In the dynamic world of renewable energy, the integration of wind power into the grid has long posed challenges, particularly in maintaining system frequency stability. Traditional wind turbines, operating under Variable Speed Constant Frequency (VSCF) conditions, have struggled to actively respond to frequency changes due to the decoupling of rotor speed and system frequency. However, a groundbreaking study led by Tianxiang Wang from the Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education at Shandong University, Jinan, China, is set to revolutionize how wind farms contribute to grid stability.
The research, published in ‘Zhongguo dianli’ (Chinese Journal of Electrical Engineering), introduces an innovative active power control strategy for wind farms. This strategy leverages overspeed de-loading control for wind turbines operating in low wind speed zones, maximizing the kinetic energy stored in the rotating mass. Simultaneously, it employs pitch angle control for turbines in high wind speed zones to meet the system’s reserve demand as required by the transmission system operator.
Wang explains, “By preferentially applying overspeed de-loading control, we can ensure that the wind turbines operating in low wind speed zones are fully utilized, storing as much kinetic energy as possible.” This approach not only optimizes energy storage but also prepares the turbines to respond swiftly to frequency fluctuations.
The strategy doesn’t stop at energy storage. It also introduces a virtual inertial control strategy with variable parameters, fine-tuning the droop coefficient to fully release the reserve power of the wind turbines during system frequency regulation. This dual approach ensures that wind farms can actively participate in primary frequency control, a critical aspect of grid stability.
The implications for the energy sector are profound. As wind power continues to grow as a significant portion of the global energy mix, the ability to integrate it seamlessly into the grid becomes paramount. This research paves the way for wind farms to become more than just power generators; they can now act as dynamic participants in grid stability, responding to frequency changes with precision and efficiency.
Wang’s work, built on a system simulation model in DIgSILENT, demonstrates that the proposed strategy can reasonably allocate reserve power and effectively use it to respond to system frequency changes. This breakthrough could lead to more reliable and stable grids, reducing the need for traditional, often fossil-fuel-based, backup power sources.
The commercial impacts are equally significant. Energy providers can now consider wind farms as reliable assets for frequency control, potentially reducing operational costs and enhancing grid resilience. This could spur further investment in wind energy, accelerating the transition to a more sustainable energy landscape.
As the energy sector continues to evolve, research like Wang’s will be pivotal in shaping future developments. By enhancing the capabilities of wind farms to contribute to grid stability, we move closer to a future where renewable energy sources are not just part of the energy mix but the backbone of a stable and sustainable power grid.
