In the dynamic world of power systems, ensuring stable and efficient energy transmission is paramount. A recent study led by Guanhong Wang from the China Electric Power Research Institute in Beijing has shed new light on how to enhance the dynamic stability of long-distance AC transmission systems, a critical aspect for energy delivery from power bases to load centers. The research, published in ‘Zhongguo dianli’ (translated to ‘Chinese Electrical Engineering’), focuses on optimizing the generator excitation control system to bolster transmission capacity, particularly under fault conditions.
The study addresses a common challenge in power systems: insufficient damping during N–1 faults, which can significantly reduce transmission capacity. Wang and his team delved into the intricacies of the excitation system, fine-tuning parameters to enhance the system’s responsiveness and stability. “We optimized the excitation system’s AVR main loop, reactive current compensation, and PSS parameters,” Wang explains. “This reduced the lag time of generators and the excitation system, decreasing the non-compensation phase frequency characteristic hysteresis by 10 degrees.”
The researchers didn’t stop at initial optimizations. They further refined the phase compensation for PSS parameters, bringing the compensation characteristics closer to –90 degrees. This adjustment substantially increased the AC gain provided by PSS, a crucial factor in maintaining system stability. “The results show that the excitation system and PSS have a significant influence on the dynamic characteristics of the power grid,” Wang notes. “Under the existing parameter configuration, the delivery capacity of the power system cannot meet the full power generation requirements of generator units at the sending end.”
The implications of this research are profound for the energy sector. By implementing the optimized parameter configuration, power grids can meet the safe operation requirements of generator units and power grids more effectively. This means that during N–1 faults, the transmission system can handle higher loads, improving overall efficiency and reliability. For commercial entities, this translates to reduced downtime, lower operational costs, and enhanced service reliability—a boon for both utilities and consumers.
The study’s findings underscore the importance of coordinated optimization in power system control. As energy demands continue to rise and grids become more complex, such advancements will be pivotal in ensuring stable and efficient power delivery. The research by Wang and his team at the China Electric Power Research Institute not only provides a roadmap for immediate improvements but also sets a precedent for future developments in the field. As we move towards a more interconnected and resilient energy infrastructure, the insights from this study will undoubtedly shape the future of power system control and optimization.
