孤岛并联虚拟同步发电机暂态功率分配机理分析与优化控制

Analysis and Optimal Control of Transient Active Power Sharing between Islanded Parallel Virtual Synchronous Generators

虚拟同步发电机在孤岛并联时可以通过下垂控制实现稳态的有功功率均分。但是在线路阻抗、惯量、阻尼等参数不相等的情况下,负载变化时会产生有功功率的过冲和振荡。该文将负载变化的暂态过程分为两个阶段,并采用等效电路模型分析第一阶段特性,采用状态空间小信号模型分析第二阶段特性及参数影响。在此基础上,提出一种基于虚拟电感和暂态阻尼的暂态主动功率分配的优化方法,从而在不影响稳态功率分配的前提下改进了暂态有功分配的性能。最后,基于Matlab/Simulink的仿真以及实验结果验证了所提方法的有效性。

Virtual synchronous generator control can realize the active power sharing between parallel inverters in steady state.However,the difference of inertia,damping or line impedance may cause active power overshoot and oscillation.In this paper,the active power transient process during load transition is divided into two stages.The characteristics of the two stages are analyzed by the equivalent circuit model and the small signal model model respectively.On this basis,the transient active power sharing optimization method based on virtual impedance and transient damping is proposed.Finally,the Matlab/Simulink simulation and experimental results validate the availability of the proposed method.