A Novel SVM Strategy to Reduce Current Stress of 3-3 AC/AC HFLMC

3-3 ac/ac high-frequency link matrix converters (HFLMCs) with single-stage power conversion and bidirectional power flow are crucial for generating power from renewable energy sources or in isolated applications. However, conventional space vector modulation (SVM) strategies and control methods in a 3-3 ac/ac HFLMC produce high current stress in its high-frequency transformer (HFT) and excessive harmonics in the three-phase output current. This article proposes a bipolar SVM strategy that combines the modulation indices <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</i><sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> in the 3-1 MC, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</i><sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> in the 1-3 MC, and phase shift angle <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">φ</i>, analyzes the HFT’s current stress, and determines the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</i><sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub>, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</i><sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>, and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">φ</i> when the peak value of current stress is minimum. Simulation and experimental results show that the new SVM strategy reduces the HFT’s current stress, achieves a lower total harmonic distortion (THD) of the three-phase output current, and improves the efficiency.