Hye-Won Choi and Kyo-Beum Lee, "Circulating Current Reduction for Parallel-Connected Modular Inverters Based on Suppression of Common-Mode Voltage," IEEE Transactions on Power Electronics, vol. 38, no. 9, pp. 11091-11101, Sep. 2023. -SCI > Paper

This paper presents a reduction method of circulating current (CC) for parallel-connected modular inverters based on suppression of

the common mode voltage. Parallel modular inverters have been widely utilized owing to their high-power output and convenience

for system design. However, the modular inverter cannot be manufactured as perfectly identical systems, and this facilitates the CC

in the system and decreases the reliability of inverters. There are several reduction methods for the CC, such as adding transformers

to cut open the current path and a controller to reduce the harmonics. These previous methods increased the size and weight of the

modular inverters and were affected by components of inverters such as inductance, resistance, etc. This study proposed a reduction

method of the CC using integrated modulation methods. The modulation is divided into two regions according to the magnitude of

voltage vectors. The proposed modulation is compared with the conventional space vector modulation to verify its effectiveness and

performance. Various simulations and experimental results verified the proposed method.