This paper is focused on the modeling and simulation of a hysteresis current-mode regulated high-gain DC–DC converter intended for solar applications. First, the study effort outlined the working ...principle of a novel high-gain DC–DC converter scheme called a double-switch SEPIC-buck converter (DSSB). This work also presents the dual hysteresis current control technique, which aims to enhance the system's performance and lower the harmonic content of its voltages and currents. Two dual hysteresis current controllers independently control the source and load currents of the proposed converter. The frequency and hysteresis bandwidth are also simultaneously set using the two controllers. Compared to other standard DC–DC converters (buck, SEPIC, boost, and buck-boost), DSSB has better efficiency, a larger voltage gain, and superior dynamic characteristics. The suggested topology has a peak efficiency of 95% and a voltage gain of 1+DD/1-D. The suggested DSSB converter has a THD of 6.6% and an efficiency of 97–98% when compared to various DC–DC converters, while the conventional SEPIC converter, along with boost, buck, and buck-boost converters, have a THD of 10% and an efficiency of 95–97%. Additionally, the DSSB converter has a far smaller crest factor than all other DC–DC converters, including boost, buck, buck-boost, and SEPIC. The suggested converter's performance is theoretically assessed using simulations based on Matlab/Simulink software under various circumstances. The results of simulation work in Matlab/Simulink corroborate the findings of the analysis and investigation.
In addition to their conventional use in electric motor drives, DC-DC converters have a variety of other uses, such as energy storage, energy conversion, cyber security systems, uninterruptible power ...supplies, and renewable energy systems. An innovative DC-DC converter is suggested in this article. Designing a new, high-gain DC-DC converter scheme known as a double-switch SEPIC-buck converter (DSSB) is possible after making some adjustments to the SEPIC converter that is currently known in accordance with accepted techniques. The output voltage magnitude of the proposed converter is either larger than or less than the input voltage magnitude and is the same sign as the input voltage. According to the theoretical and analytical study that has been supported by the real-world application, high voltage gain, low switching stress, and low inductor current ripple are the main characteristics of the proposed DSSB converter. The related small-signal model was also used to build the closed-loop system. The frequency response and output voltage behavior were investigated when the input source voltage abruptly changed as a step function. Based on the comparison study with other DC-DC converters, the DSSB converter outperforms currently known DC-DC converters such as Buck, SEPIC, Boost, Buck-Boost, and other SEPIC converter topologies in terms of voltage gain, harmonic content, normalized current ripple, dynamic performance, and efficiency. Additionally, the frequency response and control of the proposed converter using an alternate current (AC), small-signal, analysis-based, current-mode control technique are both provided. Thus, the DSSB is regarded as safe in overcurrent situations because of the small-signal analysis with the current control strategy. As a result of the verification of the proposed control technique, the resistance to changes in the DSSB parameters, improved dynamic performance, and higher control accuracy are further advantages of current-mode control based on small-signal analysis over other control approaches (PI controllers). Finally, the experimental and simulation results from Simplorer 7 and MATLAB/Simulink are used to validate the findings of the analytical and comparative investigation.
This paper considers the principles of modeling, control, and simulation of variable speed wind turbines (VSWTs), based on a stand-alone doubly fed induction generator (DFIG). The DFIG is used to ...feed a three-phase highly inductive load through a long cable via a three-phase multi-level frequency converter (MLFC). The proposed MLFC increases the number of voltage levels with less power electronic components as compared to the conventional back-to-back AC/DC/AC converter. The length of the cable (transmission line TL) influences a mismatch between the load and TL impedances; therefore, a reflected signal will occur. If the "incident signal" is a "continuous AC waveform", these waveforms will mix with another oncoming "incident waveform", creating stationery waveforms called "standing waves". The simulation process shows that the value of the transient’s over-voltage that appears either on the windings of the DFIG or across the load reaches twice the DC-link voltage periodically, which may cause premature failure of the DFIG windings and cable insulations. Usually, this is produced by generating high harmonics within the loads. Therefore, the main benefit of using the MLFC is the significant reduction of the total harmonic distortion and enhancement of the load voltage waveforms. This was verified, primarily by using the "MATLAB/Simulink, Simplorer 7" simulation software.
The use of renewable energy generation (REG) and energy storage systems (ESSs) strategies have a considerable possibility in delivering resilience for renewable energy sources (RESs). Thus, combining ...REG and ESSs strategies to fix operational, economic, ecological, and power-concerning governmental issues have been received particular concern from power system (PS) operators and planners globally. In this concern, developing countries (Jordan), which are poor in traditional energy resources, have proposed different supportive issues and experiences for the common use of ESSs strategies in the situation of distribution PSs. Therefore, this article performs a universal solution to this problem possessed to construct the infrastructure substantially to achieve high penetration of RE in the PS. Based on this, the article firstly studies the necessity of using REG and ESSs strategies in RE-based distribution PS. So, the current approaches and motivation programs used in various countries for the growth of RERs in optimum composition with ESSs and REG strategies are offered. The results of this study suggest that the use of an ESS is very important for the management and development of residential Solar Energy (SE) applications. Most respondents (85.3%) said that the use of a domestic ESS is critical to the management and growth of demand and supply for RE. To improve main grid efficiency and reduce demand for conventional power supplies, Jordanian engineers and experts recommend that consumers should install ES devices in their homes.
Nowadays, power plants, generators, substations, and equipment are becoming technologically more sophisticated and difficult to control besides that any interruption in power supply will cause losses ...to the industry and economy. Therefore, the importance of maintenance with enhancing availability, performance efficiency, on-time deliveries, safety necessities, and overall plant productivity become more necessary.
In this context, the electricity industry in Arab countries is increasingly realizing the importance of the maintenance role. The main objective of this paper is to assess the maintenance management (MM) practices, operational performance, and issues faced by maintenance functions in Jordanian power companies as a representative case study for all Arab countries.
A comprehensive survey methodology was developed, implemented, and presented to collect data in this study.
To achieve this goal, a questionnaire was developed to analyze the requirements, and service difficulties, namely, maintenance planning, automation implementation, maintenance barriers, productivity measurements, staff training needs, and assessment. We then distributed the questionnaire to a selected sample of Jordanian electricity companies which has been filled out mainly through text surveys and personal interviews.
The main obtained results of this study, related to maintenance practices and procedures that promote equipment availability, are summarized as increased use of predictive, intensive maintenance, computerized maintenance management systems (CMMS), and maintenance troubleshooting techniques. Additionally, more understanding of the company's development strategy and maintenance automation.
Thus, a more comprehensive maintenance program has to be implemented, so that the enhancement of performance in the equipment availability can be attained.
The main focus of this article is to analyze and simulate the two-leg parallel connection of a chopping up regulator with flattering inductive smoothers or with an interphasing centre-tap transformer ...supplied by a three-phase diode rectifier and a DC link in between. The article deals with the problem of reducing total harmonic distortion, minimizing THD and EMI with low switching frequency. The Simulated three phase a.c. load model is added at the end to investigate the current and voltage harmonics. The main objective of this paper is the investigation of the problem and active impact of replacing flattering inductive smoothers used to reduce voltcurrent fluctuating waveforms of the chopping up regulator by new topology known as interphasing centre-tap transformer with magnetic coupling. The comparison of these two variations of the study is then done based on their technical parameters and economical investment viewpoint. The considered technical parameters are to be current distribution into individual legs, amount of voltcurrent ripple and area of discontinuous currents. The investment costs governed by the material requirements are essential for transformer and smoother production design. The outcome of using the interphasing centre-tap transformer is successive cancelation of voltcurrent fluctuating waveforms generated at the output of the chopping up regulator. This is proved by an experiment with 35 in input and power chopping up400-V/90-A.Software simulations in Simplorer and Matlab/Simulink or software program and regimen prototypes have been arranged to confirm the results.
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