Research of droop control strategy in DC distribution network

With the development of direct current (DC) distribution network, more attentions are paid to the influence of droop control strategy. Nonlinear droop control has unique advantage in the current sharing accuracy and bus voltage stability. As we know, during the operation of the DC system, the bus voltage should be stable, and the output of each power port should be reasonably distributed. However, the traditional droop control can increase the droop gains to improve the accuracy of current sharing, but at the same time, it will lead to a large bus voltage drop, which cannot meet the requirements of system in the current sharing and bus voltage adjustment rate. In this paper, related research is carried out to solve the system requirements of the above problems. First, this paper focuses on the mathematical control models of the linear. Next, analyses the advantages of nonlinear droop control. Then, this paper discusses the bus voltage drop in the load side and current sharing in the DC system. Final, this paper evaluates the line and converter loss in the efficiency of DC system and compares the different control strategies in the Matlab.