AC-Sweep Analysis and Verification of an AC Power Source with Virtual Output Impedance for Validation of Grid Connected Components

Abstract:
Modern grid connected power electronics (PE) technology more and more relies on both, high sophisticated testing and validation equipment and methods in order to pre-address severe impact of specific PE solutions on the local grid before going online. The most efficient and promising testing environment in terms of power density, results in an implemented switched-mode power amplifier which is capable of emulating output impedances like RL-components over a wide frequency range instead of coming up with real bulky passive components. Such AC power source technology has been introduced recently. The main objective of such specific test equipment is the integration of a proper control scheme for applied virtual grid impedance emulation. Thus, an AC-sweep analysis, regarding a performed offline simulation supported by experimental results might become handy in order to proof validity of the proposed concept. Hence, this paper is focused on an at least 2 kHz bandwidth AC-simulator hardware and software characterization, based on a comparison between a prepared offline simulation (PLECs), hardware-in-the-loop simulation (C-HIL, Typhoon HIL) and measurement results of an implemented 3 kW/200 kHz laboratory prototype.