A Modified FOPID Versus H¥ and m Synthesis Controllers: Robustness Study

Saeed Seyedtabaii

---

URL :   http://research.shahed.ac.ir/WSR/WebPages/Report/PaperView.aspx?PaperID=106292
Date :  2019/02/25
Publish in :    International Journal of Control, Automation and Systems

Link :  http://dx.doi.org/10.1007/s12555-018-0033-x
Keywords :Modified, Synthesis

Abstract :

---

The H¥, m synthesis and fractional order (FPM) controllers are types of robust designs that use the linearized model of the system and provide a linear controller. The m synthesis approach directly considers the uncertainty, but H¥ and FOPID run for the worst uncertainty scenario. mFPM is the modified version of FOPID design where 1) it takes into account the given uncertainty by a graphical Phase Margin Distribution Map (PMDP), and 2) reduces the controller design calculations by working on the samples of the system frequency response instead of its analytical equation. The design strategy can perfectly force the desired flatness in the phase margin band and maintain the system performance robustness. For evaluation, the algorithms are applied to a second-order uncertain system and a perturbed UAV roll control. In both cases, the lowest output response variance and the best performance robustness is gained from the mFPM design. This is verified through numerous simulations.