摘要
随着新能源与储能系统并网工程的不断建设,部分新能源、储能、静止无功发生器(static var generator,SVG)与传统火电通过一个升压站并入电网,构成了复杂的多电源“打捆送出”系统,其相互作用引起的振荡问题也开始显现出来。首先,为评估多电源并网系统宽频振荡的风险,采用单机阻抗建模-对比验证-整系统阻抗建模的思路,从等效阻抗的角度阐明了多电源并网系统宽频振荡的机理,分析了不同频段的幅频曲线特征与控制参数的影响,利用在线阻抗测量法对多电源系统的阻抗特性建模,具体分为基于硬件在环仿真的单机阻抗建模、基于电磁模型的单机阻抗建模、电磁暂态仿真与硬件在环对比验证、基于电磁模型的整站阻抗建模4个步骤。然后,通过系统短路比得到大电网的阻抗特性。最终,根据奈奎斯特定理来判定多源系统与大电网之间有无宽频振荡的风险,分析了单一工况幅频曲线的特征,明确了与大电网振荡风险的评估流程,为宽频域振荡评估与控制提供指导思路。
With the continuous construction of grid-connected projects for new energy and energy storage systems,some new energy,energy storage,static var generators(SVG),and conventional thermal power are connected to the grid through a step-up substation,forming a complex multi-source"bundled transmission"system.Oscillation issues arising from their interactions have begun to emerge.To assess the risk of wide-frequency oscillations in multi-source grid-connected systems,the approach of single-machine impedance modeling-comparison verification-whole-system impedance modeling is adopted.First,the mechanism of wide-area oscillations in multi-source grid-connected systems is clarified from the perspective of equivalent impedance,analyzing the characteristics of amplitude-frequency curves and the influence of control parameters across different frequency bands.The impedance characteristics of multi-source systems are modeled using online impedance measurement methods,specifically divided into four steps:single-machine impedance modeling based on hardware-in-the-loop simulation,single-machine impedance modeling based on electromagnetic models,electromagnetic transient simulation and hardware-in-the-loop comparative vertification,and whole-system impedance modeling based on electromagnetic models.Then,the impedance characteristics of the bulk power grid are obtained through the system short-circuit ratio.Finally,according to the Nyquist criterion,the presence of widearea oscillation risks between the multi-source system and the large grid is determined.The characteristics of amplitudefrequency curves under single operating conditions are analyzed,clarifying the assessment process for oscillation risks with the large grid,providing guidance for wide-frequency oscillation assessment and control.
作者
王磊
唐欢喜
WANG Lei;TANG Huanxi(CYG SUNRI Co.,Ltd.,Shenzhen 518000,China)
出处
《河北电力技术》
2025年第6期1-11,共11页
Hebei Electric Power
关键词
宽频振荡
多电源系统
阻抗特性
硬件在环仿真
broadband oscillation
multi-power system
impedance characteristics
hardware in the loop simulation
