Parallel connection of two or even more single-phase inverter modules is a successful solution to increase the reliability and the efficiency of an inverter at moderate power levels. Stable operation and proper current sharing among parallel inverter modules is a key issue, especially when they are connected to a common load through unequal output filter impedances. In this paper, a new formulation and consequently a proper current sharing control algorithm for parallel connected inverter modules with the possibility of unequal filter impedances is proposed. Also a dual-loop voltage control with the filter current as the inner loop feedback signal, considering the effect of digital control delay, is adopted. The controller parameters are designed according to a frequency domain analysis. Finally, theoretical achievements are confirmed by experimental test results on a test rig with two 250 W parallel connected single phase inverters.
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Sarvghadi, P., & Monfared, M. (2022). Stable Operation and Current Sharing Control among Parallel Single-Phase Inverter Modules with Unequal Filter Impedances. Journal of Operation and Automation in Power Engineering, 10(2), 134-142. doi: 10.22098/joape.2022.9668.1673
MLA
P. Sarvghadi; M. Monfared. "Stable Operation and Current Sharing Control among Parallel Single-Phase Inverter Modules with Unequal Filter Impedances". Journal of Operation and Automation in Power Engineering, 10, 2, 2022, 134-142. doi: 10.22098/joape.2022.9668.1673
HARVARD
Sarvghadi, P., Monfared, M. (2022). 'Stable Operation and Current Sharing Control among Parallel Single-Phase Inverter Modules with Unequal Filter Impedances', Journal of Operation and Automation in Power Engineering, 10(2), pp. 134-142. doi: 10.22098/joape.2022.9668.1673
VANCOUVER
Sarvghadi, P., Monfared, M. Stable Operation and Current Sharing Control among Parallel Single-Phase Inverter Modules with Unequal Filter Impedances. Journal of Operation and Automation in Power Engineering, 2022; 10(2): 134-142. doi: 10.22098/joape.2022.9668.1673