基于转子动能的双馈风机频率支撑优化方法

Rotor Kinetic Energy-based Frequency Regulation Optimization Method for DFIG

“双碳”背景下,新能源发电量占比逐年提高,电力系统低惯量、弱阻尼特征显现,双馈风机DFIG(doublyfed induction generator)如何在经济高效运行的同时参与频率支撑,是目前电力系统所面临的主要挑战之一。在双馈风机综合惯量阻尼控制策略的基础上,分析系统的频率动态特性,提出基于风机转子动能的频率支撑策略参数优化设计方法,求解考虑二次频率跌落下满足最小频率偏差的惯量阻尼最优控制系数,最大程度抬升频率最低点,防范系统低频减载等安全稳定措施不必要动作。最后,通过仿真验证了所提基于转子动能的DFIG频率支撑优化方法的正确性和有效性。

In the context of“carbon peaking and carbon neutrality”,the proportion of renewable energy generation is in⁃creasing year by year,and the characteristics of power system such as low inertia and weak damping emerge.There⁃fore,how to make double-fed induction generators(DFIGs)participate in frequency regulation while maintaining their economic and high-efficiency operation is one of the main challenges facing the power system at present.On the basis of a comprehensive inertia and damping control strategy for the DFIG,the system’s frequency dynamicsis analyzed.More⁃over,an optimization design method for frequency regulation parameters based on the rotor kinetic energy of DFIG is proposed.Considering the secondary frequency drop,the control parameters are optimized,which minimizes the fre⁃quency deviation and improves the frequency nadir to the greatest extent possible for preventing the unnecessary actions of safety and stability measures such as under-frequency load shedding.Finally,simulation results validate the correct⁃ness and effectiveness of the proposed method.