Mounir Bouzguenda, Tarek Selmi, Adel Gastli and Ahmed Masmoudi
The purpose of this paper is to study the problem of the leakage currents in transformerless inverter topologies. It proposes a novel topology and how important the adopted…
Abstract
Purpose
The purpose of this paper is to study the problem of the leakage currents in transformerless inverter topologies. It proposes a novel topology and how important the adopted control strategy on the power quality produced by the inverter.
Design/methodology/approach
The paper presents an investigation of a novel transformerless inverter topology. It adopted a control strategy in which the DC source is disconnected from the inverter when the zero vectors of the control are applied. By using such control strategy, the electrical efficiency of the whole system was improved and the leakage current was significantly reduced.
Findings
The paper provides a solution to minimize the leakage current in transformerless inverter topologies. Besides, the problem of zero-crossing distortions was totally eliminated.
Research limitations/implications
Because of the high conversion ratio of the boost converter, the efficiency of the whole system needs to be enhanced.
Practical implications
The paper includes the experimental results of the proposed topology which are in good match with the simulation results.
Originality/value
This paper identifies a need to study the leakage current phenomena in transformerless inverter topologies.
Details
Keywords
Ahmed Khadhraoui and Cherif Adnen
The purpose of this study is to present a new approach of a hydrogen-based green energy supply system intended for powering electric vehicles using fuel cells (FCs) and suitable…
Abstract
Purpose
The purpose of this study is to present a new approach of a hydrogen-based green energy supply system intended for powering electric vehicles using fuel cells (FCs) and suitable for sustainable urban automobile transportations.
Design/methodology/approach
To resolve the problems with current electric vehicles, which are cost, autonomy and charging infrastructure, the authors have developed in this study a new prototype which uses an autonomous hydrogen production system, embedded in the vehicle and assisted by a photovoltaic source and ion-lithium batteries. The on-board produced hydrogen is then used by a reversible FC (PEMFC) to generate electricity to power the vehicle engine.
Findings
The obtained results demonstrated that the FC could provide approximately 70% of the required current once the vehicle was in motion, with the remaining 30% supplied by the battery. The carbon dioxide (CO2) emissions were reduced of 98%.
Research limitations/implications
A most vehicles use an internal combustion engine causing serious air pollution and the inability to meet new clean energy standards with zero CO2 emissions. In this same context, hybrid vehicles produce at least 80 g of CO2 every km, which is much higher than the Kyoto, Copenhagen and Paris COP21 policies.
Social implications
This study will help to create the best ecological ecosystem with low greenhouse emissions.
Originality/value
This concept offers many advantages, such as increased range, reduced recharge time, increasing the system autonomy and no CO2 emissions, which contribute to reducing air pollution, regulation with CE protocols and moving toward cleaner and more sustainable mobility.
Details
Keywords
This paper aims to examine why the alliance formed between non-Islamist forces and state actors to oust Mohamed Morsi from power in 2013 broke down quickly.
Abstract
Purpose
This paper aims to examine why the alliance formed between non-Islamist forces and state actors to oust Mohamed Morsi from power in 2013 broke down quickly.
Design/methodology/approach
This paper makes use of original data set derived from three waves of surveys fielded in 2011, 2014 and 2015 that ask questions about public threat perception. Around 10 elite interviews were also conducted to further test the study’s hypothesis.
Findings
On the one hand, non-Islamists, civic forces challenged the status and interests of state actors in a way that made state actors view them with heightened distrust. On the other, many civic forces, in face of high threat perception, prioritized law during and order after Morsi’s removal, driven – at least partly – by shifts in public attitudes.
Originality/value
Many views look at transitions in the Arab world from the angle of how Islamists interact with traditional power holders. Such an approach, however, could be reductionist in many ways because it disregards civic forces. This is a point this paper seeks to address.