Magic Pie 4 regeneration not working

[Ron]

Hi,
I've got about 100km on my new vector mp4 and I'm loving it.  My problem is that the regenerative braking is not working.  I've got the programming cable and haven't figured out how to enable it.  My bike uses a 12s lipo pack so I set the controller for 48v.  I know the controller is seeing the brake inputs as the throttle gets cut when I press either brake.  The attachment is a .png with the latest controller parameters.


Tia.

[Bikemad]

Hi Ron,

It looks like your regen is already enabled so I'm puzzled as to why it doesn't work.

Did you reload the stored setting from the controller to make sure they had been saved correctly or is it possible that the 48V battery voltage setting might not have been saved?

Do you have any form of diode in your LiPo pack that would prevent the pack from receiving regenerative charge current?

Does it make any difference if you set the "EBS Peak Phase Current (A)" to 80%?

I notice that the software you are using shows "Maximum Reverse Speed (rpm)" instead of "Decel level 1 (rpm/s)" so it might be worth trying another version of the program to see if it makes any differerence.

Try setting it up with "LBMC_GUI_v3.1.2_GoldenMotor.exe" which is in the Dropbox folder and see if it makes any differerence.

I think the "Decel level 1 (rpm/s)" can be set up to a maximum of 380.

If it's still the same try the other one too "Revised GM_v3_1_1(201406231)_GED.exe".

When I used the wrong software on one of my controllers it would adjust and save the Acceleration setting in the controller but it made no difference to the motor's actual acceleration which remained the same on 20, 40, 60 80 and 100%.

It might be worth setting the acceleration level to 20% just to see if it changes. If it makes no difference to the motor's acceleration then you are probably using the wrong software.

Alan
 

[Ron]

Hi Alan,


Thanks for your reply.  This is what I have found so far:


- I did reload the parameters from the controller and they were correct, the bike is setup for 48v. 
- There is no diode on my battery pack.  The lipo's are naked without any BMS on them. 
- Setting "EBS Peak Phase Current (A)" to 80%  makes no difference. 
- I've used both of your parameter changing programs and one from GM Canada.  All three programs give the same no regen result.
- I was able to change my current from 25A to 30A and it did work.  I tried changing it back to 25A but regen was not effected. 
- I also tried loading default parameters with no change.
- The last thing I tried was manually deleting the parameter values and reentering them with no success.


Ron.
PS.  Setting the acceleration level to 20% is cruel :-) haha.

[Ron]

I've not seen any instructions on this kit and how it operates.  I assume that when I hit the ebrake the regen will engage.  The other way I've tried was to release the throttle when going downhill and neither way works for regen on my rig.
Ron

[Ron]

I did get a bit of regen yesterday.  I was going downhill at around 45 to 48 km/hr and when I twisted the throttle a little bit from the off position the regen engaged.  It seemed to engage more when I turned the throttle on.  If I turned the throttle too far then the bike would try to accelerate again (not that is would go faster than it was already).  According to the cycle analyst it was generating 600 watts which is great.  Is this normal?  Does anyone have any ideas on what I can try to get my regen working all the time? 

[Bikemad]

Hi Ron,

My regen operates every time the brake lever is pulled while travelling above ~8mph and cuts off automatically below ~4mph, but I have also noticed the momentary braking effect when you gradually open the throttle while free-wheeling at higher speeds.

I suspect that your lack of regen when applying the brakes is due to a problem within your controller itself, and I suggest that you contact your supplier and explain the problem and hopefully they can arrange for the controller to be exchanged for another one to cure the problem.



Alan
 

[Ron]

Hi Alan,


I've contacted Gary about the issue.  I do know that the brake lever activation's are getting seen by the controller as the motor power cuts off.  Hopefully a new controller is on the way.


Thanks for all your help!
Ron

[Ron]

I've replaced the original controller with a new one from GM Canada and it still doesn't work.  Could it be a hall sensor or something in the hub causing it?  I did verify the controller software parameters and they are correct.  This is strange .... Help!!

[Bikemad]

Hi Ron, it is unlikely to be anything to do with the motor because it probably would not run if a Hall Sensors has failed.

When you say "it still doesn't work" I presume you mean it's just the regenerative braking that still doesn't work and everything else is working as it should? (throttle OK, cruise OK and motor stops while braking etc.)

Was the new controller was set for 48V?

I discovered while testing my Smart Pie 4 on the 24V setting with an 8S LiPo pack (29.6V nominal, 33.6V fully charged) that regen would not work until the battery voltage had fallen below ~32V, which I presumed was meant to prevent it from overcharging a 24V battery.

In your case the battery voltage is lower, not higher, and I would expect your fully charged 12S LiPo pack (50.4V) to be well within the working voltage range of a typical 48V battery. 

Although your 12S LiPo pack is only 44.4V nominal (slightly less than 48V) it might be worth trying it on the 36V setting with the Over Voltage Protection Value set to ~52V to see if it makes any difference to the regen.

Alan
 

[Ron]

Hi Alan,


Yes, I mean everything works good except for regen braking.  The controller was set to 48v and the parameters you told me to change in your previous posts were done as well.  I tried setting the voltage to 36v and OVP to 52v and still no regen.  I'll have to discuss the next step with GM Canada unless you have any more ideas.  Thanks for all your posts the information and support you provide is awesome.


Ron

[Ron]

I've sent my MP4 wheel back to GM Canada to try and fix the lack of regeneration issue.  I'm at a loss as to what to try next.  Is there any possibility that my wiring harness or throttle could be causing any issues?  The only deviation from a standard install on my wiring is the cycle analyst shunt. Here is a video showing the testing GM Canada did to prove the regeneration is working (the first 78 seconds of the video can be skipped as it only shows the unboxing of the MP4). https://youtu.be/k5Wc8aWQ0n0?t=78

[Bikemad]

Hi Ron,

I was wondering whether the your regen problem was due to the 12S LiPo pack you were using so I carried out some tests today on my MP4.
I have a 1S pack, a 2S pack and a 3S pack in addition to my normal 4S hard case packs so I've been doing some testing today using a LiPo pack made up of between 8 to 13 5Ah cells:



Using 12 cells (to simulate your pack) and the default 48V setting the regen worked every time.

I also tested 8S, 9S, 10S, 11S and 13s and regen works with all of them if the voltage in the controller is set to ensure they are within the usable voltage range, so I still don't understand why your regen doesn't work.
The shunt for the Cycle Analyst should make no difference whatsoever to the regen.

I have also discovered that I can run my 8S pack on a modified 36V setting (instead of the modified 24V setting I had before) and with the "Undervoltage protection value" set at 27V it can still discharge the cells down to 3.375V each which is ideal for my use.



Unfortunately, the lowest voltage I could enter on the "Overvoltage protection value" was 48V but as I don't do much high speed braking normally on this bike it shouldn't really be a problem.
On the 36V setting the battery gauge also works much better on the Smart LCD Display:



On the 24V setting it always remained full even if the battery was half empty.

I also did some testing using a pair of wattmeters to measure the regen current and here are the result:

Maximum wattage was 892.8W under power and 567.4W generated during regen @ 21.87mph with ~31V battery voltage.
Maximum current was 29.98A under power and 17.92A produced during regen.

I tried the same test later when the battery voltage had dropped and the regen result was much higher:

Maximum wattage was 798.2W under power and 805.2W generated during regen @ 20.00mph with ~30V battery voltage.
Maximum current was 27.46A under power and 26.12A produced during regen (shown on the lower wattmeter):



Even at my relatively slow speeds of 20~22 mph the regen definitely produces a lot of power!

Alan
 

[Ron]

Wow, thanks for your in depth investigation of the different battery packs.  The shunt is just a large resistor and really can't make any difference as you have said.  I only mention it to let everyone know my mp4 configuration.  The next thing I'm going to try (once my wheel gets back to me from GM Canada next week) is to check the throttle and brakes and try to figure out if anything seems "wonky".  I'm not sure how this could effect regen but I'm grasping as straws.  Here is a list of things I'm going to look at, feel free to add any other suggestions.


1. Supply 5 volts to the throttle and measure the voltage coming from the throttle in full throttle and no throttle.  I think full throttle should be 4.25v.  Should no throttle be zero volts?
2. Disconnect the throttle connector and check regen going downhill.
3. Disconnect each brake connector individually and check regen.
4. Double check the un-terminated horn/light feeds to ensure isolation.
5. Disconnect the cruise connector and check regen.
6. kick the bike, curse a bit and check regen 


It really is a great unit even without regen but it would be perfect for me if regen worked.  Special thanks to Alan for all your help!


Ron

[Ron]

I finally got the regen issue fixed, it was a faulty brake lever.  See this thread for other problems caused by the errant brake lever. http://goldenmotor.com/SMF/index.php?topic=5639.0