Abstract:
In order to improve the inertia and transient performance of power electronic conversion devices connected to traditional new energy and energy storage, and realize stronger adaptability of control strategy,a hierarchical coordination adaptive virtual machine control strategy is proposed. The power angle curve and angular frequency oscillation curve are analyzed on the AC side,and the adaptive parameters of the the virtually synchronous machine(VSM) are designed based on the power deviation. The adaptive link of virtual DC machine(VDCM) is designed based on the bus voltage deviation. The inertia essence of energy storage body and converter is analyzed to limit the inertia amplitude. The control effect is verified by simulation. Compared with the traditional micro grid energy storage control strategy, the amplitude of frequency drop is reduced by 0.025 Hz, the amplitude drop of bus voltage is reduced by 1.2 V, and the dynamic response time is shortened by 0.2 s, it further reduces the fluctuation amplitude,shortens the time to reach stability, and has stronger adaptability to frequent load fluctuations.