An iterative real-time nonlinear electromagnetic transient solver on FPGA

Real-time transient simulation of nonlinear elements in transmission networks requires significant computational power. This paper proposes an iterative nonlinear transient solver on a field programmable gate array (FPGA). The parallel solver, based on the compensation method and the Newton-Raphson algorithm (continuous and piece-wise), is entirely implemented in VHDL. It also involves sparsity techniques, deeply pipelined arithmetic floating-point processing, and parallel Gauss-Jordan elimination. To validate the new solver, two case studies are simulated in real-time: surge arrester transients in a series compensated line and ferroresonance transients in a transformer, with time-steps of 5μs and 3μs respectively. The captured real-time oscilloscope results demonstrate high accuracy of the simulator in comparison to the off-line simulation of the original system in the ATP version of EMTP.