Lei Zhang¹, Yinlong Yuan^1,*, Yihe Sun², Yun Cheng¹, Dian Wu¹, Lei Ren¹

Energy Engineering, Vol.119, No.1, pp. 387-405, 2022, DOI:10.32604/EE.2022.017463

Abstract With the aggravation of energy problems, the development and utilization of new energy has become the focus of all countries. As an effective new energy, the fuel cell has attracted the attention of scholars. However, due to the particularity of proton exchange membrane fuel cell (PEMFC), the performance of traditional PI controlled phase-shifted full-bridge power electronics DC-DC converter cannot meet the needs of practical application. In order to further improve the dynamic performance of the converter, this paper first introduces several main topologies of the current mainstream front-end DC-DC converter, and analyzes their performance in the fuel cell system. Then,… More >

Hasan Alrajhi^*

Computer Systems Science and Engineering, Vol.41, No.2, pp. 717-734, 2022, DOI:10.32604/csse.2022.021279

Abstract The high potentiality of integrating renewable energies, such as photovoltaic, into a modern electrical microgrid system, using DC-to-DC converters, raises some issues associated with controller loop design and system stability. The generalized state space average model (GSSAM) concept was consequently introduced to design a DC-to-DC converter controller in order to evaluate DC-to-DC converter performance and to conduct stability studies. This paper presents a GSSAM for parallel DC-to-DC converters, namely: buck, boost, and buck-boost converters. The rationale of this study is that modern electrical systems, such as DC networks, hybrid microgrids, and electric ships, are formed by parallel DC-to-DC converters with… More >

K. Karthick^1,*, K. Jaiganesh², S. Kavaskar³

Energy Engineering, Vol.118, No.6, pp. 1887-1904, 2021, DOI:10.32604/EE.2021.017563

Abstract The energy efficient product can be operated with longer duration. They offer wonderful solutions compared to other conventional water pumping system as it needs less maintenance, simple in installation, zero fuel cost, longer operating life, highly reliable and free from production of greenhouse gases. In this paper we analyzed the different topologies of DC–DC converter in terms of their operating region of MPPT, quality of input and output currents. We discussed the MPPT algorithms to address partial shading effects in SPV array, present state of the technology, factors affecting the performance of the system, efficiency improvements and identified the research… More >

M. Usman Khan^1,*, K. M. Hasan¹, A. Faisal Murtaza², H. M. Usman², Hadeed A. Sher³

CMC-Computers, Materials & Continua, Vol.70, No.1, pp. 135-150, 2022, DOI:10.32604/cmc.2022.019381

Abstract

In this paper, a stand-alone photovoltaic (PV) system based on a Double Ended Forward Converter (DEFC) is presented. The proposed converter is specified for 48 V, 100 W applications as most of the equipment used in telecommunication and aircraft fall in this range. The literature has limited potential application of DEFC in PV systems. The research work deals with an in-depth study of DEFC and proposes an improved DEFC for PV applications with battery backup. Besides, a bi-directional dc-dc converter for the battery is integrated to track the Maximum Power Point (MPP) of the PV generator. The converter is examined… More >

Ibrahim Atawi¹, Sherif Zaid^1,2,3,*

Intelligent Automation & Soft Computing, Vol.31, No.1, pp. 449-469, 2022, DOI:10.32604/iasc.2022.019959

Abstract Transformerless inverters have become an important integration of the modern photovoltaic (PV) grid-tied systems. Unfortunately, it has a general safety problem regarding the earth leakage current that must be less than the recommended standards. Lately, the H7 transformerless inverter, which is a three-phase inverter with an additional switch on the DC side, is introduced to mitigate the earth leakage current. Different modulation techniques and controllers are proposed to optimize its performance. This paper proposed the application of model predictive control (MPC) to grid-connected H7 transformerless inverter supplied by the PV power system. In modeling the system, the grid inductance has… More >

Wei Zhang^1,2, Qihui Ling^1,2,*, Qiancheng Zhao^1,2, Hushu Wu³

Energy Engineering, Vol.118, No.5, pp. 1515-1535, 2021, DOI:10.32604/EE.2021.014162

Abstract The condition monitoring and fault diagnosis have been identified as the key to achieving higher availabilities of wind turbines. Numerous studies show that the open-circuit fault is a significant contributor to the failures of wind turbine converter. However, the multiple faults combinations and the influence of wind speed changes abruptly, grid voltage sags and noise interference have brought great challenges to fault diagnosis. Accordingly, concerning the open-circuit fault of converters in direct-driven PMSG wind turbine, a diagnostic method for multiple open-circuit faults is proposed in this paper, which is divided into two tasks: The first one is the fault detection… More >

Lei Zhang^*, Dejian Yang, Lei Ren, Yun Cheng, Qiufeng Yan, Yinlong Yuan

Energy Engineering, Vol.118, No.4, pp. 1155-1170, 2021, DOI:10.32604/EE.2021.014549

Abstract As a wide bandgap power electronics device, the SiC MOSFET has a lot of advantages over the traditional Si IGBT. Replacing the Si IGBT with the SiC MOSFET in the existing power electronics converter is an effective means to improve the performance and promote the upgrading of the traditional converter. Generally, in order to make full use of its advantages of the SiC MOSFET, the Si IGBT in the traditional power electronics circuit cannot be simply replaced by the SiC MOSFET, but the main circuit and the driver circuit need to be redesigned because the oscillation problem and the cross-talk… More >

Van-Truong Truong¹, Anand Nayyar^2,*, Showkat Ahmad Lone³

CMC-Computers, Materials & Continua, Vol.68, No.2, pp. 1615-1635, 2021, DOI:10.32604/cmc.2021.016922

Abstract Wireless sensor network (WSN) is considered as the fastest growing technology pattern in recent years because of its applicability in varied domains. Many sensor nodes with different sensing functionalities are deployed in the monitoring area to collect suitable data and transmit it to the gateway. Ensuring communications in heterogeneous WSNs, is a critical issue that needs to be studied. In this research paper, we study the system performance of a heterogeneous WSN using LoRa–Zigbee hybrid communication. Specifically, two Zigbee sensor clusters and two LoRa sensor clusters are used and combined with two Zigbee-to-LoRa converters to communicate in a network managed… More >

G. Indira Kishore¹, M. Premkumar^1,*, Ramesh Kumar Tripathi², Chandra Sekhar Nalamati²

Energy Engineering, Vol.118, No.2, pp. 199-209, 2021, DOI:10.32604/EE.2021.014079

Abstract Renewable energy with sources such as photovoltaic (PV) or fuel cells can be utilized for the generation of electrical power. But these sources generate fewer voltage values and therefore require high gain converters to match with DC bus voltage in microgrids. These high gain converters can be implemented with switched capacitors to meet the required DC bus voltage. Switched capacitors operate in a series and parallel combination during switching operation and produce high static gain, limits reverse voltage that appears across the components. A novel converter is proposed that satisfies all the features such as high voltage gain, only one… More >

Chi Zhang, Yong Shi^*, Xuwei Gui

Energy Engineering, Vol.118, No.2, pp. 341-361, 2021, DOI:10.32604/EE.2021.014229

Abstract To realize effective utilization of renewable energy sources, a novel polymorphic topology with hybrid control strategy based LLC resonant converter was analyzed and designed in this paper. By combining the merits of a full bridge LLC resonant converter, three-level half bridge LLC resonant converter, and variable frequency control mode, the converter realizes an intelligent estimation of input voltage by automatically changing its internal circuit topology. Under this control strategy, different input voltages determine different operation modes. This is achieved in full bridge LLC mode when the input voltage is low. If the input voltage rises to a certain level, it… More >