A novel control strategy in low-voltage DC microgrid

With the increase of the load and the growth of length of the line, it is not available to get the voltage rating by the conventional droop control. As a result, an improved control strategy based on dynamic virtual resistance is proposed in low-voltage DC microgrids. The designed dynamic virtual resistance is changed with the load current and the drop of voltage amplitude. The value of virtual resistance is adjusted adaptively and constantly under the work of the dynamic virtual resistance loop, so that the problem of virtual resistance value setting can be solved. At the same time, the voltage drop is reduced, circulating current is inhibited and the system power quality is improved effectively, while the system stability performance is satisfied. Simulation results verify the feasibility and effectiveness of the proposed control strategy.