Search results for "Verters"
showing 10 items of 163 documents
Comparative Analysis of Modified Modulation Scheme for Three-phase Voltage fed QZS Inverters
2019
Single-stage converters are one promising solution in different field of applications. In particular, quasi-Z-Source VSI topology structure playsan important role because it presents the same advantages of VSI and qZS converters. In addition, it allows increasing the inverter reliability. Moreover, modulation schemes and control strategy are still being developed. For this reason, aim of this paper is to introduce a modified modulation scheme based on the Maximum Constant Boost Control (MCBC) concept and Switching Frequency Optimal (SFO)as reference signals that represents the novelty issue of this work. The analysis has been carried out by comparing the performance of the converter in term…
A stacked interleaved DC-DC buck converter for proton exchange membrane electrolyzer applications: Design and experimental validation
2019
Abstract Since the two last decades, hydrogen production has been attracting the attention of the scientific community thanks to its inherent very low pollution when energy coming from renewable energy sources (RESs) are used. However, it implies the use of DC/DC converters to interface source and load. These conversion systems must meet several requirements from current ripple point of view, energy efficiency, and performance to preserve the sustainability of hydrogen production. This article proposes the design and realization of a stacked interleaved buck converter to supply a proton exchange membrane electrolyzer. The converter is designed to ensure a low output current ripple and a sui…
MATLAB Co-Simulation Tools for Power Supply Systems Design
2011
ion level. Circuit simulation software as Powersim PSIM and Orcad Pspice are the most common choice for circuit modelling. In (Basso, 2008), the design and simulation of switchmode power supplies is deeply analyzed and simulation tips in several environments are proposed. ASIC simulation and verification tools as Xilinx ISE/Modelsim or Aldec ActiveHDL are available to implement the digital controller by the VHDL or VERILOG source code. Since the interaction between subsystems is the most common source of faults, testing separately analog and digital subsystems by the means of different verification tools is a severe mistake. Matlab is a powerful simulation environment for mixed-mode systems…
Modified Modulation Techniques for Quasi-Z-Source Cascaded H-Bridge Inverters
2018
Quasi-Z-source cascaded H-bridge (q Z S - C H B) inverters are one promising solution for high power photovoltaic (PV) systems. This type of topologies inherits the advantages of cascaded converters (i.e., multilevel outputs) and impedance-source inverters (i.e., high conversion ratios). In addition, it allows increasing the inverter reliability (with high redundancy). However, the modulation and control of qZS-CHB inverters are challenging to a certain extent. Thus, this paper proposes modified modulation techniques to increase the performances of qZS-CHB converters in terms of voltage gains and stresses. The novelty lies in the use of the switching frequency optimal as reference signals i…
Experimental study on B-spline-based modulation schemes applied in multilevel inverters for electric drive applications
2019
This work presents the design, simulation, and experimental validation of new B-Spline-based modulation techniques applied to a Multilevel Power Inverter (MPI), particularly focusing the attention on the harmonic content of the output voltages of the inverter. Simulation and experimental results are proposed and discussed, mainly describing the potential benefits, such as the increase of the multi-level operation of the converter, and drawbacks (low-order harmonics) related to the adoption of B-Spline functions for multilevel inverters applied in the field of electrical drives.
Power System Oscillations with Different Prevalence of Grid-Following and Grid-Forming Converters
2022
The oscillatory behaviour of the power system is an aspect that is significantly affected by the increasing integration of converter-based generation sources. Several works address the impact of non-synchronous generation on the operation of the system from different points of view, but only a few studies focus on power-frequency oscillations with a prevalence of generation sources interfaced through power electronics. A lack of research can be found in particular in the comparative analysis of the two main control strategies for power converters, namely grid-following and grid-forming. The article aims to contribute to this direction, starting from a theoretical analysis of the two control…
Experimental Investigation on the Performances of a Multilevel Inverter Using a Field Programmable Gate Array-Based Control System
2019
The Field Programmable Gate Array (FPGA) represents a valid solution for the design of control systems for inverters adopted in many industry applications, because of both its high flexibility of use and its high-performance with respect to other types of digital controllers. In this context, this paper presents an experimental investigation on the harmonic content of the voltages produced by a three-phase, five level cascaded H-Bridge Multilevel inverter with an FPGA-based control board, aiming also to evaluate the performance of the FPGA through the implementation of the main common modulation techniques and the comparison between simulation and experimental results. The control algorithm…
Robust model-following control of parallel UPS single-phase inverters
2008
This paper presents a robust control technique applied to modular uninterruptible power-supply (UPS) inverters operating in parallel. When compared to conventional proportional-integral (PI) control, the proposed technique improves the response of the output voltage to load steps and to high distorted output currents, reducing the distortion of the output voltage. Furthermore, an excellent distribution of currents between modules is achieved, resulting in fine power equalization between the inverters on stream. The crossover frequency of the different loop gains involved is moderate, so that robustness to variations of the operation point and to modeling uncertainties is achieved. A compara…
Thermal Stability of a DC/DC Converter with Inductor in Partial Saturation
2021
Inductors operated in quasi saturation in dc–dc converters allow reduction of the core size and realization costs; on the other hand, they imply an increase of dissipated power that can jeopardize the thermal stability of the converter. In this article, this issue is studied by a mathematical model able to represent both the inductor nonlinearity and its temperature dependence. The main losses, such as ohmic, skin effect and magnetic, are taken into account in the model. The inductor is characterized by a polynomial curve whose parameters are a function of the temperature. Finally, the whole converter is modeled and simulation results, obtained on a boost converter, are compared with experi…
A comparison of different DC-DC converters for energy storage management in nearly-Zero Energy Buildings
2020
In the recent years, there has been a notable interest towards renewable sources, energy saving and efficiency optimization, in order to reduce the damages brought by fine dust and greenhouse gases in terms of safety, health and environmental protection. In the building sector renewable sources and energy efficiency optimization are leading to a large scale employment of nearly-Zero Energy Buildings (n-ZEBs), meaning that the balance between produced and required energy is negligible. For a proper n-ZEB implementation, a power system architecture has to be accurately designed, according to the existing renewable sources, loads and storage systems. In this paper, an investigation on differen…