直流微电网的储-荷虚拟直流电机优化控制技术

Optimal control technology of storage load virtual DC machine in DC microgrid

为提升虚拟直流电机(VDCM)控制对直流微电网的电压惯性与阻尼支持能力,并改善负荷侧的电压响应,提出了储-荷VDCM优化控制技术。通过类比直流电机的外特性建立储能侧和负荷侧VDCM动态模型。对VDCM控制进行改进,在储能侧对系统提供惯性支持,在负荷侧对系统施加阻尼控制,从而消除储能侧VDCM中电压惯性和阻尼的冲突,为系统母线提供足够的动态支撑。在此基础上,设计负荷侧惯性灵敏度控制环节,使储-荷VDCM能够为负荷提供灵活可控的电压惯性。根据李雅普诺夫稳定理论,分析所提VDCM优化控制对系统的稳定支持作用,根据分析提出参数优化方案,并利用时域仿真分析,验证所提控制策略的有效性。

In order to improve the voltage inertia and damping support ability of virtual direct current ma⁃chine(VDCM)control to DC microgrid and improve the voltage response at load side,an optimal control technology of storage load VDCM control is proposed.The VDCM dynamic models at energy storage side and load side are established by analogy with the external characteristics of DC machine.The proposed VDCM is improved to provide inertial support for the system at the energy storage side and damping con⁃trol at the load side,so as to eliminate the conflict between voltage inertia and damping in the VDCM at the energy storage side and provide sufficient dynamic support for the system bus.On this basis,the load side inertia sensitivity control link is designed,so that the storage load VDCM can provide flexible and controllable voltage inertia for the load.According to Lyapunov stability theory,the stability support effect of the proposed VDCM optimal control on the system is analyzed,the parameter optimization scheme is pro⁃posed according to the analysis,and the effectiveness of the proposed control strategy is verified by timedomain simulation analysis.