| Autor: |
Fayou Yan, Puyu Wang, Xiao-Ping Zhang, Jufang Xie, Xiaodong Li, Chao Tang, Zhongyong Zhao |
| Jazyk: |
angličtina |
| Rok vydání: |
2019 |
| Předmět: |
|
| Zdroj: |
IEEE Access, Vol 7, Pp 65093-65102 (2019) |
| Druh dokumentu: |
article |
| ISSN: |
2169-3536 |
| DOI: |
10.1109/ACCESS.2019.2914765 |
| Popis: |
Modular multilevel converter (MMC)-based high-voltage direct current (HVDC) grid is a promising technology for multiple offshore wind farms (OWFs) to form interconnected offshore grids. However, in the MMC-HVdc grid, the converter terminals connecting the OWFs could only be passively pre-charged by the ones connecting active ac networks via the dc lines during the start-up process. Under this condition, the start-up process of HVdc grid of the passive-side converters becomes significantly complicated. This paper, considering an HVdc grid integrating multiple passive-side converters, investigates its start-up process with three main contributions: 1) a modified nearest level modulation (NLM) method is proposed for the passive-side converters to mitigate the inrush currents after they are deblocked; 2) based on the dc-side equivalent models, the inter-converter resonances and oscillations between the passive-side converters are analyzed after they are deblocked, and; 3) an oscillation damping controller is proposed to provide the electrical damping of inter-converter oscillations between the passive-side converters. The simulation results in PSCAD/EMTDC from a four-terminal MMC-HVDC grid with two terminals connecting the OWFs verify the effectiveness of the proposed start-up control schemes. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
|
