A Wide-Bandwidth Grid Impedance Emulation for Compliance Testing of Grid-Connected Converters

This article proposes a flexible wide-bandwidth grid impedance emulation solution for weak grid compliance tests of grid-connected converters. With the presented strategy, the PCC voltage reference is dynamically shaped by utilizing the voltage reference and real-time PCC current. As a result, interactions between grid and converters are dynamically demonstrated in a wide frequency domain with a high precision. Therefore, the dynamic impacts of the grid impedance during interactions of grid and converters are clearly revealed. Finally, the propositions are verified on a lab-scaled grid emulator prototype.