A Power Converter Based Real-time Air-conditioner Motor Emulator

The residential air-conditioner (A/C) is one of the most widespread load types for a household in the U.S., and it is reported that the malfunction of A/C load influences the performance of the transmission network. However, the lack of accurate modeling of A/C loads limits the effectiveness of evaluating power system dynamic performance and grid stability analysis. A real-time power emulator for an A/C motor using a three-phase voltage source inverter (VSI) is proposed in this paper, which emphasizes the "point-on-wave" characteristics of the A/C load. The proposed VSI based A/C emulator is advantageous since it demonstrates an accurate dynamic performance without sacrificing the computational resources and simulation time. The experimental results verify the accuracy of the A/C load emulator. Furthermore, the fault-induced delayed voltage recovery (FIDVR) events are emulated and analyzed in a multiconverter based hardware test bed (HTB) by using the proposed A/C load emulator. In addition, experiments emulating the dynamic response of the A/C load driven by the power electronics (PE) interface is also performed in the HTB, verifying that the application of PE-interface-driven A/C motor can contribute to alleviating the FIDVR event.