计及阻尼特性的构网型并网逆变器暂态同步稳定性分析

Transient Synchronization Stability Analysis of Grid-forming Grid-connected Inverter Considering Damping Characteristics

构网型并网逆变器(GFM-GCI)可以为电网提供电压和频率支撑,有利于提高电网稳定性。首先,针对GFM-GCI的暂态同步稳定问题,在考虑阻尼特性的基础上采用等面积法则,从能量角度定性分析GFM-GCI控制参数对暂态同步稳定性的影响机理。然后,采用摄动理论中的多尺度法得到功角非线性二阶微分方程的显式解析解,定量分析控制参数对GFM-GCI暂态同步稳定性的影响。接着,基于解析解和暂态同步稳定边界,给出一种面向GFM-GCI暂态同步稳定的控制参数设计方法,所提控制参数设计方法与现有传统暂态分析方法相比,保守性更低。最后,通过仿真和实验验证了理论分析、解析模型与所提控制参数设计方法的有效性。

The grid-forming grid-connected inverter(GFM-GCI)can provide the voltage and frequency support for power grids,which is beneficial to grid stability improvement.Firstly,aiming at the transient synchronization stability problem of GFM-GCI,the influence mechanism of GFM-GCI control parameters on the transient synchronization stability is qualitatively analyzed from the perspective of energy by the equal area criterion considering the damping characteristics.Secondly,the explicit analytical solution of the nonlinear second-order differential equation of the power angle is obtained by using the multi-scale method in perturbation theory,and the influence of control parameters on the GFM-GCI transient synchronization stability is quantitatively analyzed.Then,based on the analytical solution and transient synchronization stability boundary,a control parameter design method for GFM-GCI transient synchronization stability is presented.The proposed control parameter design method is less conservative than the existing traditional transient analysis methods.Finally,the validity of the theoretical analysis,the analytical model and the proposed control parameters design method is verified by simulation and experiment.