zombiess
10 MW
*Take this post with caution as I have not actually measured the phase current out of the controller, but the way the controller is behaving I strongly believe it is limiting phase amps*
As some of you have seen I have posted about issues I have had with some EB324 controllers. Xie Chang's new style 24 FET controller. What does that have to do with the title of this post? Well I decided to stress the snot out of one that I made a repair on to see if it would blow up. So far I only have 7 very hard miles on it.
On to the testing and the discovery.
First a little background. EB324 controllers can not be programmed as a 24 FET controller since the software that supports them only goes up to a 18 FET controller. Stock the 12 FET controller uses 2 shunts, 18 FET controller uses 3 shunts and the 24 FET controller uses 4 shunts. The few EB324 controllers I have built only have 4 shunts installed into them because I was unsure how changing the shunt effected amp settings.
Since I first got my hands on an EB324 controller about 2 years ago I have strongly suspected that the controller actually limits phase current through some algorithm or measurement scheme that is very different from the EB2XX controllers. I have suspected this because lowering the shunt appears to have no effect on the phase current setting, only the battery current. I have also noticed that the EB2XX controllers are a lot more punchy compared to EB3XX controllers.
The test setup:
Greyborg Warp Frame with Cromotor V2 in 19" wheels with 25.3" tires
18S3P 15AH battery pack, 75V fully charged
CA V3 in pass thru mode with wattage limit set to 20KW and current set to 200A and ramp rates at 10V/s
EB324 IRFB4115 controller programmed as an EB318, block time 0.0s, shunt value of 0.83mOhm, controller expects 1.00mOhm
Multiple dead stop to WOT passes made on each setting to get the highest peak possible.
Test 1:
Set battery amps to 30A in the software, this will allow ~52A to be pulled from the battery.
Phase current programmed to 105A in the software
Test ride CA showed a peak current of ~54A
Test 2:
Set battery amps to 49A in the software, this will allow ~85A to be pulled from the battery.
Phase current programmed to 105A in the software
Test ride CA showed a peak current of ~89A
Test 3:
Set battery amps to 100A in the software, this will allow ~175A to be pulled from the battery.
Phase current programmed to 105A in the software
Test ride CA showed a peak current of ~102A <--- Ah HAH! What's going on here?
This is where I started to scratch my head since I was expecting the peak to overshoot by quite a bit before settling down as the EB2xx controllers would do. I made several pulls just to be sure. Went back and checked my laptop and the settings were just as I have posted.
Test 4:
Set battery amps to 100A in the software, this will allow ~175A to be pulled from the battery.
Phase current programmed to 120A in the software
Test ride CA showed a peak current of ~118A... looks like the battery current is following phase current, as it should.
Test 5:
Set battery amps to 100A in the software, this will allow ~175A to be pulled from the battery.
Phase current programmed to 150A in the software
Test ride CA showed a peak current of ~149A... yup, battery current is following phase current.
Test 6:
Set battery amps to 100A in the software, this will allow ~175A to be pulled from the battery.
Phase current programmed to 175A in the software, Figured why not, I have plenty more of these controllers I'm afraid to sell until I prove reliability
Test ride CA showed a peak current of ~175A... battery current is following phase current.
Test 7:
Set battery amps to 49A in the software, this will allow ~85A to be pulled from the battery.
Phase current programmed to 175A in the software
Test ride CA showed a peak current of ~85A... battery current is now limited by battery current setting x1.73.
So there you have it, the EB3XX controllers appear to limit phase current regardless of what the shunt value is and I suspect it does this at all throttle positions. There is very little if any overshoot noticed, at least on the CA V3. To really detect current overshoot I would need to hook up some current sensors and use at high speed capture loop to record the maximum. A device I eventually plan to make.
So if your settings are as follows (battery amps is actual amps, not just the programmed value) Battery amps are effected by the shunt
If Phase Amps > Battery Amps then Battery Amps = Amp limit
If Phase Amps < Battery Amps then Phase Amps = Amp limit
Wish I had someone shooting a video of the 175/175A ride. It's just enough power (I saw 11KW on the CA) to do a smooth slow rising wheelie if you yank up on the handle bars when giving it throttle. I managed to ride out a few power wheelies like this from really low speed with the longest one being about 25 feet with the front end hanging about 2' off the ground before it settled down.
End result of the ride, motor was warm to the touch, warm enough after sitting for a minute that I decided it was best to take it on a nice low speed ride to help cool it off vs let it sit and bake. In all I probably did somewhere around 40 dead stop/slow WOT pulls to 10-35mph with many being back to back. Controller case was slightly warm, outside temp was about 60F.
Other good news is this controller is taking some hard abuse. I did not it expect it to live at these levels. Only time will tell if it is going to work OK. This is the second controller I have repaired and installed on this bike. The first one kept blowing up the same FET (I gave up on it after 7 repairs ) on the high side of phase B. They are both returns from a customer who had issues with them. I hope they work so I may finish up the rest of these controllers I have.
As some of you have seen I have posted about issues I have had with some EB324 controllers. Xie Chang's new style 24 FET controller. What does that have to do with the title of this post? Well I decided to stress the snot out of one that I made a repair on to see if it would blow up. So far I only have 7 very hard miles on it.
On to the testing and the discovery.
First a little background. EB324 controllers can not be programmed as a 24 FET controller since the software that supports them only goes up to a 18 FET controller. Stock the 12 FET controller uses 2 shunts, 18 FET controller uses 3 shunts and the 24 FET controller uses 4 shunts. The few EB324 controllers I have built only have 4 shunts installed into them because I was unsure how changing the shunt effected amp settings.
Since I first got my hands on an EB324 controller about 2 years ago I have strongly suspected that the controller actually limits phase current through some algorithm or measurement scheme that is very different from the EB2XX controllers. I have suspected this because lowering the shunt appears to have no effect on the phase current setting, only the battery current. I have also noticed that the EB2XX controllers are a lot more punchy compared to EB3XX controllers.
The test setup:
Greyborg Warp Frame with Cromotor V2 in 19" wheels with 25.3" tires
18S3P 15AH battery pack, 75V fully charged
CA V3 in pass thru mode with wattage limit set to 20KW and current set to 200A and ramp rates at 10V/s
EB324 IRFB4115 controller programmed as an EB318, block time 0.0s, shunt value of 0.83mOhm, controller expects 1.00mOhm
Multiple dead stop to WOT passes made on each setting to get the highest peak possible.
Test 1:
Set battery amps to 30A in the software, this will allow ~52A to be pulled from the battery.
Phase current programmed to 105A in the software
Test ride CA showed a peak current of ~54A
Test 2:
Set battery amps to 49A in the software, this will allow ~85A to be pulled from the battery.
Phase current programmed to 105A in the software
Test ride CA showed a peak current of ~89A
Test 3:
Set battery amps to 100A in the software, this will allow ~175A to be pulled from the battery.
Phase current programmed to 105A in the software
Test ride CA showed a peak current of ~102A <--- Ah HAH! What's going on here?
This is where I started to scratch my head since I was expecting the peak to overshoot by quite a bit before settling down as the EB2xx controllers would do. I made several pulls just to be sure. Went back and checked my laptop and the settings were just as I have posted.
Test 4:
Set battery amps to 100A in the software, this will allow ~175A to be pulled from the battery.
Phase current programmed to 120A in the software
Test ride CA showed a peak current of ~118A... looks like the battery current is following phase current, as it should.
Test 5:
Set battery amps to 100A in the software, this will allow ~175A to be pulled from the battery.
Phase current programmed to 150A in the software
Test ride CA showed a peak current of ~149A... yup, battery current is following phase current.
Test 6:
Set battery amps to 100A in the software, this will allow ~175A to be pulled from the battery.
Phase current programmed to 175A in the software, Figured why not, I have plenty more of these controllers I'm afraid to sell until I prove reliability
Test ride CA showed a peak current of ~175A... battery current is following phase current.
Test 7:
Set battery amps to 49A in the software, this will allow ~85A to be pulled from the battery.
Phase current programmed to 175A in the software
Test ride CA showed a peak current of ~85A... battery current is now limited by battery current setting x1.73.
So there you have it, the EB3XX controllers appear to limit phase current regardless of what the shunt value is and I suspect it does this at all throttle positions. There is very little if any overshoot noticed, at least on the CA V3. To really detect current overshoot I would need to hook up some current sensors and use at high speed capture loop to record the maximum. A device I eventually plan to make.
So if your settings are as follows (battery amps is actual amps, not just the programmed value) Battery amps are effected by the shunt
If Phase Amps > Battery Amps then Battery Amps = Amp limit
If Phase Amps < Battery Amps then Phase Amps = Amp limit
Wish I had someone shooting a video of the 175/175A ride. It's just enough power (I saw 11KW on the CA) to do a smooth slow rising wheelie if you yank up on the handle bars when giving it throttle. I managed to ride out a few power wheelies like this from really low speed with the longest one being about 25 feet with the front end hanging about 2' off the ground before it settled down.
End result of the ride, motor was warm to the touch, warm enough after sitting for a minute that I decided it was best to take it on a nice low speed ride to help cool it off vs let it sit and bake. In all I probably did somewhere around 40 dead stop/slow WOT pulls to 10-35mph with many being back to back. Controller case was slightly warm, outside temp was about 60F.
Other good news is this controller is taking some hard abuse. I did not it expect it to live at these levels. Only time will tell if it is going to work OK. This is the second controller I have repaired and installed on this bike. The first one kept blowing up the same FET (I gave up on it after 7 repairs ) on the high side of phase B. They are both returns from a customer who had issues with them. I hope they work so I may finish up the rest of these controllers I have.