In the rapidly evolving landscape of energy transmission, the integration of renewable energy sources has presented unique challenges to grid stability and protection. Traditional backup protection systems, designed for a different era, are struggling to keep up with the complexities introduced by renewable energy. However, a groundbreaking study published by researchers from China Three Gorges University and the State Key Laboratory of Advanced Electromagnetic Engineering and Technology offers a promising solution to these modern grid conundrums.
The research, led by Dr. Lin Xiangning, addresses the dynamic adaptability of backup protection in power grids heavily laden with renewable energy. The study, published in ‘Dianli jianshe’ (translated to ‘Electric Power Construction’), introduces a dual-criteria approach based on wide-area measurements to identify faulty components in transmission grids swiftly and accurately.
“Traditional backup protection systems rely on offline settings, which are not well-suited to the complex conditions of looped networks,” explained Dr. Lin. “The low-inertia and low-voltage ride-through control of renewable energy sources further complicates the characteristics of positive- and negative-sequence networks, making it difficult to identify faulty components.”
To tackle these issues, the researchers proposed a method that uses negative-sequence voltage/current ranking for asymmetrical faults and a traveling wave monitoring device for symmetrical faults. This approach enables rapid identification of fault-associated buses and branches, significantly improving the accuracy and speed of fault detection.
The study’s simulations yielded impressive results. For asymmetrical faults, the negative-sequence criterion achieved a 100% accuracy rate, even with a transition resistance of 30 Ω. For symmetrical faults, the traveling wave ranging error was less than 100 meters, and the location time was reduced by 90% compared to traditional methods. Moreover, the optimization of backup-protection logic reduced the remote backup-action delay from 4-7 intervals to just 2 intervals, enhancing sensitivity and speed.
The implications of this research for the energy sector are profound. As the world transitions to cleaner energy sources, the need for adaptive and reliable grid protection systems becomes increasingly critical. This study provides a robust framework for dynamic identification of faulty components, paving the way for more resilient and efficient power grids.
Dr. Lin and his team’s work not only addresses current challenges but also sets the stage for future developments in grid protection. By leveraging wide-area measurements and advanced algorithms, their approach offers a scalable and reliable solution for online backup protection in power grids with a high proportion of renewable energy.
As the energy sector continues to evolve, innovations like these will be crucial in ensuring the stability and reliability of our power grids. The research published in ‘Electric Power Construction’ marks a significant step forward in this direction, offering a glimpse into the future of grid protection and management.