Consensus enhanced droop control strategy for islanding mode multi converter system

Abstract

Under the gradual expansion of the new energy distributed generation, the islanding multi converter microgrid system plays a great role. The stability of voltage and frequency of multi converter systems in islanding mode and the coordination of power allocation among many converter systems have become vital research points. Focusing on the reactive power sharing problem of multi converter system for different line impedances and load disturbances, this paper proposes a consensus enhanced droop control strategy to achieve power sharing and voltage and frequency stability, and the mechanism and steady-state performance of the proposed control strategy are analyzed and studied. In this work, a multi converter system simulation model composed of six inverters is built in the software PLECS, which verifies that the consensus enhanced droop control scheme can make up for the shortcomings of the traditional droop control. Moreover, the hardware experimental setup of three-phase inverter system is further conducted to validate the simulation results. Under load disturbance, the control effects of consensus enhanced droop control proposed in this paper are analyzed and studied, and the good dynamic characteristics of consensus enhanced droop control strategy are verified. Finally, the high robustness of the proposed coordinated control strategy is further illustrated by the jump of unbalanced load. This paper clarifies the effectiveness of the proposed control strategy based on consensus algorithm in solving the reactive power sharing problem of different line impedances and load disturbances around the island mode multi converter system. Furthermore, the work in the paper can ensure effective reactive power sharing under various working conditions with high robustness.

Keywords

• Multi converter system
• Power sharing
• Consensus algorithm
• Enhanced droop control