In the rapidly evolving landscape of power grids, where the integration of renewable energy sources is accelerating, a groundbreaking study led by Jun Qi from the College of Information Engineering at Zhejiang University of Technology in Hangzhou, China, is set to revolutionize frequency regulation. The research, published in the journal Energies, introduces a novel approach to tackle the challenges posed by virtual power plants (VPPs) and their inherent control delays, offering a promising solution for enhancing grid stability and reliability.
As the world races towards “carbon peak” and “carbon neutrality” goals, the influx of renewable energy into power grids has significantly reduced system inertia. This shift, while beneficial for the environment, has introduced new challenges in maintaining grid stability. Frequency volatility and voltage fluctuations have become more pronounced, threatening power quality and grid reliability. Enter virtual power plants, which aggregate distributed energy resources to provide ancillary services, including precise frequency regulation and dynamic peak shaving.
However, the coordination of these distributed flexible resources is not without its hurdles. Communication delays, in particular, have emerged as a critical issue. “Communication delays can significantly impact the effectiveness of frequency regulation,” explains Qi. “Our study addresses this problem by proposing a time-delay-compensated distributed model predictive control (TDC-DMPC) strategy.”
The TDC-DMPC strategy developed by Qi and his team is a significant advancement in the field of distributed frequency control. By incorporating a hierarchical frequency regulation architecture and a delay-embedded generalized predictive model, the strategy systematically integrates historical state reconstruction and future trajectory prediction. This approach allows for the generation of optimal frequency regulation control sequences, even in the presence of communication delays.
The implications for the energy sector are profound. Traditional frequency regulation methods often struggle with the variability and response delays of flexible resources. The TDC-DMPC strategy, however, offers a robust solution that can significantly improve the dynamic response capability of multi-area grids. In simulations conducted on a four-area interconnected power system, the TDC-DMPC strategy reduced frequency deviations by 30.5% and 18.8% compared to conventional and sequence-selective DMPC methods, respectively. Moreover, it achieved a fivefold improvement in stabilization time, reducing it from 2.2 seconds to just 0.4 seconds.
The robustness of the TDC-DMPC strategy was further validated under extreme conditions, including communication delays of up to 600 milliseconds and parameter perturbations of 20%. The system maintained stable operation, demonstrating exceptional resilience and outperforming existing methods in stress scenarios.
“This research provides a new idea for flexible frequency regulation in an environment with a high percentage of new energy access,” says Qi. “By incorporating VPPs into the regional grid cooperative frequency regulation system, we can reduce dependence on traditional thermal power frequency regulation and improve overall system flexibility.”
The commercial impacts of this research are far-reaching. As the energy sector continues to transition towards renewable sources, the need for advanced frequency regulation strategies will only grow. The TDC-DMPC strategy offers a scalable and adaptable solution that can be integrated into existing grid infrastructures, enhancing their stability and reliability.
Looking ahead, the research team plans to conduct hardware-in-the-loop (HIL) testing to verify the real-time performance of the TDC-DMPC strategy. They also aim to combine online parameter identification techniques to further optimize control adaptability under stochastic delay scenarios. These efforts will pave the way for the practical application of the TDC-DMPC strategy in real-world power systems, supporting the construction of a sustainable energy system.
As the energy sector continues to evolve, the work of Jun Qi and his team at Zhejiang University of Technology stands as a testament to the power of innovation in addressing complex challenges. Their research, published in Energies, is set to shape the future of frequency regulation, offering a glimpse into a more stable and reliable power grid.
