Dynamic Variable Time-Stepping Schemes for Real-Time FPGA-Based Nonlinear Electromagnetic Transient Emulation

• Published in: IEEE transactions on industrial electronics (1982) Vol. 64; no. 5; pp. 4006 - 4016
• Main Authors: Zhuoxuan Shen, Dinavahi, Venkata
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.05.2017; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Case studies; Computational modeling; Field programmable gate arrays; Field-programmable gate array (FPGA); Hardware; high-level synthesis (HLS); Integrated circuit modeling; iterative scheme; nonlinear element; Nonlinear systems; parallel processing; power system simulation; Real time; real-time system; Real-time systems; Simulation; Simulators; Software development tools; surge arrestor; Surges; Transient analysis; variable time stepping
• ISSN: 0278-0046; 1557-9948
• DOI: 10.1109/TIE.2017.2652403

Electromagnetic transient (EMT) simulation of nonlinear elements in power systems is a particular challenge due to the requirements of an accurate representation and an efficient solution. The existing real-time simulators utilize a piecewise linear representation along with a fixed time step for the solution of nonlinear elements. This paper proposes the detailed methodologies for applying variable time stepping to real-time EMT simulation to improve the simulation accuracy and efficiency. The challenges, the feasible solutions, and corresponding restrictions of applying various variable time-stepping schemes along with nonlinear element solution methods in real time are discussed. The offline simulation and the real-time hardware emulation of two case studies, a full-bridge diode circuit and a power transmission system, are presented. The case studies were implemented on the field-programmable gate array device (Xilinx Virtex-7 XC7VX485T) in real time using high-level synthesis tool to achieve a parallelized and pipelined hardware design with minimum coding effort. The real-time emulation results captured by an oscilloscope are validated against the offline simulation on Saber and PSCAD/EMTDC software tools.