Research on stability control of AC/DC hybrid micro-grid based on multi agent system

Based on the operation characteristics of AC/DC hybrid micro-grid, this paper proposes a control strategy with multi agent system technique to realize the stability control of AC/DC hybrid micro-grid. It builds the simulation framework and multi agent framework of the hybrid micro-grid, including AC micro-grid agent, DC micro-grid agent and distribution grid agent. Aiming at the bidirectional AC/DC converter that keeps the power balance of the AC/DC hybrid micro-grid and ensures the operation stability of the microgrid, this paper firstly builds the mathematical model of bidirectional AC/DC converter, and then investigates the control strategies in different operation modes of the bidirectional AC/DC converter. By detecting the instantaneous frequency value of AC micro-grid and the instantaneous voltage value of the DC bus, the working modes of bidirectional AC/DC converter can be decided by the strategy, which consist of rectifier mode, inverter mode and stop mode. The simulation for the proposed strategy for the example system was applied on grid-connecting and islanding modes respectively with MATLAB/Simulink. The result shows that the stability control of the hybrid micro-grid can be achieved by the proposed control strategy with the multi agent system.