A Modified Multi-Winding DC–DC Flyback Converter for Photovoltaic Applications

Abstract

DC–DC power converters have generated much interest, as they can be used in a wide range of applications. In micro-inverter applications, flyback topologies are a relevant research topic due to their efficiency and simplicity. On the other hand, solar photovoltaic (PV) systems are one of the fastest growing and most promising renewable energy sources in the world. A power electronic converter (either DC/DC or DC/AC) is needed to interface the PV array with the load/grid. In this paper, a modified interleaved-type step-up DC–DC flyback converter is presented for a PV application. The topology is based on a multi-winding flyback converter with N parallel connected inputs and a single output. Each input is supplied by an independent PV module, and a maximum power point tracking algorithm is implemented in each module to maximize solar energy harvesting. A single flyback transformer is used, and it manages only 1/N of the converter rated power, reducing the size of the magnetic core compared to other similar topologies. The design of the magnetic core is also presented in this work. Moreover, the proposed converter includes active snubber networks to increase the efficiency, consisting of a capacitor connected in series with a power switch, to protect the main switches from damaging dv/dt when returning part of the commutation energy back to the source. In this work, the operating principle of the topology is fully described on a mathematical basis, and an efficiency analysis is also included. The converter is simulated and experimentally validated with a 1 kW prototype considering three PV panels. The experimental results are in agreement with the simulations, verifying the feasibility of the proposal.

An Overview of Non-Isolated Hybrid Switched-Capacitor Step-Up DC–DC Converters

“…Let us consider the case in which both capacitors have the same capacitance (C 1 = C 2 = C in ( 5)). The final stored energy would be expressed as (6).…”

“…Climate-change-related problems have focused the attention on renewable energy sources as an option to fossil fuels for electric energy generation [1][2][3][4][5][6][7][8]. Photovoltaic (PV) panels and fuel cells (FC) stacks are among the most studied renewable energy sources, but they produce electrical energy at a relatively low voltage; their voltage levels need to be boosted before being injected into the utility grid.…”

A Novel Feedback Linearisation Control of Flyback Converter

“…Currently, the improvement of the power electronic equipment has led to momentous growth in many industrial segments, such as e-mobility or renewable energy (Pesce et al, 2021;Ramos-Paja et al, 2021;Tseng and Fan, 2021). A common feature of the above industrial segments is that the auxiliary circuits of the equipment require a stable direct current (DC) voltage, which is achieved by a DC/DC or alternating current (AC)/DC converter.…”