In this study, a new interleaved full soft switching DC-DC boost converter with a high power reliability is proposed. To achieve soft switching, a simple auxiliary circuit consisting of one switch, one diode, one inductor and two capacitors is employed in each single-phase DC-DC boost converter connected in parallel. All switches and diodes, including main and auxiliary ones, operate under soft switching conditions. These soft switching conditions consist of zero voltage and zero current switching (ZVZCS) for all switches and diodes at switching transitions except the output diodes, which turn off only with zero current switching. The soft switching technique used in this study decreases power losses which leads the converter to have higher efficiency and reliability. Also, the auxiliary circuit is located out of the main power path preventing high voltage and current stresses on the switches. In this study, operational modes analysis, design procedure, power reliability evaluations and laboratory prototype results with switching frequency of 20 kHz, input voltage of 48 V and output power of 40 W are presented. T R component temperature rise above T AO R sng , R int single-phase and interleaved converters power reliabilities, respectively

In this study, a new circuit for cascade multilevel converter based on series connection of extended submultilevel units is described. In order to produce all levels at output voltage waveform, an algorithm is proposed to determine the values of dc sources. To maximise the number of output voltage levels with minimum number of utilised power electronic components, the proposed cascade multilevel converter is optimised. The comparison results with other recently presented topologies are provided in terms of the number of utilised components and standing voltage on switches. Compared to other structures, the proposed topology utilises fewer number of insulated-gate bipolar transistors, drivers, anti-parallel diodes, and dc sources. Also, the value of standing voltage of switches in the recommended topology is low. Experimental results for proposed converter are provided to verify the operation of presented structure.

No abstract

This paper presents a new switched-ladder structure for multilevel converter which consists of several bidirectional and unidirectional switches along with DC voltage sources. The values of DC sources in the proposed topology are determined based on a new mathematical algorithm. The proposed multilevel converter is an extended structure, which can produce any levels at output voltage waveform. To prove the merits of the proposed structure, the proposed converter is compared with other similar structures. According to comparison results, it is shown that the presented structure requires the least numbers of DC sources, IGBTs, drivers and on-state switches. Also, the value of voltage rating of the switches is analyzed. The experimental results are provided for the proposed 17-level converter to prove the performance of suggested structure.

No abstract