How to tune the PID controller for Simscape Vehicle model ?

I am facing problem in tuning the PID controller for my simscape vehicle model. Below are the description about the model.

1.) Input is the vehicle speed setpoint from step block. I have used PI controller to convert the vehicle speed error to acceleration demand with limit 0 to 1.

2.) With a lookup table, I have converted acceleration demand to engine speed demand.

3.) Then I have used another PID controller to correct the engine speed error and limited it to 0 to 1, which is the input to the throttle.

I just need some guidance on finding out the appropriate gains for both of my controllers. I have also attached my model and .mat file for your reference. Please help me.

[Darshil Dharod]

Hi Arun,

I am also developing a hybrid drivetrain model in Simulink. Can you help with my following questions:

1) How do you get the engine rpm demand from the acceleration demand ? How do we get the engine rpm values for the corresponding acceleration demand value for the lookup table ?

2) I want to couple the torques from the electric motor and the ICE and deliver the summation of the 2 torques to the final driveline using a torque coupler ? Do you have any idea about how to model such a gear system ?

Any help would be much appreciated.

Thanks you in advance.

Answer 1

[Arvind Sathyanarayanan]

Have you tried the PID tuner app? You will to replace your controller with the MATLAB PID Controller to use the app. You could follow the example here.

Answer 2

[Arun Pandian Kumaresan]

Hello Mr.Sathyanarayanan,

First of all, thank you so much for your reply. I followed that example and tuned both the PI controllers in my simulink model and I have posted the simulation result below. When I replace step block with a traffic simulation software (SUMO) and run the model, the vehicle speed is always zero. I will post the simulatino result soon after this comment.

Answer 3

[Arun Pandian Kumaresan]

Answer 4

[Arun Pandian Kumaresan]

For the same controller gain values, the vehicle speed (blue colour) is in negative and when I use step block it is working fine. Please provide me some suggestions on how to proceed. Hope to get a reply from you.

(Yellow colour is the vehicle speed setpoint)

Answer 5

[Arun Pandian Kumaresan]

*For the same controller gain values, the vehicle speed (blue colour) is in negative when the input is from traffic simulation software, but when I use step block it is working fine. Please provide me some suggestions on how to proceed. Hope to get a reply from you.

[Arvind Sathyanarayanan]

Arun, it looks like you added a 20 kHz lowpass filter (20 kHz Lowpass filter 3) on your feedback which could be affecting the perfomance of your controller.

Have you tried running your model without this filter?