光伏并网对配电网故障特性以及保护研究  

Research on the fault characteristics and protection of photovoltaic grid-connected distribution network

作　　者：陈天成 唐萃 许耀琦 徐琪 刘健[1] CHEN Tiancheng;TANG Cui;XU Yaoqi;XU Qi;LIU Jian(School of Electrical Information,Wuhan Institute of Technology,Wuhan 430205,China)

机构地区：[1]武汉工程大学电气信息学院,湖北武汉430205

出　　处：《电气应用》2024年第10期61-68,共8页Electrotechnical Application

基　　金：武汉工程大学科学研究基金项目(K201906)。

摘　　要：首先,采用PSCAD构建光伏并网系统故障仿真模型,并结合理论仿真分析了正常运行时光伏并网前后对电气量的影响,重点仿真分析了含光伏并网的配电网中故障类型、故障位置和过渡电阻等因素对故障特性的影响;然后,理论分析了故障类型、故障位置和过渡电阻对光伏并网距离保护的影响,并对相关距离保护进行了仿真分析。研究表明,光伏并网的位置会加剧电网中各种故障(如故障位置、故障类型和过渡电阻等)对电气量的影响,并且会对距离保护产生明显的影响。当光伏并网距故障位置越近时,对电网电气量的影响越大。在各种故障类型中,当光伏并网于固定位置时,考察到单相接地故障对系统电气量的影响更大;故障位置距光伏并网位置越近,距离保护越容易出错。当过渡电阻增大时,光伏模块并网后会促进电压增大。PSCAD is used to construct the fault simulation model of photovoltaic grid-connected system,and the influence of photovoltaic grid-connected on electrical quantity before and after normal operation is analyzed theoretically and simulated.The influence of fault type,fault location,transition resistance and other factors on fault characteristics in distribution network with photovoltaic grid-connected is simulated and analyzed.The influence of fault type,fault location and transition resistance on photovoltaic grid-connected distance protection is analyzed theoretically,and the related distance protection is simulated and analyzed.Studies have shown that the location of photovoltaic grid-connected aggravates various faults in the power grid,such as the influence of fault location,fault type,transition resistance,etc.on electrical quantities,and have a significant impact on distance protection.When the photovoltaic grid is closer to the fault location,the greater the impact on the electrical quantity of the power grid;among various fault types,when the photovoltaic grid is connected to a fixed position,the influence of single-phase grounding fault on the electrical quantity of the system is greater,when the transition resistance increases,the photovoltaic module will promote the voltage increase after grid connection;when the photovoltaic grid is connected to a fixed position,the closer the fault position is to the photovoltaic grid-connected position,the easier the distance protection is to make mistakes.

关 键 词：光伏并网 故障类型 故障位置 过渡电阻 距离保护 

分 类 号：TM615[电气工程—电力系统及自动化]