Parallel kernel solver of an FPGA-based real-time simulator for active distribution networks

Field-programmable gate array (FPGA)-based real-time simulators are often applied in simulations of active distribution networks (ADNs) because of their parallel architectures and low cost. The overall performance of an FPGA-based real-time simulator is mainly determined by its kernel solver, which solves the nodal equation at each simulation time step. With the increasing scale of ADNs, real-time simulations of fast switching dynamics, along with limited computation hardware, have increased the requirements of the solver in terms of both time and resource consumption. In this study, a highly parallel kernel solver is proposed to improve the simulation efficiency of the FPGA-based real-time simulator. The multi-level parallel design and its implementation, including the parallelism at the system and module and element levels, are presented in detail. A modified IEEE 123-node system with distributed photovoltaics (PVs) is then simulated using a three-FPGA-based real-time simulator. Simulation results are compared with the commercial simulation tool PSCAD/EMTDC to validate the proposed kernel solver.