大规模光伏电站并网的振荡模式分析  

Analysis on oscillation modes of large-scale grid-connected PV power plant

作　　者：高本锋[1] 姚磊[1] 李忍[1] 赵书强[1] 杨琳[2] 

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,河北保定071003 [2]华北电力大学电气与电子工程学院,北京102206

出　　处：《电力自动化设备》2017年第8期123-130,共8页Electric Power Automation Equipment

基　　金：国家自然科学基金资助项目(51507064);中央高校基本科研业务费资助项目(2015MS84)~~

摘　　要：随着光伏电站容量的不断增大,其对于电网稳定性的影响也日趋明显。建立了大规模光伏电站并网系统的等值模型,采用特征值法和时域仿真验证其准确性。基于等值模型采用特征值法分析了大规模光伏电站的振荡模式,并研究了光伏逆变器的控制器参数、光伏阵列结构以及交流系统强弱对振荡模式的影响。仿真结果表明:光伏并网系统中主要包含正阻尼的次同步振荡模式和低频振荡模式,其中次同步振荡模式主要受q轴电流PI参数的影响,低频振荡模式主要受外环电压和d轴电流PI参数的影响;光伏阵列结构的变化对系统振荡模式有影响,会使系统中与直流电压相关的模式由非振荡状态变为振荡状态;交流系统变弱会导致振荡模态阻尼减弱,威胁系统的安全稳定运行。时域仿真验证了特征值分析的正确性。The impact of PV（PhotoVohaic） power plant on the stability of power system becomes more obvious along with its increasing capacity. An equivalent model of large-scale grid-connected PV power plant is established and its accuracy is verified by the eigenvalue method and time-domain simulation. Based on the equivalent model,the eigenvalue method is applied to analyze the oscillation modes of large- scale PV power plant and the influences of PV inverter controller parameters,PV array configuration and AC system strength on the oscillation modes are also researched. Simulative results show that,the grid- connected PV system mainly contains the positive-damping sub-synchronous oscillation mode and the low- frequency oscillation mode,the former is mainly affected by the PI parameters of q-axis current and the latter by the PI parameters of outer loop voltage and d-axis current;the change of PV array configuration may convert the nonoscillating state of DC-vohage-related system mode into the oscillating state;the weakened AC system may reduce the damping of oscillation modes,threatening the safe and stable system operation. Time-domain simulation verifies the correctness of eigenvalue analysis.

关 键 词：光伏电站 小信号模型 等值模型 振荡模式 特征值法 时域仿真 光伏阵列结构 

分 类 号：TM615[电气工程—电力系统及自动化]