考虑储能SOC限制的光储VSG自适应控制策略

Adaptive Control of PV Storage Strategy VSG Considering Storage SOC Limitations

针对光伏微电网频率波动大、稳定性差的问题,设计了一种基于虚拟同步发电机(VSG)控制的光伏混合储能系统协调频率控制策略。首先,利用混合储能功率分配控制策略平抑光伏出力波动;其次根据VSG的虚拟惯量和阻尼系数灵活可控和储能侧蓄电池不能过充过放的特点,提出了一种考虑储能荷电状态(SOC)限制的改进虚拟惯量和阻尼系数自适应控制策略;最后分别通过Matlab/Simulink仿真和半实物仿真实验对所提策略进行了验证。仿真和实验结果表明该策略可提高系统频率响应和功率响应速度,加快系统频率恢复,同时减少储能充放电次数、延长其使用寿命。

Aiming at the problems of high frequency fluctuation and poor stability of photovoltaic microgrid,a coordinated frequency control strategy of photovoltaic hybrid energy storage system based on virtual synchronous generator(VSG)control is designed.Firstly,the hybrid energy storage power distribution control strategy is used to smooth out the fluctuation of photovoltaic output.Secondly,according to the characteristic that virtual inertia and damping coefficient of vSG are flexible and controllable and the battery cannot be overcharged or overdischarged,an improved virtual inertia and damping coefficient adaptive control strategy considering the limitations of the state of charge(SOC)of the energy storage is presented.Finally,the proposed strategy is verified by Matlab/Simulink simulation and semiphysical simulation experiments.Simulation and experimental results show that this strategy can improve the frequency response and power response speed of the system,accelerate the frequency recovery of the system,reduce the number of charge and discharge times of the energy storage,and extend its service life.