Hardware-in-the-Loop (HIL) simulation is a critical technique for validating embedded controllers in power-electronic systems such as electric vehicles and data centers, where switching frequencies can exceed 100kHz. Achieving real-time performance at these frequencies requires sub-microsecond simulation steps while maintaining sufficient numerical accuracy. Existing commercial HIL solutions predominantly rely on FPGA platforms due to their fine-grained timing control and deterministic execution. However, the emergence of spatial, dataflow-oriented accelerators raises the question of whether alternative architectures can meet these stringent requirements.

High-efficiency energy conversion systems have become increasingly important due to their wide use in all electronic systems such as data centers, smart mobile devices, E-vehicles, medical instruments, and so forth. Complex and interdependent parameters make optimal designs of power converters challenging to get. Recent research has shown that machine learning (ML) algorithms, such as reinforcement learning (RL), show great promise in design of such converter circuits. A trained RL agent can search for optimal design parameters for power conversion circuit topologies under targeted application requirements. Training an RL agent requires numerous circuit simulations. It requires significantly more training iterations when the tolerance of circuit components due to manufacturing inconsistency, aging, and temperature variation is considered. As a result, they may take days to complete, primarily because of the slow time-domain circuit simulation. This paper proposes a new FPGA architecture that accelerates the circuit simulation and hence substantially speeds up the RL-based design method for power converters. Our new architecture supports all power electronic circuit converters and their variations. It substantially improves the training speed of RL-based design methods. High-level synthesis (HLS) was used to build the accelerator on Amazon Web Service (AWS) F1 instance. An AWS virtual PC hosts the training algorithm. The host interacts with the FPGA accelerator by updating the circuit parameters, initiating simulation, and collecting the simulation results during training iterations. A script was created on the host side to facilitate this design method to convert a netlist containing circuit topology and parameters into core matrices in the FPGA accelerator. Experimental results showed$\mathbf{60}\times$overall speedup of our RL-based design method in comparison with using a popular commercial simulator, PowerSim.

High-efficiency energy conversion systems have become increasingly important due to their wide use in all electronic systems such as data centers, smart mobile devices, E-vehicles, medical instruments, and so forth. Complex and interdependent parameters make optimal designs of power converters challenging to get. Recent research has shown that reinforcement learning (RL) shows great promise in the design of such converter circuits. A trained RL agent can search for optimal design parameters for power conversion circuit topologies under targeted application requirements. Training an RL agent requires numerous circuit simulations. As a result, they may take days to complete, primarily because of the slow time-domain circuit simulation.