I suggest you to take a look to one of my papers called robust controllers tuning ....

You can also see the paper of d'arco called automatic tuning ...

If you are interested to other methods for controlling inner loops, then we can discuss furthermore.

Taoufik.

Dear Diogo Marujo

Please see these attachments links

Best regards

Article Designing robust controller to improve current-sharing for p...

Article Small-Signal Stability Analysis of an Inverter-Based Microgr...

https://www.mdpi.com/1996-1073/13/13/3480/pdf

Thanks for sharing.

Continuing the discussion, is there any technique that does not use state-space representation?

If your are using any one optimization technique to PI controller in order to select gain values under various disturbance it will give better response compare to normal tuning methods.

Thanks for the reply Ramesh Jayaraman . Considering the use of optimization techniques, what would be the necessary approach to reduce the simulation time? Evolutionary approaches like GA and PSO require that many simulations be performed. For example, the Matlab simulation of a Microgrid with several converters requires great computational effort to perform these simulations.

Simulation efforts are required using whatever optimization method but to reduce time and effort try using the similarity of converters in parallel that may reduce the the Kp and Ki may be by assuming all converters equivalent to one Try this adIa. If possible

Following!!!

Dear Diogo , The following documents and links give details

Article

Robust PI controller design for frequency stabilisation in a hybrid microgrid system considering parameter uncertainties and communication time delay

• IET Generation, Transmission & Distribution ( Volume: 13 , Issue: 14 , 7 23 2019 )
• DOI: 10.1049/iet-gtd.2018.5240
• Arockya Jaya Samy Jeya Veronica ; Natarajan Senthil Kumar ; Francisco Gonzalez-Longatt