TY - JOUR
T1 - Closed-Form Solutions for Grid-Forming Converters
T2 - A Design-Oriented Study
AU - Zhao, Fangzhou
AU - Zhu, Tianhua
AU - Harnefors, Lennart
AU - Fan, Bo
AU - Wu, Heng
AU - Zhou, Zichao
AU - Sun, Yin
AU - Wang, Xiongfei
N1 - Publisher Copyright:
© 2020 IEEE.
PY - 2024
Y1 - 2024
N2 - This paper derives closed-form solutions for grid-forming converters with power synchronization control (PSC) by subtly simplifying and factorizing the complex closed-loop models. The solutions can offer clear analytical insights into control-loop interactions, enabling guidelines for robust controller design. It is proved that 1) the proportional gains of PSC and alternating voltage control (AVC) can introduce negative resistance, which aggravates synchronous resonance (SR) of power control, 2) the integral gain of AVC is the cause of sub-synchronous resonance (SSR) in stiff-grid interconnections, albeit the proportional gain of AVC can help dampen the SSR, and 3) surprisingly, the current controller that dampens SR actually exacerbates SSR. Controller design guidelines are given based on analytical insights. The findings are verified by simulations and experimental results.
AB - This paper derives closed-form solutions for grid-forming converters with power synchronization control (PSC) by subtly simplifying and factorizing the complex closed-loop models. The solutions can offer clear analytical insights into control-loop interactions, enabling guidelines for robust controller design. It is proved that 1) the proportional gains of PSC and alternating voltage control (AVC) can introduce negative resistance, which aggravates synchronous resonance (SR) of power control, 2) the integral gain of AVC is the cause of sub-synchronous resonance (SSR) in stiff-grid interconnections, albeit the proportional gain of AVC can help dampen the SSR, and 3) surprisingly, the current controller that dampens SR actually exacerbates SSR. Controller design guidelines are given based on analytical insights. The findings are verified by simulations and experimental results.
KW - Grid-connected converter
KW - grid-forming control
KW - stability
KW - sub-synchronous resonance
KW - synchronous resonance
UR - https://www.scopus.com/pages/publications/85184010548
U2 - 10.1109/OJPEL.2024.3357128
DO - 10.1109/OJPEL.2024.3357128
M3 - 文章
AN - SCOPUS:85184010548
SN - 2644-1314
VL - 5
SP - 186
EP - 200
JO - IEEE Open Journal of Power Electronics
JF - IEEE Open Journal of Power Electronics
ER -