical engineering background, so none of this worries me excessivly - if the MC card is really toast, the hardware makes a great starting point for a home made controller - or at least a heavily modified EBike controller running some truly massive 200V MOSFETS - something like IRFP4668 TO-247 (130A each, probably 4 in parallel, each with individual drivers) - at $10 each, plasma events are not quite so costly. Only 24 to go into avalanche :) 0.008 Ohm on resistance... Nice.
If its only the IGBT block, then replacing this (or replacing it with a Mosfet bridge + drivers) is not a major issue.
The lack of current for immediate acceleration doesn't sound particularly impressive, but I'm sure this can be resolved :) Scale the current sensors output at lower speeds maybe.
I don't yet have it in my hot little hands, but its coming soon... In the meantime, does anyone have a lead on the service manual for one of these? The wiring diagrams and schematic would be very interesting to see.
Also, dead MC cards seem difficult to get your hands on in this country as well - anyone have any leads on these either?
Welcome!
That sounds most interesting, building a custom MC replacement.
What we have so far is the option to upgrade to Lithium including a different charger (Antiscab) and re-programming of the original charger software (The Laird) so that it treats the battery more gently.
There have not been many MC repairs described, yet. That makes it likely that even very simple faults will have been left unrepaired, like poor connection to the IGBTs causing smoldering. You might be lucky!
How easy or not it is to design a MC remains to be seen. Bear in mind that there is an encode disk at the rear wheel and that Canbus communication is required between that encoder and the MC board. That could be very tricky, to my knowledge no-one has so far succeeded in accessing and modifying the MC firmware.
Eyeinthesky had a MC board with failed IGBTs and ended up buying a used new board, maybe he still has the old one?
The gearbox is tough as nails as far as I know.
I know of someone who has been riding a Vectrix for years with just one planetary gear installed instead of all three.
My rather uneducated guess is that this would increase the loads on the remaining parts by a factor of at least three, but maybe much more. They are straight cut gears.
I've done some research on the encoder wheel, its pretty tricky BUT it still has hall sensor type outputs, so using these to drive a high powered controller with regen etc is not out of the question - even if they need to be advanced/retarded, this is possible to do in software.
yep, those hall sensors are for starting in square wave IIRC.
The stock MC switches to sine wave once the motor rpm is high enough
I think if I do go this way I may have to do some sensible current limiting because I'm not sure of the strength of the gearbox - will it lift the front wheel or shatter the gearbox if the motor gets hit with 150A+ off the line? My ebike hits 55A off the line and it will flip the bike (and rider) if caution is not exercised when moving off.
the stock MC gives 275A phase current.
On my bike, this peaks at 220A battery current.
The Gearbox uses (thick) single ratio gears, you will lose traction before this thing breaks.
Matt
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I have taken delivery of the bike, the MC card is toast, the IGBT contacts have gotten so hot that one has charred the board quite badly, and there is one terminal melted off completely. Yikes. Terrible design this part, really needs not to go through the board. ...
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That sounds very promising, I did repair similar damage to my Vectux MC, although much less severe by the sound of it.
But when I fixed one of the three phase posts which had burned a little bit, I checked all three by trans-illumination and I saw no internal layers. You can possibly grind the PCB material away until you reach the IGBT unit underneath it, then connect directly to that.
See this thread for details: http://visforvoltage.org/forum/3582-vectux-quotopen-source-vectrixquot
I know of someone who has been riding a Vectrix for years with just one planetary gear installed instead of all three.
Only one??
Mik, did he want to reduce the noise? Is the gearbox still ok?
I know of someone who has been riding a Vectrix for years with just one planetary gear installed instead of all three.
Only one??
Mik, did he want to reduce the noise? Is the gearbox still ok?
Yes, two of the three planetary gears were reportedly removed to reduce noise levels (successfully) and the Vectrix keeps running without (gearbox) problems, since several years.
Yes, two of the three planetary gears were reportedly removed to reduce noise levels (successfully) and the Vectrix keeps running without (gearbox) problems, since several years.
Very interesting... My gearbox is becoming noisier, and I've been unable to find single good solution... taking two gears out is risky, but may work...
The lithium conversion is definitly on my mind, the bike is coming with no batteries - Still undecided on the path I am taking, but the thundersky or sky energy look OK, but with some LiPoly Nanotechs in parallel to reduce the sag under load - There is some pretty serious stuff out there - a 5AH 40C (yes, 200A) should help keep the thunderskys happy and alive for longer.
I've done some research on the encoder wheel, its pretty tricky BUT it still has hall sensor type outputs, so using these to drive a high powered controller with regen etc is not out of the question - even if they need to be advanced/retarded, this is possible to do in software.
I think if I do go this way I may have to do some sensible current limiting because I'm not sure of the strength of the gearbox - will it lift the front wheel or shatter the gearbox if the motor gets hit with 150A+ off the line? My ebike hits 55A off the line and it will flip the bike (and rider) if caution is not exercised when moving off.
The existing MC board does lend itself well to redesign, the the signals that would drive the IGBT's (via the inbuilt drivers in the block) could also quite easily drive mosfet drivers as well - there is a lot of similarity between the two, IGBT's have a 'Tail' they don't shut off as quickly as mosfets, but they have a much better SOAR (safe operating area region) than mosfets - You can basically drive them to their voltage and current limits concurrently. Do the same with a mosfet and it will die. Conversely, mosfets run much cooler, you just need more of them to make up for the poor SOAR curve. Add lots of low ESR capacitance as well, and you have a fairly robust full bridge.
The current sensors themselves may be moved off the board as well, I think some fun may be had with launch currents if these are fooled into producing a lower voltage than they actually are for the MC board.
Another spare dead board would be good, because its pretty likely I'll toast one :) Hopefully eyeinthesky didn't throw it out...