Single Phase DC-DC Converters Research Articles

A new family of bidirectional DC-DC power converters with very low input and output ripples

Bidirectional DC-DC converters with very low ripple contents in the input and output sides are desirable in many applications. This paper proposes a new family of bidirectional DC-DC converters with very low input and output ripples that is derived from the conventional Cuk DC-DC converter. At first, a new family of single-phase DC-DC converter is derived. Then, extension of this family into the multiphase ones is presented. Output voltage expressions of the proposed DC-DC converters are presented. It is found that the derived DC-DC converters have lower conduction losses than the conventional DC-DC converters. Expressions of input and output ripples of the proposed DC-DC converters are then also presented. Finally, some experimental results are included to show the basic performance of the proposed converters. Thus, the outcome of the proposed DC-DC converter can be achieved by using the duty ratio is half and the multiphase technique is upper-middle inductors. It given that the current and voltage ripples of proposed DC-DC converter is very low and almost zero.

Three-Phase Three-Level Soft Switching Dc-Dc Converter for Industrial Applications

In high power DC applications, the single-phase DC-DC converter will face large voltage and current stress in each control switch and thereby the power handling capacity is less. To overcome this problem, three-phase DC-DC converter is used and it is suitable for high power applications with reduced number of switches as compared with the conventional topologies. The asymmetrical duty cycle control is considered to operate the switches under soft switching and hence the switching losses are reduced. The transformer leakage inductances are used along with junction capacitances in order to form resonance and hence ZVS commutation is possible in a wider load range. The modified phase shift control method is used for the proposed converter.The operational modes and design equations of the proposed converter have been observed. The simulation is carried out with a load of 1000W for validating the proposed work.

Implementation of Closed Loop Controlled PFC Bridgeless Cuk Converter Fed PMBLDC Motor in Mining Applications

Digital Simulation of a Power Factor Correction (PFC) bridgeless Cuk converter based adjustable speed controlled VSI fed PMBLDC motor is presented in this paper. A single-phase DC-DC converter topology based on the bridgeless Cuk converter is employed for PFC which ensures near unity power factor over wide speed range. The proposed speed control scheme has the concept of DC link voltage control proportional to the desired speed of the PMBLDC motor. The speed is regulated by a PI controller. The PFC converter based PMBLDCM drive is designed, modeled and simulated using MATLAB- SimuLink environment. Merits of the proposed power converter include unity power factor, less harmonic content, less switching loss, simpler control stage, higher power density and unidirectional power flow. This drive ensures high accuracy and robust operation from near zero to high speed.

A Novel Concept for Simplified Model of a Three-Phase AC-DC Converter Using PFC-Controlled Property

This study focused on three simplified models, namely (1) one set of single-phase DC-DC converter, (2) two sets of parallel connection single-phase DC-DC converter, and (3) two sets of series connection single-phase DC-DC converter. The purposes are: (1) to propose the simplification conditions and procedures for the three-phase AC-DC converter; (2) propose a set of new simplification steps for modeling, and present the examples of different three-phase AC-DC circuit topologies, detailed discussion on the simplification steps for modeling of a three-phase AC-DC converter is offered, to help people simplify and analyze the simplified model easily; (3) according to three types of simplified modeling in the three-phase AC-DC converter, this study established a useful reference for the design and analysis of the control systems of the three-phase AC-DC converter simply; (4) to acquire PWM control strategy beforehand based on PFC-Controlled property; (5) to reduce the switching loss for the PWM control strategy of the simplified model; (6) to maintain the original circuit topology and verify that the theory can extensively apply the knowledge of single-phase DC-DC converter to the simplified modeling of three-phase AC-DC converter.