Consensus-based secondary control for DC microgrids with communication delays via a networked predictive control...

Area of Science:

• Electrical Engineering
• Control Systems
• Renewable Energy Systems

Background:

• Cyber-physical microgrids commonly use consensus-based secondary control for voltage and current regulation.
• Sparse communication networks in microgrids introduce unavoidable time delays, challenging control system performance.
• Existing methods often passively tolerate time delays, limiting system responsiveness and stability.

Purpose of the Study:

• To propose a novel networked predictive control (NPC) strategy for islanded DC microgrids.
• To actively compensate for communication time delays, rather than passively tolerating them.
• To ensure stable voltage regulation and proportional current sharing in the presence of time delays.

Main Methods:

• Developed predictive models for voltage and current based on the cyber-physical microgrid model.
• Implemented the NPC strategy to estimate real-time system states and actively counteract delay effects.
• Analyzed system stability using Schur stability criteria for the closed-loop system.

Main Results:

• The proposed NPC strategy effectively compensates for communication time delays in islanded DC microgrids.
• Experimental validation on a 48-V DC microgrid demonstrated the method's feasibility, delay tolerance, and robustness.
• Simultaneous achievement of voltage regulation and proportional current sharing was confirmed.

Conclusions:

• The networked predictive control strategy offers a superior approach to managing time delays in microgrid control.
• The method enhances the reliability and performance of islanded DC microgrids under communication constraints.
• NPC provides a robust and effective solution for advanced microgrid secondary control.