Title |
Circulating Current Reduction Method Using High Frequency Voltage Compensation in Asynchronous Carriers for Modular Scalable Inverter System |
Authors |
Seung-Yeon Choi ; Shin-Won Kang ; Jun-Hyuk Im ; Rae-Young Kim |
DOI |
https://doi.org/10.6113/TKPE/2018.24.2.71 |
Keywords |
Circulating current ; IPMSM(Interior Permanent Magnet Synchronous Motor) ; MSIS(Modular Scalable Inverter System) ; Voltage compensation |
Abstract |
This study proposes a circulating current reduction method that uses high-frequency voltage compensation when carrier phase difference occurs between two inverters in MSIS. In MSIS, inverters are configured in parallel to increase power capacity and to increase efficiency by using inverters only as needed. However, in the parallel inverter structure, circulating current is inevitably generated. Circulating current increases the stress on the switch, adversely affects the current control performance, and renders load sharing difficult. The proposed method compensates for the output voltage reference of the slave module by using the high-frequency voltage so that the switching pattern of each module is matched even in asynchronous carriers. The validity of the proposed method is verified by simulations and experiments with 600 W IPMSM. |