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Abstract This research paper presents a high-gain DC–DC converter with ultra-step-up voltage gain capability. The proposed converter is synthesized from a two-phase interleaved boost converter (IBC), and its voltage gain is doubled by adopting a voltage lift capacitor. To enhance its voltage gain capability, a floating capacitor-based gain extension cell is adopted subsequently. This cell yields a voltage gain that is cubed times the output voltage obtained from a classical boost converter (CBC). By cascading the two stages, the voltage gain of the proposed converter is enhanced to quartic times (4th power) that of the CBC. The proposed gain extension concept is validated by conducting practical experiments on a 16 V to 400 V, 150 W prototype version. Practically, the prototype converter delivers 150 W to the load and operates at a full-load efficiency of 92.7% when its switches are operated at safe duty ratio values. Under dynamic conditions, the proposed converter regulates the output voltage to 400 V quickly over a wide range of input voltage and load current variations; the overshoots and undershoots are also negligible. The maximum voltage gain of the proposed converter momentarily increases to 37 when the input voltage is drastically reduced to 10.8 V while the switches are still operated at safe duty ratio values. The voltage stress on the semiconductor devices is only a fraction of the output voltage due to the hybrid voltage gain extension technique. The input current is also ripple-free as the switches in the IBC structure are always operated at a duty ratio of 50%, and only the third switch is controlled to meet the required voltage gain. The salient features of the proposed converter are clearly highlighted by comparing it with several converters that possess quadratic, cubic, and quartic voltage gain functions. The common-ground connection between the source and the load in the proposed converter is an added preferable feature for PV applications.

This paper presents a high-gain DC-DC converter for photovoltaic (PV) applications. The proposed high gain DC-DC converter employs two coupled inductors, a voltage-lift capacitor, and two diode-capacitor multiplier cells to achieve a voltage gain of 21.11. The novel hybrid gain extension mechanism was validated by testing a 300 W prototype converter. During experimentation, it yielded an output of 380 V from an 18 V DC input and switched at 50 kHz. Because the switches in the interleaved stage are operated at a duty ratio of 0.5, the input current is ripple-free, and the switch current rating is also reduced. Owing to the location, the voltage stress on the switches was only 10.5% of the output voltage. Due to the adopted gain extension mechanisms, the voltage stress on the diodes was also reduced. The output voltage of the proposed converter is regulated by implementing a closed-loop control. In practice, the converter exhibits a good dynamic response when the line voltage and load current are subjected to step changes. The availability of a common-ground point is an additional advantage. Furthermore, the significant features of the proposed converter were validated by comparing its key parameters with many state-of-the-art converters available in the literature.

This paper proposes a single-phase, transformer-less, seven-level inverter that utilizes eight switches, three capacitors, and two diodes to produce seven voltage levels with triple boosting ability. The availability of the common-ground point eliminates the leakage current in PV applications. The proposed Transformer-Less Triple-Boosting Seven-Level Inverter (TLTB7LI) has the ability to feed different types of loads from non-unity to unity power factors. The voltage balancing of capacitors takes place naturally without the need for auxiliary circuits and complicated control strategies. This paper investigates the appropriateness of the proposed TLTB7LI for grid-connected application. The Peak Current Controller (PCC) is employed to generate the switching pulses and regulate the active/reactive power transfer between the converter and the output, which guarantees the high quality of injected current to the output. Moreover, the operational principles, its control technique, as well as the design procedure of the key components of the proposed inverter have been presented. The superiority of the proposed inverter over existing counterparts has been verified through comparative analysis. The simulation and experimental analysis validated the proper operation of the proposed TLTB7LI.

Abstract This paper proposes a novel single‐phase switched‐capacitor‐based inverter configuration that in its basic form can generate an 11‐level staircase output voltage waveform with sinusoidal output current for Resistive‐Inductive (R‐L) loads. The increased levels, quintuple voltage‐boosting factor, and natural voltage‐balancing of capacitors are considered the main features of the proposed basic configuration. The proposed topology requires fewer components (resources, switches, driver circuits, and capacitors) than recently presented similar structures to acquire the same voltage gain and output steps. The proposed basic configuration can be extended in two ways: increasing levels and/or boosting factors with minimal devices. The employment of two half‐bridges (rather than an H‐bridge) for generating bipolar waveform has limited the number of switches tolerating the maximum output voltage to 2 (instead of 4), which results in reduced total blocking voltage (TBV) and accordingly reduced cost and losses. A comprehensive comparative analysis has been done and presented to verify the supremacy of the suggested structure. The experimental results of the laboratory‐scaled prototype of the proposed basic topology have been provided, which approve its correct performance.

This paper suggests a single-input switched-capacitor Nine-level inverter configuration advantaging from quadruple voltage-boosting ability, natural voltage balancing of capacitors, and reduced components per level. Also, the single-source character of the proposed topology makes it cheaper and more compact. The cascaded version of the suggested topology has also been introduced, by which high boosting factors, as well as large number of steps, can be obtained. The proposed topology can effectively supply the resistive-inductive or pure inductive load types. The capacitors’ impulsive-charging-current issue has been solved by simple small-inductance-based inductor-diode (L-D) networks. The comparative analysis affirms the fewer device-usage in suggested configuration per equal gain or level count than existed structures, resulting in less size and cost. The usage of Nearest-Level modulation guarantees the low-frequency operation of semiconductors and reduces the switching losses. The comparative analysis and experimental outcomes affirm the competitiveness and accurate functionality of suggested configuration.