SPWM-Based Direct Digital Control With Average-Voltage Model and D-Σ Process for Paralleled 3φ3W Grid-Connected Converters to Reduce Circulating Currents. - Tsai-Fu Wu; Ling-Chia Yu; Yen-Hsiang Huang; Ying-Yi Jhang; Bo-Tang Zeng (IEEE Trans. Ind. Electron., 2019)