【摘要】 大规模风电注入电网后,部分地区电网末端的风电渗透率超过20%,导致电网中传统的同步发电机维持同步运行的调频压力极大,因此对高渗透率下风电机组参与电网调频时的系统频率等特性进行分析就显得极为重要。对双馈感应风力发电机(DFIG)的虚拟惯量控制及变桨距运行方式进行了研究,提出了风电机组参与电网一、二次调频的控制策略并基于改进后的3机9节点系统搭建了相应的频率响应控制模块,在风电渗透率为40%时分别对不同调频情况下系统频率的变化进行了探究,提出了"调频渗透率"和"调频深度"的概念,在同一模型中不改变电网参数的情况下对比分析了不同调频渗透率或调频深度下系统的频率调整特性。最后验证了调频渗透率及调频深度对于系统频率调整及稳定运行的重要作用,并得出了"高渗透率下留有裕量"的一、二次联合调频策略。更多还原

【Abstract】 In some area,the wind power permeability at the end of power grid exceeding 20% leads to the gradual increasing of frequency modulation pressure for the traditional synchronous generator maintaining synchronous operation after large-scale wind power is connected into the grid.So it is essential to analyze frequency and other characteristics of the system when wind power generators participate in the frequency modulation of power grid under high permeability.After researching the virtual inertia control and variable pitch operation mode of doubly-fed induction generator(DFIG),this paper puts forward the control strategy for DFIGs participating in primary and secondary frequency modulations of power grid and builds the corresponding frequency response control module upon improved 3-unit-9-bus system to respectively explore the changes of system frequency under different frequency modulation conditions in the case of the wind power permeability of 40%.This paper presents the concepts of frequency modulation permeability and frequency modulation depth to comparatively analyze the frequency modulation characteristics of the system under different frequency modulation permeability or depth in the same model without changing parameters of power grid.Lastly,the great effect of frequency modulation permeability and depth on the frequency regulation and operation stability of the system is verified and the combined primary-and-secondary frequency modulation strategy under high permeability with margin is concluded.更多还原