کنفرانس بین المللی کنترل ، ابزار دقیق و اتوماسیون

صفحه اصلی / نهمین کنفرانس بین المللی کنترل ، ابزار دقیق و اتوماسیون

Robust State-Feedback Local Voltage Control for Islanded Uncertain DC Microgrids Using LPV Modeling

نویسندگان :

Mohammad Reza Asadi¹ Mohammad Hossein Kazemi²

1- دانشگاه شاهد 2- دانشگاه شاهد

کلمات کلیدی :

DC microgrid،linear parameter varying،decentralized control،linear matrix inequality،robust stability،robust performance

چکیده :

This paper proposes a decentralized robust local voltage control scheme for islanded DC microgrids (MGs) in order to achieve robust stability and robust performance. The studied microgrid consists of distributed generation (DG) units with a general topology, which are modeled with a linear parameter varying (LPV) structure, and each of them is assumed to have a local uncertain ZIP (constant impedance (Z), constant current (I), and constant power (P)) load. One of the main advantages of the proposed controller is the scalability of the design method and the full decentralized structure of internal voltage control. The proposed controller not only guarantees the stability and performance of the nominal closed-loop microgrid but also maintains the robust stability and robust performance of the microgrid under different sources of uncertainties which can modeled by the LPV modeling approach. Every local voltage controller is obtained by solving a unique convex optimization problem, which leads to the robust stability and desired performance under various disturbances. First, a perturbed LPV state space model is considered for each distributed generation subsystem and various uncertainties are modeled at the vertices of a polytope. Then, all the control objectives lead to a robust dynamic state-feedback-based controller for a linear time invariant (LTI) polytopic system with H_∞ performance and pole placement criterion. Finally, the obtained non-convex problem is reduced to a linear matrix inequality (LMI) optimization problem and the local robust voltage controller is derived for each DGs. Several simulation case studies are performed in MATLAB to demonstrate the effectiveness of the proposed controller.