TY - JOUR
T1 - Impedance-Based Analysis of DC-Link Voltage Dynamics in Voltage-Source Converters
AU - Lu, Dapeng
AU - Wang, Xiongfei
AU - Blaabjerg, Frede
PY - 2019/4
Y1 - 2019/4
N2 - This paper addresses the stability issues caused by the dc-link voltage control of grid-connected voltage-source converters. An analytical impedance model is developed first for capturing the interactions between the dc-link voltage control and ac current control of converters, which enables to identify different stability impacts of the dc-link voltage control in the rectifier and inverter operation modes of converters. The impedance model is further transformed from the dq-frame to the αβ-frame, which allows characterizing the frequency-coupling effects of the dc-link voltage control dynamics. The impedance-based analysis reveals that the dc-link voltage control may cause low-frequency oscillations in the rectifier mode and high-frequency oscillations in the inverter mode. Case studies on the rectifier and inverter operation modes are presented, and subsequently validated by using time-domain simulations and experimental tests. The close correlations between the measured results and theoretical analysis demonstrate the effectiveness of the impedance model and stability analysis.
AB - This paper addresses the stability issues caused by the dc-link voltage control of grid-connected voltage-source converters. An analytical impedance model is developed first for capturing the interactions between the dc-link voltage control and ac current control of converters, which enables to identify different stability impacts of the dc-link voltage control in the rectifier and inverter operation modes of converters. The impedance model is further transformed from the dq-frame to the αβ-frame, which allows characterizing the frequency-coupling effects of the dc-link voltage control dynamics. The impedance-based analysis reveals that the dc-link voltage control may cause low-frequency oscillations in the rectifier mode and high-frequency oscillations in the inverter mode. Case studies on the rectifier and inverter operation modes are presented, and subsequently validated by using time-domain simulations and experimental tests. The close correlations between the measured results and theoretical analysis demonstrate the effectiveness of the impedance model and stability analysis.
KW - DC-link voltage control
KW - Frequency-coupling
KW - Impedance model
KW - Stability
KW - Voltage-source converters (VSCs)
UR - http://www.scopus.com/inward/record.url?scp=85051808320&partnerID=8YFLogxK
U2 - 10.1109/TPEL.2018.2856745
DO - 10.1109/TPEL.2018.2856745
M3 - Journal article
SN - 0885-8993
VL - 34
SP - 3973
EP - 3985
JO - IEEE Transactions on Power Electronics
JF - IEEE Transactions on Power Electronics
IS - 4
M1 - 8440759
ER -