Converter-based PMSG emulator: A testbed for renewable energy experiments

This paper presents a converter-based permanent magnet synchronous generator emulator as a testbed for designing, analyzing, and testing of the generator drive and its control system as an actual device under test. The permanent magnet synchronous generator model is formulated in a real-time digital simulator. A voltage type ideal transformer model combined with a virtual impedance is presented as an interface algorithm. The design procedure and implementation of the virtual impedance in a simulation platform is discussed. A 6-switch converter as a power amplifier is used to mimic the behavior of the generator at the point of common coupling with an actual device under test. The accuracy and stability of the proposed emulator are investigated over a demanding frequency range. Technical challenges of the electrical generator emulator are considered, and proper solutions are suggested. Finally, the emulation is tested and verified through linear and nonlinear loads.