Coordinated control study of optical storage DC microgrid system

In pursuit of maximise the use of distributed renewable energy and to control loads with fluctuating demand better, an energy management and coordination policy is presented for a DC microgrid consisting of solar power generation, energy conservation system, resistive load and constant power load. Firstly, the paper pose the system construction and running mode of the DC microgrid; Secondly, different strategies are used to guarantee the stability of the system by controlling the converters in a coordinated manner, and the secondary control based on mixture compensation is utilized to achieve bus voltage reliability and load matching in the system in view of the problems of voltage drop and parallel current equalization in the traditional droop control; Finally, the fluctuation of output power of PV units and load variation occurring in the operation are investigated. Finally, the simulation of the output power fluctuation and load variation of the PV power generation unit is verified in MATLAB/Simulink. The results demonstrate that the proposed control policy can restrain the volatile DC bus voltage, reasonably distribute the power output of each generation unit. Besides, it can improve the reliability and stability of the system, and verify the effectiveness and feasibility of the control strategy.