Reduced-Order Small-Signal Model of Microgrid Systems


The objective of this study was to develop a reduced-order small-signal model of a microgrid system capable of operating in both the grid-tied and the islanded conditions. The nonlinear equations of the proposed system were derived in the dq reference frame and then linearized around stable operating points to construct a small-signal model. The high-order state matrix was then reduced using the singular perturbation technique. The dynamic equations were divided into two groups based on the small-signal model parameters ε. The slow states, which dominated the systems dynamics, were preserved, whereas the fast states were eliminated. Step responses of the model were compared to the experimental results from a hardware test to assess their accuracy and similarity to the full-order system. The proposed reduced-order model was applied to a modified IEEE-37 bus grid-tied microgrid system to evaluate systems dynamic response in grid-tied mode, islanded mode, and transition from grid-tied to islanded mode.


Electrical and Computer Engineering


National Science Foundation (U.S.)


This work was supported in part by the National Science Foundation under awards 0812121 and 1406156.

Keywords and Phrases

Dynamic Response; Electric Power Distribution; Nonlinear Equations; Perturbation Techniques; Dynamic Equations; Full Order System; Grid-Tied Microgrid; Micro-Grid Systems; Operating Points; Reduced Order Models; Singular Perturbation Technique; Small Signal Model; Heterojunction Bipolar Transistors; Islanded Microgrid; Microgrid Modeling; Model Order Reduction; Singular Perturbation

International Standard Serial Number (ISSN)

1949-3029; 1949-3037

Document Type

Article - Journal

Document Version


File Type





© 2015 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Oct 2015