The solar PV based power generation systems are growing faster due to the depletion of fossil fuels and environmental concerns. Combining PV panels and energy buffers such as battery through multi-port converter is one of the viable solutions to deal with the intermittency of PV power. The goal of this paper is to design and analyze the proposed triple port DC-DC buck-boost converter for high step-up/step-down applications. It has two unidirectional ports (port-1 and port-3) and one bi-directional port (port-2) for harnessing photovoltaic energy and charging the battery. At port-1, the combined structure of buck and buck-boost converter is used with a particular arrangement of switches and inductors. The step-up/step-down voltage conversion ratio is higher than the conventional buck-boost converter, and the polarity of the output voltage is maintained positive. The battery is added at the bi-directional port, for the storage of energy through the bi-directional boost converter. The switches operate synchronously for most of the modes making the control strategy simple. The characteristics and modes of operation along with a switching strategy, are elaborated. Experimental results are presented which validate the agreement with the developed theoretical expectation.

High voltage conversion dc/dc converters have perceived in various power electronics applications in recent times. In particular, the multi-port converter structures are the key solution in DC microgrid and electric vehicle applications. This paper focuses on a modified structure of non-isolated four-port (two input and two output ports) power electronic interfaces that can be utilized in electric vehicle (EV) applications. The main feature of this converter is its ability to accommodate energy resources with different voltage and current characteristics. The suggested topology can provide a buck and boost output simultaneously during its course of operation. The proposed four-port converter (FPC) is realized with reduced component count and simplified control strategy which makes the converter more reliable and cost-effective. Besides, this converter exhibits bidirectional power flow functionality making it suitable for charging the battery during regenerative braking of an electric vehicle. The steady-state and dynamic behavior of the converter are analyzed and a control scheme is presented to regulate the power flow between the diversified energy supplies. A small-signal model is extracted to design the proposed converter. The validity of the converter design and its performance behavior is verified using MATLAB simulation and experimental results under various operating states.

This manuscript focuses on a multi-port non-isolated (Dual input and single output) DC/DC power electronic interface based on Z-Quasi Resonant (ZQR) network. The converter accommodates grid and Photovoltaic panel (PV) as its input sources. Unlike the basic DC/DC converters, the recommended DC/DC converter requires fewer switches and provides continuous current, high gain in voltage, and minimal voltage stress on converter switch up to 40% duty cycle owing to the presence of ZQR network. This feature of the converter makes it to find its application in Electric Vehicle (EV) off-board charging where high voltage gain is required. In the proposed multi-port ZQR converter, additional input and output ports could be appended without compromising the converter’s gain and efficiency. The developed converter can operate continuously even if any one of the input sources fails to charge the EV. The proposed converter is mathematically modeled using basic laws that govern the converter performance and analyzed in MATLAB simulink platform under various operating modes. A detailed analysis under steady-state, dynamic conditions and a comparison of the developed multiport ZQR DC/DC converter with the topologies addressed in published literature are also presented in this manuscript. In order to verify the proposed converter performance, a prototype model of 300 W has been fabricated with switching frequency of 20 kHz. Experimental results confirm the effectiveness of the theoretical analysis, the aforementioned advantages, and features of the proposed multiport ZQR DC/DC converter.

A nonisolated three-port DC–DC converter based on Cuk topology (NI-TPC) to handle the renewable sources (RS) is proposed in this paper. This converter includes two unidirectional input ports accommodating both a fuel cell (FC) and photovoltaic (PV) cell; and one output port with DC load. Due to the inductors at all the ports, it claims the advantage of continuous input and output currents. Additionally, it uses less number of switches, diodes and inductors compared with conventional ‘n-1’ separate Cuk converters. Synthesis procedure for a generalized n-port DC–DC structure is explained. The derivation law based on conventional Cuk converter, operating principle, design calculation, and analysis are presented in detail, and then the analysis is validated through simulation and a 100W prototype, verifying the performance of the proposed NI-TPC converter.

An efficient way of synthesizing a three port non-isolated converter from a single-ended primary inductor converter (SEPIC) is proposed in this paper. The primary SEPIC converter is split into a source cell and a load cell. Two such source cells are integrated through direct current (DC) link capacitors with a common load cell to generate a three-port SEPIC converter. The derived converter features single-stage power conversion with reduced structural complexity and bidirectional power flow capability. For bidirectional power flow, it incorporates a battery along with an auxiliary photovoltaic source. Mathematical analyses were carried out to describe the operating principles and design considerations. Experiments were performed on an in-house-built prototype three-port unidirectional converter, and the results are presented to validate the feasibility of the designed converter.