This paper presents a new high step-up DC-DC switched-mode converter in which not only the Input and output ports can be connected to a common ground, but also the service time of the Input source is extended due to Continuous Current injection to the proposed power converter. Furthermore, the fast dynamic response is offered by minimum phase characteristics. This key feature is achieved by making the proposed converter’s control to output transfer function, free from the right half plane zero (RHPZ). Full description of the operation principles, theoretical analysis related to steady-state operation, and also the small-signal modelling derivation of the proposed converter, are presented in this paper. In the end, to confirm all the merits of the proposed converter and accuracy of theoretical analysis, a sample 25 V - 100 V laboratory prototype DC-DC converter with 100W output power has been implemented, and the main experimental results have also been outlined.

In this paper, a single switch transformer-less DC-DC converter with Continuous Input Current for photovoltaic applications is proposed. The suggested configuration utilizes a CL1C2D2 structure to achieve a high voltage gain and alleviate voltage pressure on the semiconductor components. This design enables a significant increase in voltage output with a minimal turns ratio, leading to reduced size, weight, and cost of the converter system. The reduction in turns ratio of the coupled inductor results in lowered voltage stress on the semiconductor elements. Additionally, employing just one power switch in the converter simplifies control and reduces expenses. With its Continuous Input Current, this converter is particularly well-suited for integration in photovoltaic systems. Simulation results conducted using PSCAD/EMTDC software validate the efficacy of the proposed power converter. Furthermore, the maximum power output of the photovoltaic module through an MPPT (Maximum Power Point Tracking) controller under varying irradiance levels is determined, and simulations are executed using PSCAD/EMTDC.

The objective of this paper is to propose, study and analyze a non-isolated high step-up SEPIC-based DC-DC converter for photovoltaic applications. The proposed structure is based on the SEPIC converter and utilizes a two-winding coupled inductor along with an improved voltage multiplier cell in order to enhance the output voltage level. Moreover, a passive voltage clamp is used to reduce the voltage stress on the main switch and recover the energy stored in the leakage inductance of the coupled inductor. Hence, an active switch with low RDS-ON could be employed. Meanwhile, due to soft switching condition at turn-off instant of diodes, their reverse-recovery problems are solved. Furthermore, the presented converter has the merits such as Continuous Input Current, high efficiency and low cost and size which make it a promising solution for photovoltaic applications. At the end, the converter is compared to different types of DC-DC converters to show its advantages over the converters designed before. In order to verify the performance of the converter, a 200-W laboratory prototype is implemented and experimental results are taken and depicted. Results prove the feasibility and functionality of the presented converter for photovoltaic systems.

In this paper, an improved structure for two-stage inverters is proposed, which profits from high voltage boosting ability without using a transformer. The proposed structure consists of two main stages, including an improved dc-dc converter and an H-bridge. Using only one switch in the Input section (the proposed dc-dc converter), not only reduces the cost and dimensions of the converter, but also minimizes the number of working modes (only two modes) and, as a result, simplifies its control. The presence of a common ground point in the Input section is a feature that can eliminate the leakage Current caused by solar cells in photovoltaic applications. Due to the continuity of the Input Current and the ability to increase the voltage in the proposed structure, it will be possible to track the maximum power point in the application of solar cells. It will be possible to control the effective value of the output voltage of the proposed structure by controlling the duty cycle of the switch of the Input section. In this article, the proposed structure is introduced and additional explanations about its different operational modes are provided along with calculations related to loss and efficiency analysis. Also, a comparison between the proposed structure and a number of existing structures is presented. To prove the correct operation of the proposed converter as well as the correctness of theoretical calculations, simulation results extracted from PSCAD/EMTDC software are presented.

In this paper, a new high step-up Current-fed LLC resonant DC-DC converter with a center-tapped transformer is proposed. By selecting the switching frequency to be lower than, but near to, the series resonant frequency of the LLC resonant tank, soft-switching operation of all semiconductors, i.e., zero voltage switching (ZVS) turn-on of power MOSFETs and zero Current switching (ZCS) turn-off of diodes is achieved. This leads to lower electromagnetic interference (EMI) and lower switching losses and improves the converter efficiency. An interleaved structure is used at the primary side. Thus, Input Current ripple is smaller, and its frequency is twice the switching frequency. Consequently, a smaller Input filter is necessary in practice. The converter with 1.2 kW output power and 760 V regulated output voltage with 80-200 V Input voltage variations is simulated. The output voltage is regulated by using asymmetric pulse width modulation (APWM) at 200 kHz switching frequency. Finally, a 700-W prototype has been implemented and experimental results are also presented to verify the simulation results.

This paper investigates a fundamental issue in AC-DC rectifiers that are specifically used as charger for electric vehicle (EV), i. e. the total harmonic distortion (THD) of Input Current waveforms. Firstly, the topology of two-stage charger along with the corresponding control scheme is reviewed. Then, the research gap namely high harmonic distortion of Input Current is identified and analyzed. A revision of the conventional control method with the aid of virtual resistant is proposed and investigated from the circuit perspectives. Finally, simulation results are delivered to validate the analysis and the reduction of THD in the Input Current waveform. this is proposed method, the steady state is studied.