Real-Time Simulation of Multi-Unit Power Conversion Systems for Enhanced Battery Energy Storage Development

Real-time simulation and hardware-in-the-loop (HIL) testing are essential tools for advancing the integration of Battery Energy Storage Systems (BESS) into modern power grids. As BESS applications grow in complexity and scale, especially with the increasing use of modular and high-frequency switching power converters, accurate and time-efficient simulation becomes a critical requirement for development and validation. This paper presents a scalable real-time benchmark model designed for large-scale BESS systems based on T-Type multi-unit power conversion systems (PCS). The model is implemented using a Field Programmable Gate Array (FPGA)-based solver capable of sub-microsecond time steps, enabling high-fidelity simulation of fast switching events and dynamic behavior. To accommodate the computational demands of large converter arrays, the model is distributed across multiple FPGA boards interconnected via high-speed optical fiber links. This setup allows for the real-time simulation of up to 240 power semiconductor switches operating at switching frequencies in the tens of kilohertz. Validation is performed using an offline reference model developed in MATLAB Simulink Power Systems. The results confirm the accuracy and scalability of the proposed benchmark, demonstrating its ability to support complex system architecture while maintaining real-time performance. This framework provides a flexible and efficient platform for testing and validating PCS designs and control strategies, helping to address key challenges in the deployment of BESS in renewable energy and smart grid applications.