S. Thangaprakash, A. Krishnan,
Volume 6, Issue 2 (6-2010)
Abstract
New control circuits and algorithms are frequently proposed to control the
impedance (Z) source inverter in efficient way with added benefits. As a result, several
modified control techniques have been proposed in recent years. Although these techniques
are clearly superior to the simple boost control method which was initially proposed along
with the Z-source inverter (ZSI), little or conflicting data is available about their merits
relating to each other. In this paper, it is shown how the shoot-through periods are inserted
in the switching waveforms of the power switches and the performances of them are
analyzed based on the operation of ZSI. Simple boost control, maximum boost control,
constant boost control and space vector modulation based control methods given in the
literature has been illustrated with their control characteristics. A critical investigation on
ripples of the impedance source elements, output voltage controllability, output harmonic
profile, transient response of the voltage across the impedance source capacitor and voltage
stress ratio etc has been presented with the simulation results. The simulation results are
experimentally verified in the laboratory with digital signal processors (DSP). DSP coding
for the above all control techniques has been generated by interfacing Matlab/Simulink
with DSP C6000 tool box and signal processing block set.
E. Babaei, H. Feyzi, R. Gholizadeh-Roshanagh,
Volume 13, Issue 4 (12-2017)
Abstract
In this paper, a generalized buck-boost Z-H converter based on switched inductors is proposed. This structure consists of a set of series connected switched-inductor cells. The voltage conversion ratio of the proposed structure is adjusted by changing the number of cells and the duty cycle. Like the conventional Z-H converter, the shoot-through switching state and the diode before LC network are eliminated. The proposed converter can provide high voltage gain in low duty cycles. Considering different values for duty cycle, the proposed structure works in two operating zones. In the first operating zone, it works as a buck-boost converter and in the second operating zone, it works as a boost converter. In this paper, a complete analysis of the proposed converter is presented. In order to confirm the accuracy of mathematic calculations, the simulations results by using PSCAD/EMTDC software are given.
H. Shayeghi, S. Pourjafar, F. Sedaghati,
Volume 17, Issue 2 (6-2021)
Abstract
This work introduces a new non-isolated buck-boost DC-DC converter. Interleaved configuration of the suggested structure increases the voltage conversion ratio. The voltage rate of the suggested converter can be stepped-up and stepped down for lower values of duty-cycle, which causes to decrease in the conduction losses of the system. The voltage conversion ratio of the recommended structure is provided with low maximum voltage throughout the semiconductor elements. Additionally, utilizing only one power switch facilitates converter control. Using a single power MOSFET with small conducting resistance, RDS-ON, increases the overall efficiency of the recommended topology. To verify the performance of the presented converter, technical description, mathematical survey, and comparison investigation with similar structures are provided in the literature. Finally, a laboratory scheme with a 100W load power rate at 50 kHz switching frequency is carried out to demonstrate the effectiveness of the proposed converter.
