FPGA-Based Custom Hardware-in-the-Loop Emulation of High-Power Induction Motor Drives with Sub-Microsecond Resolution Using NI LabVIEW FPGA

This paper presents the development and experimental validation of a custom Field-Programmable Gate Array (FPGA)-based hardware-in-the-loop (HIL) emulator for high-power induction motor drives. The proposed system enables real-time emulation of a variable-frequency drive consisting of a diode rectifier, a two-level voltage source inverter (VSI), and a 215 HP induction machine. The emulator is implemented on an NI PCIe-7857R FPGA platform using LabVIEW FPGA and fixed-point arithmetic optimised for Kintex-7 resources. A key contribution of this work is the achievement of a 100 ns real-time simulation time step for the converter and machine models, enabling accurate representation of fast switching dynamics while avoiding aliasing effects typically encountered in HIL systems. A multi-rate architecture is adopted to allocate appropriate sampling frequencies to different subsystems, improving computational efficiency and stability. Experimental results obtained from a closed-loop setup with an sbRIO-based controller demonstrate accurate emulation of inverter operation, induction machine dynamics, and controller interactions. The developed platform also enables detailed investigation of switching phenomena, such as voltage spikes, dead-time effects, and current ripple. Comparative validation with a Typhoon HIL 602+ platform confirms similar dynamic behaviour and harmonic performance, demonstrating that the proposed low-cost FPGA-based solution provides a flexible and high-fidelity alternative for real-time power electronics research and controller development.