Abstract:
In complex multi-microgrids containing electric and hydrogen energy storage systems, there are different sizes and types of micro-sources, which makes it difficult to distribute the common load reasonably and further leads to the instability of the AC bus voltage frequency. In this paper, an adaptive control method for power distribution in the isolated complex multi-microgrids based on the equivalent hydrogen consumption is proposed. To uniformly evaluate the load margins of different microgrids, different micro sources within the microgrid are evaluated by the equivalent hydrogen consumption. In addition, the primary frequency modulation (FM) allocation coefficients of the multiple Virtual Synchronous Generators (VSG) are adaptively changed according to the dynamic characteristics and operating mechanisms of the actual micro sources, achieving a reasonable allocation of the common load in the real time by the distributed control. Next, the VSG adaptive control method proposed in this paper makes the rotational inertia and the damping coefficient adaptively controlled by identifying how fast the frequency changes, realizing the reduction of the frequency fluctuation overshoot while improving the response speed of the system. Finally, semi-physical experiments are carried out to verify the effectiveness of the proposed method.