Power Constrained Control of Average Consensus Method for Secondary Frequency Regulation in Islanded Microgrid

The average consensus method has been widely used in distributed secondary frequency control of islanded microgrid. However, this method cannot limit the output power of distributed generator (DG) within a safe range. To solve this issue, we first analyzed the saturator-based control and found that the combination of saturator and consensus protocol will cause a conflict between frequency recovery and the power sharing. Subsequently, a power limit constraint controller composed of a saturator and a logic judgment module is proposed in this paper. By adding the logic judgment in front of the average consensus protocol, the conflict is completely resolved. In addition, the cooperation between the proposed controller and the average consensus protocol enables frequency recovery, power sharing and power constraint objectives to be effectively achieved. Finally, the performance of the proposed control method is verified by a 5-node simulation model in MATLAB/SimPowerSystems.