Edge-Driven Distributed Control for Power Distribution: A Real-Time Hardware-in-The-Loop Testbed for Industrial Automation and Applications

Increasing integration of inverter-based distributed energy resource (DER) requires advanced control architectures beyond traditional grid systems control that were designed for simpler, slower grid. Among these advanced controls, distributed control offers a promising solution, but its performance can be strongly affected by real-world communication delays and hardware limitations. Validating these algorithms require a testbed that can simulate practical operational scenarios, including communication delays, hardware latencies, and system dynamics. We address this need by developing a real-time hardware-in-the-loop (HIL) testbed with edge-based distributed control and intelligence. Our approach couples feeder-scale power-flow simulation with microsecond-resolution inverter emulation and a number of Raspberry Pi controllers acting as distributed agents. The controllers exchange Message Queuing Telemetry Transport (MQTT) messages to implement a distributed Volt–VAR algorithm considering the inverter's DC-link and IEEE 1547 industry standards, with lock-step synchronization to capture true communication, computation, and actuation effects. The testbed is designed to implement a distributed voltage control algorithm using edge devices by integrating the control and actuation across four distinct layers. These layers include the physical electric grid (modeled in OpenDSS), the power electronic converters (emulated in Typhoon HIL), the communication network (managed via MQTT), and the distributed computing agents (implemented on Raspberry Pi hardware). By coupling these components into a real-time hardware setup, the architecture reveals complex cyber-physical interactions overlooked by software-only studies, validating the algorithm's performance under realistic industrial conditions.