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In this paper, eight ultrahigh-voltage gain dc–dc converters are proposed. These sets of converters are derived by the association of boost cells, coupled inductor, voltage multiplier, switched capacitors, and LC filter cells. The nonpulsating input and output converters are evaluated in terms of: principle of operation, voltage gain, voltage and current stress, estimated power losses, and efficiency. Following full analysis prototypes built in the laboratory show experimental results verifying the theoretical analysis. [ABSTRACT FROM AUTHOR]

This paper proposes a new grid current controller for a photovoltaic (PV) module integrated buck inverter using a single pulsewidth modulation switch and an unfolding H-bridge, which significantly reduces switching losses. To achieve this, an internal grid current loop with active damping is presented with an LCL filter to connect it to the utility grid. The problem of the filter natural resonance is solved by means of a virtual impedance (active damping), demanding no additional sensor. Experimental results obtained from a 200-W prototype achieved a European efficiency of 96.27% with a current total harmonic distortion of 3.7%. [ABSTRACT FROM AUTHOR]

High step-up converters are required for distributed photovoltaic generation systems, due to the low voltage of the photovoltaic source. In this paper, a new hybrid high voltage gain dc–dc converter is created by merging the standard boost converter with a coupled inductor and different switched-capacitor techniques. With a single switch and no requirement of higher duty cycle values, the proposed converter achieves a high voltage gain and high efficiency, in addition to lowered voltage and current stresses of the components. A 200-W prototype was implemented experimentally to evaluate the converter, which reached a maximum efficiency of 97.6%. [ABSTRACT FROM AUTHOR]

A synthesis methodology for developing a set of very high step-up dc–dc converters is presented and discussed in this paper. The proposed method makes use of a boost converter as basic topology in which three step-up techniques are combined and incorporated. The studied techniques are the switched capacitors voltage multipliers (VM), the diode VMs, and the coupled-inductors. With the proposed methodology, many well-known converters are identified and two novel converters are proposed. In addition to a detailed analysis of the synthesis of each topology, a comparative analysis among of some important converters is presented. This comparison involves aspects such as voltage gain, voltage stress, component stress factor, component count, and relative cost. By means of these comparisons, the main characteristics and constraints of the analyzed converters are identified. Results from 250 W prototypes, designed according to photovoltaic ac-module specifications, are obtained experimentally to validate the theoretical analyses and point out advantages and limitations of each converter. The results demonstrate that the combination of the three studied techniques provides the best trend off on the comparative analysis carried out in this work. [ABSTRACT FROM PUBLISHER]

This paper presents a comparative evaluation of eight high-voltage step-up converters based on different associations of boost and zeta standard dc–dc pulse width modulation (PWM) cells. These eight converters present different characteristics such as cascaded and stacked PWM cell associations, as well as isolated winding coupled inductors, tapped winding coupled inductors, and noncoupled inductors. In order to explore the advantages and address the limitations of each topology, several comparative evaluations concerning static voltage gain, power losses, current and voltage stresses, component stress factors, power density, relative cost, and efficiency were carried out. From the theoretical analysis and experimental results, the association named stacked boost–zeta with autotransformer yielded the highest efficiency and power density and resulted in the most attractive converter for the case study. [ABSTRACT FROM PUBLISHER]

This paper proposes a novel single-switch dc/dc converter for the future renewable electric energy delivery and management system to implement the distributed renewable energy resources (DRER). The DRER is responsible for the maximum power point tracking of the photovoltaic panel (PV) module and also for the control of central energy storage device. Due to the characteristics of the PV module and the dc-bus, the single power stage must provide low current ripple in the input and output terminals, must operate with output current and voltage regulation, and present a high-voltage conversion ratio. To achieve such features, this paper proposes a novel integrated Boost–Zeta converter. To avoid a complex modeling and control, we propose a disaggregation concept for this. Experimental results are presented for the purpose of operating the converter and also for the operation of the system. [ABSTRACT FROM PUBLISHER]