# Problem using Sevcon Gen4



## danibasket (May 9, 2018)

I am working in the design of an off-road motorcycle, using a Sevcon Gen4 controller in combination with a ME0913 motor.

My problem is that the driver disconnects itself when I jump with the motorcycle and the wheel is not in contact with the floor. I have checked all config parameters of Sevcon Gen4 as maximum torque variation per second, or maximum current limit, etc... 

I connected a CAN datalogger in order to save the error that the driver is producing and the can message is attached to this message. The error message means DSP OVERCURRENT FAULT, so I guess it could be an error regarding to the robustness of the current control system.

Any experience with similar problem or any idea to solve it?

Thanks,


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## cmcnall (Aug 12, 2015)

Do you have access to an IXXAT CanOpen Dongle and the DVT software?
It would be worth putting the bike up on a stand and checking encoder direction relative to wheel direction. I found mine were inverted and it was giving me the same error as you. In general it will make it easier to debug.

Also add your location to your profile so we know where you are. There may be someone local to you.


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## danibasket (May 9, 2018)

> Do you have access to an IXXAT CanOpen Dongle and the DVT software?


Yes, I have it and I have checked that all the parameters have logical values



> It would be worth putting the bike up on a stand and checking encoder direction relative to wheel direction. I found mine were inverted and it was giving me the same error as you. In general it will make it easier to debug.


I think that it is not problem of the encoder direction because I have normally performance in flat surfaces but when I try to jump with the motorcycle and I try to use the throttle with the wheeel in the air, the driver shuts down. But when I receive the new BMS, I will try to check the direction of the encoder.



> Also add your location to your profile so we know where you are. There may be someone local to you.


 I am from Europe man. I think that most of you are from the States, but I hope I find someone also from Europe. 

Thanks for your help Cmcnall. This problem is driving me crazy for last months.


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## frodus (Apr 12, 2008)

So what do you mean the driver disconnects. The motor controller=driver? the contactor=driver? can you elaborate?

Also, it seems you might be using a file that isn't tuned right. When the motor has no load, it may have issues in the file with the PID settings, so the control loop overshoots too much and goes into current limit.

Where did the controller and the DCF file come from? Have you spoken to them about the issue? 

Was this a kit?


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## sanfox (Mar 26, 2015)

Frodus try to decrease acceleration per second in motor parameters.
Also try to write and check log from controller during the jumping. I think the reason of error caused with mistakes in close loop controlling algorithm inside the controller.


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## frodus (Apr 12, 2008)

Can you please answer my questions:
*So what do you mean the driver disconnects. The motor controller=driver? the contactor=driver? can you elaborate?*

*Where did the controller and the DCF file come from? Have you spoken to them about the issue?* 

*Was this a kit?*


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## danibasket (May 9, 2018)

Sorry for my late respose Frodus, but I was not at home until yesterday.



> So what do you mean the driver disconnects. The motor controller=driver? the contactor=driver? can you elaborate?


Seems that the motor controller (Sevcon Gen4) is restarting or blocks performance of the motor for approximately 30 secs until you can run again. When this happens, you don't have to turn off/on your system. You only has to wait. When this occurs, the DSP OVERCURRENT FAULT message appears.




> Also, it seems you might be using a file that isn't tuned right. When the motor has no load, it may have issues in the file with the PID settings, so the control loop overshoots too much and goes into current limit.


It could be that the control system has not been tested or fitted for a motocross off-road motorcycle. But could I fit parameters by myself. How could I tune control parameters of the system? I don't even know which is the architecture or the control strategy implemented in the controller. Is there any automated way to do it?




> Where did the controller and the DCF file come from? Have you spoken to them about the issue?


I bought the controller to an official Sevcon supplier and they gave me the DCF for the Motenergy ME1115 motor. When I asked them, they said that it is the first time they have seen that error and have no idea about what could be the problem.



> Was this a kit?


It is not from a kit. Controller and motor bought separately.


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## danibasket (May 9, 2018)

> Frodus try to decrease acceleration per second in motor parameters.
> Also try to write and check log from controller during the jumping. I think the reason of error caused with mistakes in close loop controlling algorithm inside the controller.


It is not due to the acceleration per second max value because in flat surfaces (without jumping) I could run with the throttle at maximum without DSP OVERCURRENT FAULT error. It seems that it is related with the closed loop, but how could I adjust that parameters to prevent that particular case?


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## frodus (Apr 12, 2008)

turn down Kp? the proportional gain, so it doesn't overshoot. Also, turn down max current.


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## Hellectric (Apr 22, 2021)

Hi Danibasket

Did you solve this problem?


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