基于无源性的直流微网虚拟惯性研究

Study on Virtual Inertia of DC Microgrid Based on Passivity

为提高直流微网中变换器的动态性能和直流母线电压的稳定性,文中提出一种基于无源性的虚拟惯性控制策略。首先基于变换器的端口受控耗散哈密顿模型,设计出无源电流控制器,然后引入虚拟直流电机控制作为电压外环。仿真结果表明,文中所提基于无源性的虚拟惯性控制策略可较好地提高直流微网的惯性;同时相比传统的下垂控制策略,当微网系统受到扰动时,变换器的动态性能和直流母线电压的稳定性有所提高,从而证明文中所提控制策略的可行性。

In order to improve dynamic performance of the converters and the stability of dc bus voltage in DC microgrid, a virtual inertia control strategy based on passivity is proposed. First, based on the port controlled Hamiltonian with dissipation model of the converters, passivity based on current controllers are designed, and then virtual DC machine control is introduced as the voltage outer loop. The simulation results show that the virtual inertia control strategy based on passivity proposed in this paper can better improve the inertia of the DC microgrid. At the same time, compared with the traditional droop control strategy, when the microgrid system is disturbed, the dynamic performance of the converters and the stability of the dc bus voltage are improved, which proves the feasibility of the control strategy proposed in this paper.