Bafang ultra upgrade to 2500watt

jpc6000

100 W
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Hi,

I building fast E-bikes that can drive 45mp/h and homologate it as a motorcycle.

Therefore I use the Bafang ultra drive motor g510.

The problem is that the controller only give 1000 watt, with the ludicrous controller 2500watt. But I can't find it. Luna don't sell it, and don't give info.

I don't know of the controller is only hacked or that's a other controller?

I will try to hacked it also, or I can use the external E.R.T. 12 MOSFET 3000W Sinewave Controller, the heat of the controller is so out of the motor and better I think.

Anybody suggestions?
 
see there the controller pcba inside the G510. You need to change the R value of the two resistors acting as a shunt if you want to get the amps above 30A.

This is what Luna is doing on their 2.5kW controller (and nothing else contrary to what they claim).

I believe this motor is perfectly able to take 3kW, I just did a quick comparion with the bbs02 750W. The G510 is just overkill. Heaps of cooper in there.

The stock mosfets specs are unkown but they can be easily replaced as they come in a pretty bog standard D2-PAK smd package.

 
Hi,

Thanks, great info.

Do you also know much the resistor may be?

Luna have doubled it. When programme the controller on 25A he gives 50A that is what I want.

Mine battery pack gives max 52A at 63V, 4p15S can the g510 work with 63V?

The bbs02 max 61,5V.

Regards :pancake:
 
for the R value, just enlarge the pic of the pcba I did (click on it to get the hi-res version), you can read it. Both are 5 mOhms

The main filter caps as you can see is 63V max, so it is borderline with your setup. However I believe there is enough space to fit higher V-rated caps in the casing.
 
The reason you can't get those from Luna is too many of them failed at that power level. It might work if you made the main caps bigger.

You would probably be better off going with an external controller.
 
fechter said:
The reason you can't get those from Luna is too many of them failed at that power level. It might work if you made the main caps bigger.

You would probably be better off going with an external controller.

do you have more insight to these failures ? I.E was it mostly mechanical or controller ? The motor core is perfectly sized for ~3 kW, but I'm not sure the reduction gearing can handle that much...

If the failures were electrical however this is kinda a good news because the power pcba can quite easily modded with lower Rds(on) fets + higher voltage caps.

Also their thermal interface with the casing can be greatly improved with some good thermal paste on the backplace (don't have any from the factory).

For an extreme amp setup I would mill the casing exterior behind the fets and glue w/ thermal epoxy a custom heatsink on the outside.
 
As far as I know, most of the failures were in the controller. I haven't heard of any mechanical issues. It would be easy enough to use an external controller but would need to be mounted somewhere. The main caps look pretty small to me, so I would guess that is the main reason for the failures. There really isn't much room inside for more/bigger caps. Maybe just better caps with lower ESR would work. Mounting extra caps outside the motor on the main power wires would be another option.
 
I have ask to Electric Race Technologies of the E.R.T. 12 MOSFET 3000W Sinewave Controller work with the Bafang ultra drive

I don't have received info.

does this work?

The controller produce a lot of heat, so this is better I think.

Also the mosfets are better.
 
I tried to locate spare parts for the ultra and none are available.

Tried GBK, BTN-Ebike, Luna and Frey (which sold me the motor). They asked bafang directly and they basically all came back with the same "Bafang does not supply parts for this drive"

The problem seems to be the same with all their other integrated mid drives (eg. the 2016 Max).

This sucks. Makes me more reluctant to run 2.5kW in the ultra now.
 
Hi,

This is indeed true, motor and spare sparts nowhere to find.

At my supplier I can buy it, soon I shall open mine e-bike shop and shall sell them worldwide.

If you need now something let me know, and shall inform about the price.

I am still waiting for the question about the external controller for the Bafang ultra. :?:
Mine electronic knowledge is hobby.

The answer that I got from Bafang:
bafang repiled us they never do big current controller for their products

but they admit that some clients modify the controller by themselves. :p
 
That's a very good news If you have access to the parts. Sent you a PM.

Lots of Ultra owners, and before that Max drives, will need them once they run out of warranty or do mods like use.


For the external controller it is surely doable. If you run sensorless you only need to connect to the motor phases.

If you want to run in sensored mode with the halls, you should now that bafang changed their sensor system.

In motors versions before V1.5, bafang used the classic 3 hall sensor arrangement, like on their BBS-XX series motor.

On V1.5 (the current one), they use a single IC hall sensor that reads a magnet on the tip of the rotor shaft. They must have done some wizardry in the Firmware to run with such setup as It must be much more prone to errors ??

However, the 3 hall sensor board is still in the motor but not connected. I believe they have leftover stock and at some point we will not find this board anymore, so this might be a problem if you want to run sensored because then you'll have to either supply the old 3-hall pcba or adapt the external controller to the single IC...





I wonder, a Grin phaserunner + CA3 might be able to do all that and keep the torque sensor of the Ultra ? That'd be sweet
 
This controller looks promising - https://endless-sphere.com/forums/viewtopic.php?p=1402253#p1402253
 
The std external bafang controller is too weak for the hills around here. It grinds to a halt pretty quick and heats up quick. Its limited to 20 amps @36v. I'm thinking of buying a spare, upgrading the mosfets and doing a shunt mod. I'm guessing (haven't opened one up yet) it's a 6fet, so I might be able to get 30amps through it with good fets. If anyone has done an upgrade on these bafang controllers I'd love to hear about it...
Cheers
 
I bought the phaserunner from grin technologies

for the controller to be programmed I need some parameters

https://fasterbikes.eu/en/index.php?controller=attachment&id_attachment=57

Motor Autotune

the motor’s kV:

Bafang motor ultra at 63V nominal 55V nT(Rpm) 185
185 rpm 55V, then a reasonable guess for the kV is
185/55 = 3.4 RPM/V

Correct?

pole pairs:

The effective pole pairs is a count of how many electrical cycles corresponds to
one mechanical revolution of the motor, and the Phaserunner needs this
information to correlate it’s electrical output frequency with the wheel speed. In a
direct drive (DD) motor, it is the number of magnet pairs in the rotor, while in a
geared motor you need to multiply the magnet pairs by the gear ratio.


How many pole pairs has the Bafang Ultra drive?

:wink:
 
jpc6000 said:
Bafang motor ultra at 63V nominal 55V nT(Rpm) 185
185 rpm 55V, then a reasonable guess for the kV is
185/55 = 3.4 RPM/V


How many pole pairs has the Bafang Ultra drive?

Try 55RPM/V
4 Polepairs

phasset.jpg

bafphas.jpg
 
Try 55RPM/V
4 Polepairs
does the engine work well with your parameters?

I think this is not true
manual says
The start of the autotune process asks for your best guess of the motor’s kV in
RPM/V, as well as the number of pole pairs in the motor. The firmware uses
these initial parameters for determining the test current frequency and you should
input values that are close to the expected ones. For example, if you have a
motor with a label that says 220 rpm 24V, then a reasonable guess for the kV is
220/24 = 9.1 RPM/V


spec bafang ultra.png

nT(Rpm) at 60V = 185
185rpm / 55V = 3,4V RPM/V

Polepairs

Yes 4 polepairs

The effective pole pairs is a count of how many electrical cycles corresponds to
one mechanical revolution of the motor, and the Phaserunner needs this
information to correlate it’s electrical output frequency with the wheel speed. In a
direct drive (DD) motor, it is the number of magnet pairs in the rotor, while in a
geared motor you need to multiply the magnet pairs by the gear ratio


The bafang ultra is a geared motor, not?
multiply the magnet pairs by the gear ratio!

I do not think that the gear ratio is 1
 
jpc6000 said:
I do not think that the gear ratio is 1

Here is a post from another thread regarding the BBSHD + Phaserunner:

I have got some basic info from Justin directly:
there are two ways of tuning the PR to a mid drive like the BBSHD system. Either you look at the total pole pair and gear ratio from the motor to the crank, and run autotune in reference to the crank RPM. Or you do it in reference to the motor itself and do everything in terms of the motor RPM.
From what I remember the BBSHD motor has 8 magnets, so 4 pole pairs, and then has a ~22:1 gear ratio to the cranks, with an effective crank RPM/V of 3.5
So you can use 88 pole pairs and initial KV guess of 3.5, or you can use 4 pole pairs with initial KV guess of 77 rpm/V or so. Either way will work fine.


The Ultra has a gear ratio of 18,26

So you could also do (with a 52V battery):

73 Polepairs
3RPM/V

Or as I said:

4 Polepairs
55RPM/V

I'm not an expert but personally I don't think the exact number is very important.
I tried many settings and if the numbers are too far off, autotune just gives you a failure.
Change the numbers and try again!
 
Now I understand, thanks.

I have also youtube link Bafang ultra
https://www.youtube.com/watch?v=1lki_sGQfJ0&feature=youtu.be&t=2m12s

:D
 
This should be very nice, if I can use the torque sensor.

I need to halve the voltage from the cycle analyst.

With a component or electronic board? :roll:
 
jpc6000 said:
I need to halve the voltage from the cycle analyst.

With a component or electronic board? :roll:

You could get a component but there are some 5V tabs in the cycle analyst that you could use.

CA_Pad_Layout.gif


The phaserunner also has a 5V cable (on the unused throttle cable)

Where will you place the Phaserunner?
Inside the Ultra?
 
Field Weakening for Speed Boost

One useful feature of the Phaserunner as a field oriented controller is the ability
to boost the top speed of your motor beyond what is normally possible from your
battery voltage. This is done through the injection of field weakening current that
is perpendicular to the torque producing current

max field weakening current ? amp :?:

The exact speed increase for a given field weakening current will depend on the
characteristics of your particular motor, and increasing the speed this way is less
efficient than using a higher voltage pack or a faster motor winding. But for a
speed boost of 15-20%, the additional losses are quite reasonable considering
the gains.

Do any know how much ampere is optimal for this motor, at 63V and 50Amp
Battery can give 52Amp max
 
The phasecontroller
I also want to cool the phaserunner, for that I use the frame, alu and tita are good heat conductors. But there must be good contact between the phaserunner and the frame. That is why I would remove the paint from the frame. And then use a good heat conductor between the phaserunner and the frame. Heat fransfer pasta that they use for computer processor seems to me an idea. Maybe it washes away through water, so this has to be tested. Perhaps a copper plate can be used first, which ensures that the paste does not wash away. The notches with 6 deeper nuts are the heat source and filling them with pasta is better. The frame is the best cooling source.
20180907_101912 (Groot).jpg
Removing the Bafang controllerboards, (bad work bafang already affected by acid)
View attachment 3
View attachment 2

20180907_110307 (Groot).jpg

How can I fill this cap from the old cables :?:
 

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