考虑频率约束及风电机组调频的风电穿透功率极限计算

Calculation of Wind Power Penetration Limit Involving Frequency Constraints and Frequency Regulation of Wind Turbines

随着风电渗透率持续增加以及虚拟惯性/一次调频控制技术逐步推广应用,准确计算风电穿透功率极限对于确保电网安全稳定运行和指导风电并网规划建设具有重要意义。为此,文中定量表征了风电场虚拟惯性响应特性,并采用传递函数模型表示风电场一次调频响应特性,进而建立了包含风电场、同步发电机组调频控制的电网等值转子摇摆方程,用于描述电力系统频率响应特性。在此基础上,以电网稳态频率偏差约束和频率变化率约束为边界条件,提出了风电穿透功率极限的解析求解方法。最后,通过IEEE 14节点系统算例验证了所提方法的精确性和有效性。

With the continuous increase of penetration level of wind power,and the step-by-step promotion and application of virtual inertia and primary frequency control technology,the accurate calculation of wind power penetration limit has important significance to ensure the safe and stable operation of power grid and to guide the planning and construction of wind power integration system.For this purpose,the inertial response of wind farm is expressed quantitatively,and the primary frequency regulation response of wind farm is described by employing transfer function model.Furthermore,swing equations of an equivalent rotor,including the frequency regulation control of synchronous generator and wind turbine,are established to describe the frequency response characteristics of power system.On this basis,taking the grid steady-state frequency deviation and frequency change rate constraints as boundary conditions,an analytic solution method for calculating the wind power penetration limit is proposed.Finally,the accuracy and effectiveness of the proposed method are verified by case studies of IEEE 14-bus power system.