Article,
Synchronization Stability Analysis Under Ultra-Weak Grid Considering Reactive Current Dynamics
Contributors
Sahoo, Subham Kumar
0000-0002-7916-028X
[2]
Nian, Heng
0000-0003-4816-084X
[1]
Blaabjerg, Frede
0000-0001-8311-7412
[2]
Affiliations
- [1] Zhejiang University [NORA names: China; Asia, East];
- [2] Aalborg University [NORA names: AAU Aalborg University; University; Denmark; Europe, EU; Nordic; OECD];
- [3] NingboTech University [NORA names: China; Asia, East]
Abstract
The synchronization stability of grid-following converter has attracted extensive attention. It has been reported that the transient synchronization behavior during a grid fault is dominated by the phase-locked loop (PLL), while the current loop is always approximated as a unity gain. Nevertheless, this letter notices that the reactive current dynamics will also influence the synchronization stability under ultra-weak grid, which increases the risk of losing synchronization, and causes the PLL output frequency to be outside the limitation. Accordingly, a refined fourth-order model is proposed to reveal the above underlying mechanism and quantify this coupling effect.
Keywords
PLL output frequency,
analysis,
attention,
behavior,
converter,
coupling,
coupling effect,
current dynamics,
dynamics,
effect,
extensive attention,
fault,
frequency,
grid,
grid faults,
grid-following converters,
letter,
limitations,
loop,
mechanism,
output frequency,
phase-locked loop,
risk,
stability,
stability analysis,
synchronization,
synchronization behavior,
synchronization stability,
synchronization stability analysis
