TY - JOUR
T1 - Impact of DG connection topology on the stability of inverter-based kicrogrids
AU - Song, Yue
AU - Hill, David J.
AU - Liu, Tao
N1 - Funding Information:
Manuscript received December 11, 2018; revised March 8, 2019; accepted April 21, 2019. Date of publication May 17, 2019; date of current version August 22, 2019. This work was supported in part by the Research Grants Council of the Hong Kong Special Administrative Region under the General Research Fund (GRF) through Project 17207918 and in part by the Theme-based Research Scheme (TRS) through Project T23-701/14-N. Paper no. PESL-00280-2018. (Corresponding author: Yue Song.) Y. Song and T. Liu are with the Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong (e-mail: [email protected]; [email protected]).
Publisher Copyright:
© 2019 IEEE.
PY - 2019
Y1 - 2019
N2 - In this letter, we theoretically explain that the common connection topology for inverter-based distributed generators (DGs) is harmful to the small-disturbance stability of microgrids. We first prove that the algebraic connectivity of a graph will approach zero in case of inappropriate expansion of nodes and lines. Such type of expansion is often the case in microgrids where new DGs are simply connected to the nearby nodes via single lines that leads to a tree-like structure. Furthermore, we prove that the zero algebraic connectivity leads to a zero eigenvalue in the dynamic Jacobian matrix of microgrids and, hence, deteriorates stability. The result reveals the importance of careful planning for DG connection topology especially when a large number of DGs are to be integrated. It also suggests that forming loops by linking the nodes close to feeder terminals could be an effective way for stability enhancement.
AB - In this letter, we theoretically explain that the common connection topology for inverter-based distributed generators (DGs) is harmful to the small-disturbance stability of microgrids. We first prove that the algebraic connectivity of a graph will approach zero in case of inappropriate expansion of nodes and lines. Such type of expansion is often the case in microgrids where new DGs are simply connected to the nearby nodes via single lines that leads to a tree-like structure. Furthermore, we prove that the zero algebraic connectivity leads to a zero eigenvalue in the dynamic Jacobian matrix of microgrids and, hence, deteriorates stability. The result reveals the importance of careful planning for DG connection topology especially when a large number of DGs are to be integrated. It also suggests that forming loops by linking the nodes close to feeder terminals could be an effective way for stability enhancement.
KW - Algebraic connectivity
KW - distributed generator
KW - microgrid
KW - stability
UR - https://www.scopus.com/pages/publications/85071752494
U2 - 10.1109/TPWRS.2019.2917624
DO - 10.1109/TPWRS.2019.2917624
M3 - Article
AN - SCOPUS:85071752494
SN - 0885-8950
VL - 34
SP - 3970
EP - 3972
JO - IEEE Transactions on Power Systems
JF - IEEE Transactions on Power Systems
IS - 5
ER -