In the dynamic world of power grids, maintaining stability is paramount, especially when dealing with high-voltage direct current (HVDC) transmission lines. A recent study led by Jing Gou, from the State Grid Sichuan Power Economic Research Institute in Chengdu, China, sheds light on a critical issue: the sharp drop in inertia of sending-end power grids during bipolar blocking of HVDC lines. This phenomenon can lead to severe high-frequency problems, posing significant risks to grid stability.
Traditional generation shedding strategies, designed to manage these high-frequency issues, often fall short. They can result in inaccurate shedding capacity, leading to either over-shedding or under-shedding, and a lack of rotational inertia post-shedding. This is where Gou’s research comes in, proposing a novel generation shedding capacity optimization model tailored for sending-end grids with multi-DC asynchronous outfeeds.
The model is a comprehensive solution that considers various constraints, including frequency constraints, network power flow constraints, reserve constraints, and generator-tripping capacity. “By taking into account the adjustment performance and geographical distribution differences of various units in the sending-end grid, we can optimize the generation shedding scheme,” Gou explains. The study employs the TOPSIS method and the Superiority Chart to determine penalty factors for different units, ultimately aiming to minimize the comprehensive cost of generator tripping.
The implications for the energy sector are profound. As the world increasingly relies on HVDC transmission for long-distance power transfer, ensuring the stability and efficiency of sending-end power grids becomes crucial. Gou’s model offers a more precise and adaptive approach to managing high-frequency problems, potentially reducing the risk of blackouts and improving overall grid reliability.
The research, published in ‘Zhongguo dianli’ (translated to ‘China Electric Power’), uses an improved IEEE RTS-79 test system to validate its effectiveness and frequency adaptability. The findings suggest that this model could revolutionize how power grids handle bipolar blocking faults in large-capacity HVDC transmission lines.
As the energy sector continues to evolve, with a growing emphasis on renewable energy sources and smart grids, innovations like Gou’s are essential. They pave the way for more resilient and efficient power systems, capable of meeting the demands of a rapidly changing world. This research not only addresses immediate challenges but also sets the stage for future developments in grid stability and optimization.
