基于功率动态区域划分的自适应虚拟同步发电机控制策略OA

With the increasing proportion of renewable energy in the grid,the overall damping and inertia of the grid decline,which brings challenges to the safe and stable operation of the grid.Virtual synchronous generator(VSG)technology,by simulating the characteristics of synchronous generator,brings damping and inertia support to the grid.However,it inevitably brings problems such as active low-frequency oscillation and active steady-state deviation.Through the establishment of VSG model,the oscillation mechanism of VSG is analyzed.The small-signal model of active power reveals the principle of low-frequency oscillation and steady-state deviation of active power caused by moment of inertia and damping coefficient.In order to suppress the low-frequency oscillation of active power and eliminate the steady-state deviation of active power,an adaptive VSG control strategy based on power dynamic region division is proposed.According to the different power change rates,the system is divided into the acceleration region and the deceleration region,so as to adaptive control the rate of increase or decrease of the moment of inertia and the damping coefficient,so that VSG has good dynamic characteristics in different working modes.The proposed strategy can effectively suppress the active low-frequency oscillation of VSG,reduce the steady-state deviation of the active power,and improve the active power support capability of VSG.Finally,the system simulation model is built in MATLAB/Simulink,and the correctness of the proposed strategy is verified.