TY - JOUR
T1 - An Integrated Synchronization and Control Strategy for Parallel-Operated Inverters Based on V-I Droop Characteristics
AU - Cao, Wenyuan
AU - Han, Minxiao
AU - Zhang, Xiahui
AU - Guan, Yajuan
AU - Guerrero, Josep M.
AU - Vasquez, Juan
N1 - Publisher Copyright:
IEEE
PY - 2022/5
Y1 - 2022/5
N2 - Voltage-current (V-I) droop control is becoming a promising alternative to achieve proper power sharing among the parallel-operated voltage-sourced inverters (VSIs). Compared with the conventional droop control, this method has a simpler structure and a better dynamic performance because it saves the power loop (including the low-pass filters). However, due to the absence of the power loop related to the system frequency, the synchronization of VSIs becomes an intractable issue. To tackle this, a communication-free algorithm to synchronize and control the VSIs is proposed. Initially, the principle of V-I droop control is presented straightforwardly based on the virtual impedance. Then, a synchronization algorithm is incorporated into the V-I droop controller for accurate power sharing. This algorithm adaptively adjusts the phase step of each VSI according to the phase differences between VSI and the ac bus. In this way, the phase differences of each VSI to the ac bus eventually converge to an identical value, thus realizing the synchronization of VSIs. A detailed parameter design method is also implemented considering both system stability and power quality. Finally, the proposed strategy is validated experimentally using a three-parallel-VSIs system.
AB - Voltage-current (V-I) droop control is becoming a promising alternative to achieve proper power sharing among the parallel-operated voltage-sourced inverters (VSIs). Compared with the conventional droop control, this method has a simpler structure and a better dynamic performance because it saves the power loop (including the low-pass filters). However, due to the absence of the power loop related to the system frequency, the synchronization of VSIs becomes an intractable issue. To tackle this, a communication-free algorithm to synchronize and control the VSIs is proposed. Initially, the principle of V-I droop control is presented straightforwardly based on the virtual impedance. Then, a synchronization algorithm is incorporated into the V-I droop controller for accurate power sharing. This algorithm adaptively adjusts the phase step of each VSI according to the phase differences between VSI and the ac bus. In this way, the phase differences of each VSI to the ac bus eventually converge to an identical value, thus realizing the synchronization of VSIs. A detailed parameter design method is also implemented considering both system stability and power quality. Finally, the proposed strategy is validated experimentally using a three-parallel-VSIs system.
KW - Frequency control
KW - Impedance
KW - Inverters
KW - Power harmonic filters
KW - Resistance
KW - Synchronization
KW - synchronization algorithm
KW - virtual impedance
KW - Voltage control
KW - Voltage-current droop
KW - voltage-sourced inverter
UR - http://www.scopus.com/inward/record.url?scp=85121784673&partnerID=8YFLogxK
U2 - 10.1109/TPEL.2021.3135461
DO - 10.1109/TPEL.2021.3135461
M3 - Journal article
AN - SCOPUS:85121784673
SN - 0885-8993
VL - 37
SP - 5373
EP - 5384
JO - IEEE Transactions on Power Electronics
JF - IEEE Transactions on Power Electronics
IS - 5
ER -