How to tune a PID Controller for a plant with two integrators?

I am designing a simulation of attitude control of a satellite using Simulink. I'm using a PID controller to control the actuation and I intend to stabilize the attitude (orientation). The output of the PID is the required actuation (torque), and the plant is used to estimate the net orientation as a result of the torque.

When I try to tune the PID controller using the Autotune feature of the Simulink PID Controller Block, I get an error saying, 'PID controller could not find an initial stabilizing controller using plant "Plant" '. One possibility is that my plant has two integrators as a result of which it may not be able to linearize the plant.

Answer 1

[Robert U]

Hi Aneesh Rao,

PID controller tuning is a field many people worked on already. Have a look here for references:

• https://en.wikipedia.org/wiki/PID_controller#Loop_tuning
• https://de.mathworks.com/help/slcontrol/gs/automated-tuning-of-simulink-pid-controller-block.html
• https://de.mathworks.com/help/slcontrol/automatic-pid-tuning.html
• http://faculty.mercer.edu/jenkins_he/documents/TuningforPIDControllers.pdf
• https://scholar.google.de/scholar?q=PID+controller+tuning&hl=de&as_sdt=0&as_vis=1&oi=scholart

If you would like to receive a more specific answer, you would have to share more information about your system to control.

Kind regards,

Robert