A generalized descriptor-system robust H∞ control of autonomous microgrids to improve small and large signal stability considering communication delays and load nonlinearities. (November 2017)

• Record Type: Journal Article
• Authors: Baghaee, Hamid Reza; Mirsalim, Mojtaba; Gharehpetian, Gevork B.; Talebi, Heidar Ali
• Is Part Of: International journal of electrical power & energy systems. Volume 92(2017)
• Page Start: 63
• Page End: 82
• Publication Date: 2017-11
• Subjects: Microgrid -- Descriptor-system robust H∞ control -- Distributed energy resources -- Linear matrix inequality -- Time-delay systems -- Iterative algorithm -- Stability; Electrical engineering -- Periodicals; Electric power systems -- Periodicals; Électrotechnique -- Périodiques; Réseaux électriques (Énergie) -- Périodiques; Electric power systems; Electrical engineering; Periodicals; 621.3
• DOI: 10.1016/j.ijepes.2017.04.007
• Languages: English
• ISSNs: 0142-0615

Abstract

Highlights: Descriptor system approach to enhance performance of H∞ controller and DRSM scheme. Set point tracking, disturbance rejection and improving performance of microgrid for small/large-signal disturbances and nonlinear loads. The theoretical concepts, mathematical modeling of microgrid, basic theorems, and design procedure. A set of linear/bilinear matrix inequalities that is solved using a new iterative algorithm as convex optimization problem. Offline time-domain simulation and experimental verified by OPAL-RT real time digital simulator. Abstract: This paper presents a descriptor system H∞ approach to enhance performance of robust H∞ controller and previously-reported decentralized robust servo-mechanism (DRSM) control scheme for autonomous voltage sourced converter (VSC)-based microgrids including multiple distributed energy resources (DERs). The power management system specifies voltage set points for local controllers and the frequency of each DER unit is specified by a hierarchical droop-based control structure. A descriptor system H∞ robust controller is designed based on a closed-loop representation of microgrid either with H∞ or DRSM controller for set point tracking, disturbance rejection and improving performance of microgrid for small/large-signal disturbances and nonlinear loads. Here, unlike some of the previous researches, the load current is modeled as disturbance and also communication time-delay is considered. The theoretical concepts of proposed control strategy, including mathematical modeling of microgrid, basic theorems, and design procedure are outlines. Then, design problem is formulated by a set of linear/bilinear matrix inequalities and then solved using a new iterative algorithm in the form of convex optimization problem. To demonstrate effectiveness of the proposed control scheme, offline time-domain simulation studies are performed on a multi-DER microgrid in MATLAB/Simulink environment and also the results are experimentally verified by OPAL-RT real time digital simulator.