面向宽频段谐振分析的集中式光伏电站单机等值模型适用性分析  

Applicability analysis of single-unit equivalent model of centralized photovoltaic power station for wide-band resonance

作　　者：谢宇哲 王杨 贺艳华 陈海盟 XIE Yuzhe;WANG Yang;HE Yanhua;CHEN Haimeng(Ningbo Power Supply Company,State Grid Zhejiang Electric Power Co.,Ltd.Ningbo 315000,China;College of Electrical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]国网浙江省电力有限公司宁波供电公司,浙江宁波315000 [2]四川大学电气工程学院,四川成都610065

出　　处：《热力发电》2024年第4期9-18,共10页Thermal Power Generation

基　　金：宁波永耀电力投资集团有限公司研发项目(KJXM2022059)。

摘　　要：近年来,国内外发生了多起涉及新能源电站的谐波谐振事故。频率扫描法由于操作简单、物理意义明确等优点,在工程中被广泛应用于系统谐振评估。在建立大型新能源电站电磁暂态仿真模型并进行频率扫描时,通常使用单台或多台机组来代替大型新能源电站,以降低建模复杂度,然而该做法在高频谐波谐振问题中的适用性还未能得到有效揭示。为此,以某大型光伏电站为例,利用自下而上建模法建立了光伏电站详细阻抗模型,并在此基础上采用等功率损耗原则建立了其动态等值模型,通过实际场站参数对2种模型进行了详细的对比分析。研究结果表明,集电线路串联阻抗对于谐波模型影响较小。为此提出了采用对地电容代替π型电路的简化动态等值模型。通过等功率损耗法建立的等值模型可以准确反映光伏电站的谐波谐振特性,而忽略集电线路电感所得的等值模型适用于分析光伏电站的中低次谐波谐振分析。In recent years,numerous incidents of harmonic resonance accidents involving new energy power stations have occurred both domestically and internationally.The frequency scanning method,characterized by its simplicity of operation and clear physical significance,has been widely employed in engineering for the assessment of system resonance.When establishing electromagnetic transient simulation models for large-scale new energy power stations and conducting frequency scans,it is common to substitute a single or multiple generators for the actual power station to reduce modeling complexity.However,the applicability of this approach in addressing high-frequency harmonic resonance issues has not been effectively revealed.To address this gap,this study takes a large-scale photovoltaic power station as an example and employs a bottom-up modeling approach to establish a detailed impedance model for the photovoltaic power station.Building upon this,a dynamic equivalent model is developed using the principle of equal power loss.The two models are then thoroughly compared and analyzed based on actual field station parameters.The research findings indicate that the series impedance of the collector lines has a minimal effect on the harmonic model.As a result,the study proposes a simplified dynamic equivalent model replacing theπ-type circuit with a ground capacitor.The results demonstrate that the equivalent model established through the equal power loss method accurately reflects the harmonic resonance characteristics of the photovoltaic power station.Additionally,the model neglecting the inductance of the collector lines proves applicable for analyzing the mid-to-low frequency harmonic resonance in photovoltaic power stations.

关 键 词：大型光伏电站 动态等值 适用性 谐振 谐波谐振 

分 类 号：TM615[电气工程—电力系统及自动化]