基于二阶线性自抗扰的虚拟同步发电机二次调频控制

Secondary Frequency Modulation Control of Virtual Synchronous Generator Based on Second-order Linear Active Disturbance Rejection Control

当分布式电源处于孤岛运行时,负载的突变或切入/切出会引起虚拟同步发电机系统频率的突变。针对该问题提出基于二阶线性自抗扰的虚拟同步发电机系统频率无差调节策略;并与分析得到的系统输出频率二阶模型相结合,从系统稳定性角度出发对自适应控制参数进行整定,使虚拟同步发电机在孤岛状态下发生负载突增时,能够实现对系统频率无差调节,达到二次调频的目的。最后将所提出的控制策略在MATLAB/Simulink中进行仿真实验,与基于PI调节阻尼系数的控制方法进行对比,仿真结果验证了所提控制策略的有效性和正确性。

When a distributed generation is operating in island mode,a sudden change in load or cut in/out will cause an abrupt frequency variation to a virtual synchronous generator(VSG)system.In view of this operation condition,a frequency deviation-free regulation strategy for the VSG system based on second-order linear active disturbance rejec⁃tion control is proposed,which is combined with the second-order model of system output frequency obtained through analysis.From the perspective of system stability,the adaptive control parameters are adjusted,so that the deviation-free regulation of system frequency can be realized when the VSG is operating in island mode and under a sudden in⁃crease in load,thus realizing the objective of secondary frequency modulation.Finally,simulation verification is com⁃pleted in MATLAB/Simulink,and a comparison with the existing control method based on PI damping coefficient adjustment is performed.Simulation results verify the effectiveness and correctness of the proposed control strategy.