Stability analysis on islanded microgrids with grid-forming and grid-following converters

doi:10.3969/j.issn.2097-0706.2024.02.002

Abstract

Abstract:

There is stability problem in islanded microgrids dominated by electronic devices resulting from low system inertia and no frequency support，which is aggravated by constant-power load. Thus， the islanded microgrids with grid-forming and grid-following converters are studied with constant-power load taken into consideration. First， a small-signal model of a microgrid power system is developed. And the upper limit of the grid-forming converters' droop coefficient is obtained from the study on the impacts of droop coefficients on the stability by eigenvalue analysis. Then， the influences of system parameters and control parameters on the stability of small signals are analysed by participation factor. Finally， the analytical results are examined by the switching-function model constructed in Matlab Simulink.

Key words: grid-forming converter, grid-following converter, islanded microgrid, constant power load, small-signal stability, droop coefficient, new power system

CLC Number:

TM712

ZHANG Xinyi, YANG Bo. Stability analysis on islanded microgrids with grid-forming and grid-following converters[J]. Integrated Intelligent Energy, 2024, 46(2): 12-18.

Figures/Tables 9

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参数	数值	参数	数值
变流器额定容量/(kV·A)	115	V_n/V	400
P_n/kW	100	ω_n/(rad·s^-1)	314
Q_n/（kV·A）	0	L_ft/mH	0.045
L_fg/mH	0.030	C_f/mF	0.7
C_dc/mF	13.0	m_p	1×10^-4
n_q	6×10^-5	F_i,F_v	1
ω_c/(rad·s^-1)	30	R_line/Ω	0.01
L_line/mH	0.100	R_N/Ω	1 000
P_cpl/kW	150	C_dc/mF	5
L_gt/mH	0.100	L_gl/mH	0.002
C_g/mF	1.5	isqref/A	0