In the rapidly evolving landscape of energy storage, a groundbreaking strategy has emerged that promises to revolutionize the way distributed energy storage systems (DESS) operate. Researchers from the School of Automation at Guangdong University of Technology and the State Key Laboratory of High-Efficiency and High-Quality Conversion for Electric Power have developed a novel approach to state-of-charge (SOC) balancing, which could significantly enhance the efficiency and reliability of energy storage solutions.
At the heart of this innovation is a method that uses sinusoidal signal injection to address common issues in DESS, such as unbalanced SOC, uneven load current sharing, and unstable direct current (DC) bus voltage. The lead author, Ling Yang, explains, “Our strategy directly combines the SOC of distributed energy storage units with the reference current of the current closed-loop using the arc-sin function. This, along with two acceleration factors, enables rapid SOC balancing.”
One of the standout features of this approach is its ability to free itself from the constraints of conventional droop control. By making the frequency of the injected sinusoidal signals inversely proportional to the DC output current of the storage units, the system can overcome the limitations of traditional methods. This innovation is particularly significant for commercial applications, where communication costs can be a major barrier. “The phase difference between the injected sinusoidal signals forms a reactive power circulation, allowing the output current to be proportionally shared by capacity without the need for communication,” Yang elaborates. This not only reduces system communication costs but also enhances the overall efficiency of the energy storage system.
The research, published in the International Journal of Electrical Power & Energy Systems, also addresses the issue of bus voltage compensation. By designing a limiter link and virtual negative impedance, the system can effectively compensate for bus voltage fluctuations, ensuring stable operation. This is crucial for maintaining the integrity and performance of energy storage systems in various commercial and industrial settings.
The implications of this research are far-reaching. As the demand for renewable energy sources continues to grow, the need for efficient and reliable energy storage solutions becomes increasingly critical. This new SOC balancing strategy could pave the way for more robust and cost-effective DESS, making renewable energy integration more feasible and attractive for businesses and industries.
Yang’s work represents a significant step forward in the field of energy storage. By addressing key challenges and offering innovative solutions, this research has the potential to shape the future of energy storage technology. As the energy sector continues to evolve, such advancements will be essential in meeting the growing demand for sustainable and efficient energy solutions. The energy sector is watching this space closely, anticipating how this research might be commercialized and integrated into existing and future energy infrastructure.
