Self-adaptive inertia control of DC microgrid based on fast predictive converter regulation

To solve the problem of low inertia in DC microgrid and enable the distributed units to provide adaptive inertia support for the system under disturbance, this study proposes a novel adaptive inertia control strategy for DC microgrid combined with fast predictive converter control. In this strategy, adaptive coordinated inertia control of wind power system, AC power grid and energy storage system of the microgrid is designed according to the characteristics of corresponding micro-sources. Therefore, inertial response of the DC microgrid under disturbance is improved through the regulation of controllable inertia coefficient of each converter. In addition, to avoid control hysteresis and adjustment error, a fast converter local control method based on model predictive approach is proposed to cooperate with the rapid inertia adjustment strategy. To verify the effectiveness of the proposed adaptive inertia control method based on model predictive approach, contrastive simulations are conducted using the proposed control strategy and the traditional control strategy separately based on MATLAB/Simulink. The results show that the proposed control method can effectively improve the transient response to disturbance of the system and guarantee the stability of DC bus voltage as well as the output power quality on AC side of grid-connected converter.