改进VSG控制的储能系统并网优化策略

Grid connected optimal strategy of energy storage system based on improved VSG control

为解决新能源装机规模大幅提升带来的波动性和随机性对储能系统并网频率稳定性的影响,以及功角变化引起有功功率和无功功率的耦合从而造成功率振荡的问题,提出一种改进虚拟同步机(virtual synchronous generator,VSG)并网优化控制方法,通过在VSG有功-频率环节叠加功率前馈控制,在无功-电压环节加入功角变化对无功的补偿策略,并利用非线性变化惯性权重的改进粒子群(PSO)算法进行设计参数迭代求解,得到最佳控制参数优化并网性能。可解决功率波动对电网频率暂态性能的影响,改善大功角时无功功率的动态响应。在Matlab中建立VSG储能系统仿真验证并网性能优化,通过RT-LAB半实物仿真实验验证所提出改进VSG控制策略的可行性和有效性。

In order to solve the fluctuation and randomness of the grid connected frequency of the energy storage system caused by the sharp increase of the installed scale of new energy,the change of power angle has a great impact on the power coupling,resulting in power oscillation.An improved virtual synchronous generator(VSG)grid connection optimization control method is proposed.By superimposing power feedforward control on the active frequency link of VSG,adding the compensation strategy of reactive power angle change in the reactive power voltage link,and using the improved particle swarm optimization(PSO)algorithm with nonlinear inertia weight to iteratively solve the design parameters,the optimal control parameters are obtained to optimize the grid connection performance.The influence of power fluctuation on the frequency transient performance of power grid is solved,and the dynamic response of reactive power at large power angle is improved.VSG energy storage system is established in Matlab to simulate and verify the optimization of grid connection performance.Through RT-LAB hardware in the loop simulation experiment,the results show that the proposed improved control strategy is feasible and effective.