Indirect Sliding Mode Power Control for Power Converter based Three-phase Load Emulator

摘要

This paper deals with an improved control of load emulator, indeed earlier researchers applied VOC to ensure current regulation or to generate the current profile of a specific load. This study investigates the indirect sliding mode power control for a converter based three phase load emulator. This load emulator is composed of a back-back converter and it is an indispensable tool in test benches which aim to evaluate equipment under test performances based on normative conformity under various load conditions. The proposed control is characterized by its robustness against external disturbances and parameters variations. In fact, the resonance of the LCL filter, used to connect the load emulator to either a grid or equipment under test, can modify the desired current profile. In addition, the large variation of the grid impedance (typically under weak grid conditions) can also change the desired behavior of the load emulator. The proposed control ensures that the load emulator draws the desired current profile even for large impedance variation and LCL filter resonance problem. Simulation and experimental results are presented and compared for the VOC and the indirect sliding mode power control in order to show the performances and robustness of the suggested control strategy.