Real-Time Co-Simulation for DC Microgrid Energy Management with Communication Delays

TL;DR

This work addresses validating EMS for DC microgrids under realistic communication delays. It introduces a real-time CPS testbed consisting of a DC microgrid modeled in OPAL-RT, an EMS implemented on a Raspberry Pi using a rolling 24-hour receding-horizon optimization updated every five minutes, and a network emulator EXataCPS to inject latency via Modbus/TCP, enabling co-simulation of power, control, and communications. The key contributions include an integrated platform for co-validating control and network performance and a QoS-aware analysis showing how high-priority EMS data remains responsive while lower-priority traffic can degrade under congestion. Results demonstrate that the EMS can minimize grid energy costs while maintaining SoC and voltage within safe bounds, but unprioritized traffic can degrade performance under congestion, underscoring the need for QoS enforcement. Overall, the framework provides a practical route toward deployable, delay-tolerant EMS for delay-prone DC microgrids and sets the stage for future cybersecurity and adaptive-control enhancements.

Abstract

The growing integration of renewable energy sources (RESs) in modern power systems has intensified the need for resilient and efficient microgrid solutions. DC microgrids have gained prominence due to their reduced conversion losses, simplified interfacing with DC-based RESs, and improved reliability. To manage the inherent variability of RESs and ensure stable operation, energy management systems (EMS) have become essential. While various EMS algorithms have been proposed and validated using real-time simulation platforms, most assume ideal communication conditions or rely on simplified network models, overlooking the impact of realistic communication delays on EMS performance. This paper presents a novel real-time cyber-physical system (CPS) testbed for evaluating EMS performance in DC microgrids under realistic communication delays. The proposed testbed integrates a DC microgrid modeled in OPAL-RT with an EMS controller implemented on a Raspberry Pi (RPi). The communication network is emulated using EXataCPS, enabling the exchange of actual power system traffic and the replication of realistic latency conditions. This comprehensive setup captures the interplay between power system dynamics, EMS control, and communication network behavior.

Figures (10)

• Figure 1: Overview of the real-time CPS testbed architecture.
• Figure 2: Layout of DC microgrid.
• Figure 3: Cyber-physical setup integrating power system and communication network simulation.
• Figure 4: Lab setup of the CPS testbed.
• Figure 5: Power output of PV plants in DC microgrid.