Optimized design of voltage control rules for distributed energy sources at substation inverter interfaces

Abstract Aiming at the voltage control problem of inverter-interfaced distributed energy resources in microgrid systems, this paper proposes an optimized design scheme based on coherent drafting control. The distributed energy is divided into multiple subsystems through cluster division to form a hierarchical control architecture. Within the cluster, a distributed optimization algorithm is used to achieve fast voltage convergence to the target value. Meanwhile, a coherent drafting control strategy is introduced to enhance the synergy between clusters and improve the overall stability of the system, and the optimization effect is evaluated using the voltage retention index (NVRI). The results show that the method can effectively maintain the system voltage stability under the situation of large fluctuations in distributed energy processing. In addition, the analysis of the two optimization cases of “minimum interaction with the grid and minimum operating cost” reveals that after the optimization of the system in this paper’s method, the power interaction with the grid is reduced by 3,168.542 KW, and the optimization performance is improved by 73.92%; the daily operating cost of the system after this paper’s method is significantly reduced under this condition (1229.47 yuan), and the economic efficiency is improved by 4.51%. It can be seen that the method of this paper improves the reliability and economy of the distributed energy system, proves the effectiveness of the control strategy of the method of this paper, and provides a new idea for the voltage control of distributed energy at the substation inverter interface.