基于VSG的改进型虚拟阻尼控制策略与特性分析

传统虚拟同步发电机（VSG）控制策略可模拟同步发电机的惯量和阻尼特性，但会使并网逆变器产生功率振荡和功率偏差。针对虚拟同步发电机动态过程中存在的功率振荡问题，提出一种基于VSG的改进型虚拟阻尼控制策略来抑制功率振荡。首先介绍了传统阻尼绕组与常系数虚拟阻尼绕组抑制功率振荡的原理及特性，其次利用根轨迹法分析设计了改进型虚拟阻尼控制策略的参数，最后搭建仿真模型验证了该控制的有效性及准确性。

VSG based Improved Virtual Damping Control Strategy and Characteristics Analysis

The control strategy of traditional virtual synchronous generators （VSG）can simulate the inertia and damping characteristics of synchronous generators， but will cause power oscillation and power deviation of grid-connected inverters. Considering the power oscillation in VSG dynamic process，an improved virtual damping control strategy based on VSG is proposed to suppress the power oscillation. Firstly， the principle and characteristics of traditional damping windings and constant coefficient virtual damping windings to suppress power oscillation are introduced. Secondly，the root trajectory method is used to analyze and design the parameters of the improved virtual damping control strategy. Finally，the control effectiveness and accuracy are verified by building a simulation model.