Affiliation:
1. Graduate Program of Electrical Engineering, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Brazil
2. Department of Electric and Electronics, Federal Centre of Technological Education of Minas Gerais, Leopoldina 36700-001, Brazil
Abstract
This work presents a control strategy for integrating an offshore wind farm into the onshore electrical grid using a high-voltage dc transmission system based on modular multilevel converters. The proposed algorithm allows the high-voltage DC system to operate in grid-connected or stand-alone modes, with the second case supplying power to local loads. In either mode, the modular multilevel rectifier works as a grid-forming converter, providing the reference voltage to the collector network. During grid-connected operation, the modular multilevel inverter regulates the DC link voltage while the generating units are controlled to maximize power extracted from the wind turbines. Conversely, in the event of grid disconnection, the onshore modular multilevel converter takes over the regulation of the AC voltage at the point of connection to the grid, ensuring energy supply to local loads. Simultaneously, the generator controller transitions from tracking the maximum power of the wind turbines to regulating the DC link voltage, preventing excessive power injection into the transmission DC link. Additionally, the turbine pitch angle control regulates the speed of the generator. Mathematical models in the synchronous reference frame were developed for each operation mode and used to design the converter’s controllers. A digital model of the wind power plant and a high-voltage dc transmission system was implemented and simulated in the PSCAD/EMTDC program. The system modeled includes two groups of wind turbines, generators, and back-to-back converters, in addition to a DC link with a rectifier and an inverter station, both based on modular multilevel converters with 18 submodules per arm, and a 320 kV/50 km DC cable. Aggregate models were used to represent the two groups of wind turbines, where 30 and 15 smaller units operate in parallel, respectively. The performance of the proposed control strategy and the designed controllers was tested under three distinct scenarios: disconnection of the onshore converter from the AC grid, partial loss of a wind generator set, and reconnection of the onshore converter to the AC grid.
Funder
the Coordination for the Improvement of Higher Education Personnel
the National Council for Scientific and Technological Development
the State Funding Agency of Minas Gerais
the National Institute for Electric Energy
he Federal University of Juiz de Fora
Subject
Energy (miscellaneous),Energy Engineering and Power Technology,Renewable Energy, Sustainability and the Environment,Electrical and Electronic Engineering,Control and Optimization,Engineering (miscellaneous),Building and Construction
Reference45 articles.
1. High-power wind energy conversion systems: State-of-the-art and emerging technologies;Yaramasu;Proc. IEEE,2015
2. Anaya-Lara, O., Campos-Gaona, D., Moreno-Goytia, E., and Adam, G. (2014). Offshore Wind Energy Generation: Control, Protection, and Integration to Electrical Systems, John Wiley & Sons.
3. Pan, W., Chang, Y., and Chen, H. (November, January 29). Hybrid multi-terminal HVDC system for large scale wind power. Proceedings of the 2006 IEEE PES Power Systems Conference and Exposition, Atlanta, GA, USA.
4. Integration of large scale wind generation using HVDC and power electronics;Andersen;CIGRE Publ. Work. Group B,2009
5. Review of VSC HVDC connection for offshore wind power integration;Korompili;Renew. Sustain. Energy Rev.,2016
Cited by
4 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献