光伏虚拟同步发电机建模与仿真研究

Research on modeling and simulation of photovoltaic virtual synchronous generator

为提高光伏虚拟同步发电机建模的准确性,给出了计及光伏输出最大功率点跟踪、储能、并网逆变器于一体的光伏虚拟同步发电机的建模方法。首先,考虑光伏阵列及蓄电池储能的输出特性,分直流和交流两部分建模,得到其各自的输出功率数学模型。其次,结合光伏输出最大功率点跟踪和储能的双环控制,提出一种分层协调的虚拟同步发电机控制策略,给出光伏虚拟同步发电机四种运行模式,并综合交直流输出特性,获得光伏虚拟同步发电机四模式运行的等效输出静态模型。最后,通过Matlab/Simulink平台搭建了光伏虚拟同步发电机的仿真模型。仿真结果验证了所建模型的准确性及控制策略的有效性。

In order to improve the accuracy of PV virtual synchronous generator modeling,the modeling method of photovoltaic virtual synchronous generator integrating the maximum power point tracking,energy storage and grid-connected inverter is presented.Firstly,considering the output characteristics of photovoltaic array and battery energy storage,modeling is divided into DC part and AC part to obtain their respective output power mathematical models.Secondly,combining the maximum power tracking of PV output and the dual-loop control of energy storage,a hierarchical and coordinated virtual synchronous generator strategy is proposed,and four operating modes of photovoltaic virtual synchronous generator are given,then by synthesizing the DC/AC output characteristics,the equivalent output static model of the four modes operation of the photovoltaic virtual synchronous generator is obtained.Finally,the simulation model of the photovoltaic virtual synchronous generator is built through the Matlab/Simulink platform,the simulation results verify the accuracy of the model and the effectiveness of the control strategy.