| Title |
A Carrier-Shifting Strategy for Zero-Sequence Circulating Current Reduction in Grid-Connected Parallel Inverters |
| Authors |
Seong-Eun Lee ; Younghoon Cho |
| DOI |
https://doi.org/10.6113/TKPE.2026.31.4.281 |
| ISSN |
1229-2214(pISSN), 2288-6281(eISSN) |
| Keywords |
Parallel inverter; Circulating current; Carrier phase shift |
| Abstract |
This study proposes a new pulse-width modulation (PWM) method that reduces high-frequency zero-sequence circulating current (ZSCC) in parallel three-phase inverter systems by applying carrier-phase inversion. The proposed single-phase inversion PWM inverts the carrier phase of only one phase by 180° while maintaining the conventional 180° interleaving between inverters. This method selectively shifts the common-mode voltage (CMV) generation timing of each inverter, thereby reducing the CMV difference that directly drives high-frequency ZSCC. The operating principle of the proposed method is analytically verified using a double Fourier integral-based frequency-domain model, and its effectiveness is demonstrated through PSIM simulations and experimental results. |