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.
出处
《电力自动化设备》
EI
CSCD
北大核心
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)~~
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
photovohaie power plant
small-signal model
equivalent models
oscillation modes
eigenvalue method
time-domain simulation
photovohaic array configuration