面向频率稳定校核的风机快速频率响应低阶建模方法及其误差分析

Low-order Modeling of Wind Turbine-based Fast Frequency Response and Its Error Analysis for Frequency Stability Assessment

风机快速频率响应能够有效保障高比例风电电力系统频率稳定性,已逐步进入实用化阶段。风机快速频率响应影响传统机组安排,需在调频参数设计、调度运行等优化问题的频率稳定校核约束中予以考虑。为提高频率稳定校核效率,线性化的系统频率响应低阶模型应用广泛。然而,风机调频特性区别于传统机组,运行特性的非线性特征显著,其快速频率响应低阶模型尚缺乏归纳整理,且计算误差分析尚不完善。文中分类整理了风机快速频率响应策略;针对不同响应策略,给出风机低阶模型的通用建模方法及调频特性分析方法;理论分析低阶模型的线性化误差,并通过数值仿真予以验证。该文可为风机快速频率响应低阶模型的选择、推导及误差分析提供参考。

Wind turbine-based fast frequency response is being used in industrial circles gradually, because it can effectively guarantee the frequency stability of power systems with high wind power penetration. The fast frequency response affects daily scheduling of traditional generators, indicating that fast frequency response should be considered in frequency stability assessment constraints of power system optimization,like parameter design and optimal power flow problems. To improve the efficiency of frequency stability assessment, the linearized low-order model has been widely adopted. Unlike traditional generators, wind turbines’ nonlinear characteristic is significant in frequency studies. However, the low-order model of wind turbine-based fast frequency response has not been well summarized, and the linearization error analysis of the model needs further investigations. In this paper, classical fast frequency response strategies were reviewed, and a generic low-order model formulation approach was presented. With the model, the frequency regulation characteristics of each strategy were fully studied. Theoretical analysis of the low-order model was carried out, and the validity was verified by numerical simulations. This paper can provide a guideline for selection,formulation, and error analysis of the low-order model of wind turbine-based fast frequency response.