Abstract
This article analyzes the transient stability of grid-following voltage source converters (GFL-VSCs) considering the voltage-dependent current injection (VDCI) dynamics during fault ride-through (FRT). The dynamic interaction between the VDCI and the phase-locked loop (PLL) under the weak grid is revealed to provide insight for their impact on system transient stability. The condition of existence of equilibrium points (EPs) of VSC-grid system during grid faults is first investigated by using a static model considering the VDCI. Then, a dynamic model is developed to characterize the capability of VSC in converging to the EPs during grid faults. It is revealed that the <italic>K</italic>-factor, which determines the characteristic of the VDCI, has a crucial impact on the transient stability of the system. Finally, case studies based on electromagnetic transient (EMT) simulation and experiment are given to validate the theoretical findings.
| Original language | English |
|---|---|
| Journal | IEEE Transactions on Energy Conversion |
| Volume | 37 |
| Issue number | 4 |
| Pages (from-to) | 2749-2760 |
| Number of pages | 12 |
| ISSN | 0885-8969 |
| DOIs | |
| Publication status | Published - 1 Dec 2022 |
Keywords
- Fault ride-through (FRT)
- Numerical stability
- Phase locked loops
- Power system dynamics
- Power system stability
- Stability criteria
- Synchronization
- Transient analysis
- grid-following converters
- transient stability
- voltage-dependent current injection (VDCI)