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This work focuses on a new non‐isolated interleaved DC‐DC converter with very high step‐down voltage conversion ratio. By employing the switched/series capacitor concept, along with the proper component interconnection, the converter features a high step‐down voltage conversion ratio where, in the private case of equal duty ratios, it is six times higher than the conventional buck converter. This high step‐down voltage conversion ratio is achieved with the lowest number of components compared to other similar topologies of the same conversion ratio. Also, due to the blocking/series capacitors, the voltage stress on the switches is reduced, improving the converter efficiency. One of the key features of the proposed converter is the inherent automatic current sharing between the interleaved phases, which in the case of equal duty ratios, is uniformly distributed. To add on, due to the use of only two interleaved phases, the converter has a wide output voltage range, since the duty cycle can be extended to 0.5. To validate the proposed converter operation, a 250 W wide‐input/wide‐output experimental prototype was built, achieving a peak efficiency of 94%. [ABSTRACT FROM AUTHOR]

The prescribed perspective of high accession of distributed generation photovoltaic (DG‐PV) units on low‐voltage distribution networks has brought up many issues regarding their performance in case of network transient phenomena. In this study, the design principles that DG‐PV units must incorporate in order to meet the requirements of low‐voltage ride through capability (LVRTC) are investigated through detailed theoretical analysis and calculations. The analysis shows that a realistic over‐sizing of interfaced inverters of DG‐PV as well as an appropriate selection of the equivalent interconnecting reactance XDG, in conjunction with high penetration levels, can lead to satisfaction of LVRTC demands without violating the protection limits of the network. Moreover, the scenario of uniform dispersion along the distribution lines is proved rather favourable concerning the demand of LVRTC for voltage selectivity. Finally, considering the derived outcomes, a methodology of optimum design about LVRTC is proposed within the framework of reasonable constraints, which can be applied to any low‐voltage distribution network. [ABSTRACT FROM AUTHOR]