In the heart of China, researchers are tackling one of the energy sector’s most pressing challenges: ensuring the stability of power grids that receive electricity from multiple ultra-high voltage direct current (UHVDC) sources. This technology is crucial for transmitting power over long distances and in large quantities, but it comes with significant risks if not managed properly. A groundbreaking study, led by Shuyi Shen from the Economic and Technological Research Institute at State Grid Zhejiang Electric Power Co., Ltd., offers a novel solution that could revolutionize how we think about grid stability and power transmission.
The problem is stark: when the stability margin of a power system is insufficient, it can lead to a reduction in DC power transmission, potentially causing blackouts and other catastrophic events. Shen and her team have developed an optimal scheduling method that considers both frequency and voltage stability constraints, providing a robust framework for managing multi-infeed receiving-end power grids.
At the core of their approach is a primary frequency regulation model that derives the frequency stability constraint for the system’s maximum DC transmission power. This model ensures that the grid can handle fluctuations in power supply without compromising stability. “By integrating frequency and voltage stability constraints, we can significantly enhance the reliability of power transmission,” Shen explains. “This is particularly important for regions that rely heavily on UHVDC systems for their energy needs.”
But frequency stability is only half the battle. The researchers also introduced a voltage stiffness index to evaluate the recovery characteristics of high-voltage direct current (HVDC) commutation failures. This index helps establish voltage stability constraints, ensuring that the grid can quickly recover from disturbances. “The voltage stiffness index is a game-changer,” Shen notes. “It allows us to predict and mitigate potential issues before they escalate, making the grid more resilient.”
The optimal scheduling model developed by Shen’s team considers a multitude of operational constraints, including frequency and voltage stability, to create a comprehensive framework for managing multi-infeed receiving-end power grids. The effectiveness of this method was demonstrated through testing on a modified IEEE 39-bus system, showing that it can meet system frequency and voltage stability requirements by adjusting unit commitment and DC power.
The implications for the energy sector are profound. As the demand for long-distance power transmission grows, so does the need for stable and reliable grids. Shen’s research provides a roadmap for achieving this stability, potentially saving energy companies billions in infrastructure costs and preventing costly outages. “This research is not just about improving grid stability,” Shen says. “It’s about building a more resilient and sustainable energy future.”
The study, published in Zhongguo dianli, which translates to ‘China Electric Power,’ marks a significant step forward in the field of power grid management. As energy demands continue to rise, the need for innovative solutions like Shen’s will become increasingly important. The research not only addresses current challenges but also paves the way for future developments in grid technology, ensuring that our energy infrastructure can keep pace with the demands of a rapidly changing world.
