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Simulation and Experimental Analysis of an Impulse Voltage Generator
Carlos Favela,
Jesus Gonzalez,
Jose Hernandez-Avila,
Marco Arjona,
Concepcion Hernandez,
Esau Caro
Issue:
Volume 9, Issue 4, August 2021
Pages:
93-99
Received:
19 June 2021
Accepted:
28 June 2021
Published:
6 July 2021
Abstract: This paper presents the simulation and experimental analysis of an impulse voltage generator (IVG) used for atmospheric discharge voltage tests. The electrical equivalent circuit of the IVG was simulated using the electromagnetic transients program EMTP-VR. Besides the simulation of the generator operation, it was necessary to make a detailed revision of the IVG components and determine their working condition to carry the laboratory experiments. The lack of a high DC voltage source to feed the IVG led to developing a high-voltage dc supply. Although the IVG was designed and built in February 1982, this equipment was out of operation due to its DC power supply failure. Due to the interest in rehabilitating the equipment to perform high voltage experiments, and with the need to characterize insulation materials and electrical equipment subject to electrical stress, it was decided to put it back into operation. Capacitor tests were carried out for each IVG stage to determine if they fulfilled the electrical charging function. Other components were also repaired, such as damaged resistances and sphere gaps. The impulse generator was configured with a maximum of six stages which is half of the original design. Before doing an experiment with the IVG, a simulation analysis was made to study the IVG. The simulation results allow evaluating before the experimentation whether the impulse generator is working correctly; the model allows to analyze the charge and discharge of each capacitor and the electrical currents at each branch of the IVG equivalent circuit. Performance Simulation and experimental results are presented to demonstrate the IVG functionality. The IVG will be used for carrying out insulation tests made by power engineering graduate students.
Abstract: This paper presents the simulation and experimental analysis of an impulse voltage generator (IVG) used for atmospheric discharge voltage tests. The electrical equivalent circuit of the IVG was simulated using the electromagnetic transients program EMTP-VR. Besides the simulation of the generator operation, it was necessary to make a detailed revis...
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Cluster Head Selection and Routing Protocol for Wireless Sensor Networks (WSNs) Based on Software-Defined Network (SDN) Via Game of Theory
Seyed Salar Sefati,
Sara Ghiasi Tabrizi
Issue:
Volume 9, Issue 4, August 2021
Pages:
100-115
Received:
31 May 2021
Accepted:
6 July 2021
Published:
23 July 2021
Abstract: There is a way to prolong the life of sensor networks according to which a hierarchical routing algorithm is used intelligently, which employs all network elements in data transmission. Clustering the nodes is one of the best methods that can significantly increase the network life. Making a cluster, selecting a Cluster Head (CH) and data transmission in Wireless Sensor Network (WSN) are the issues that affect energy consumption. Software-Defined Networks (SDN) are a modern network architecture that distinguishes the network control panel from the data plate also this architecture cause the network utilizing is increased, and the operational cost is reduced. This method also causes creativity and perfection in the network area. Moreover, the possibility of implementing management protocols, including traffic management, which is an inevitable part of networks, can be implemented in SDN with a higher level of flexibility. In this paper, the CH has selected trough game theory, which sends data with the help of game theory rewards and calculating the geographical location of other nodes. Then, high-priority data is sent according to the proposed algorithm with the help of game theory. The simulation results in NS3 software show that the proposed method has obtained acceptable results compared with Artificial Bee Colony algorithm (ABC), Genetic Algorithm (GA), Cuckoo Search algorithm (CS), Firefly algorithm (FA) and Grey Wolf Optimization Algorithm (GWO).
Abstract: There is a way to prolong the life of sensor networks according to which a hierarchical routing algorithm is used intelligently, which employs all network elements in data transmission. Clustering the nodes is one of the best methods that can significantly increase the network life. Making a cluster, selecting a Cluster Head (CH) and data transmiss...
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Development the Measurement System of the Multi-Channel Frequency Standard Comparison
Zhang Yue,
Liu Yanqi,
Lin Tao,
Yuan Xiaodi,
Zhang Ammin,
Wang Yuzhuo
Issue:
Volume 9, Issue 4, August 2021
Pages:
116-122
Received:
14 July 2021
Accepted:
29 July 2021
Published:
4 August 2021
Abstract: This paper introduces a measurement system and method of high-speed sampling and full digital for the comparison of multi-channel frequency standard. The hardware of the system consists of 4 parts: A: Impedance matching module (After matching with the impedance of the acquisition circuit, the two input signals are transformed into suitable amplitude, and then transformed into digital signals by the high-speed acquisition circuit). B: High speed data acquisition module. C: Data real-time processing module. D: Calculation module for phase difference and frequency stability. The system not only can achieve real-time processing under the minimum computing resources, but also provide the upper computer with complete information and equivalent frequency data with small amount of data. Moreover, the fast and high-precision calculation of phase difference and frequency stability can be achieved by improving the calculation process. The software of the system meets the requirements for the technical specifications of national metrology. Compared with domestic and foreign frequency standard comparators, the interface of software is more friendly, the operation is more convenient, and it has a strong ability to analyze and process data. The test results show that the uncertainty of the system is better than 1.5 ×10-13 (sampling time is 1 second), which is consistent with Russian VCH-315 index.
Abstract: This paper introduces a measurement system and method of high-speed sampling and full digital for the comparison of multi-channel frequency standard. The hardware of the system consists of 4 parts: A: Impedance matching module (After matching with the impedance of the acquisition circuit, the two input signals are transformed into suitable amplitud...
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A Fast Switching Current Controlled DC/DC Converter for Automotive Applications
Osvaldo Gasparri,
Albino Pidutti,
Paolo Del Croce,
Andrea Baschirotto
Issue:
Volume 9, Issue 4, August 2021
Pages:
123-128
Received:
7 June 2021
Accepted:
23 July 2021
Published:
7 August 2021
Abstract: Automotive industry requires integrated circuits with both low cost, to maintain product competitiveness, and high efficiency, moving towards solutions as green as possible. Each electronic device within the car needs for a regulator to provide a steady supply to ensure correct and safe operation. Among all regulator, DC/DC Converters are the most valid solution to achieve a high efficiency-price ratio. The DC/DC Converter needs for a control loop to monitor the load operation. The basic control loop topologies are well known in the state-of-the-art. The paper presents a DC/DC Buck Converter for automotive applications designed in low cost technology with an upgraded version of the Peak Current Mode Control which uses a constant off-time. For chip area reduction, an n-channel power-DMOS is chosen as power transistor. The design of each block composing the circuit is presented. To guarantee DC-DC Buck converters high-efficiency and low cost (in terms of external components) increasing switching frequency is mandatory. A 1.5 MHz switching frequency has been chosen to reduce external components size. The device is optimized by design to be able to achieve 94.4% efficiency using a 3V 3A load. The post-layout simulations of the system are shown, confirming the expected circuit behavior also including the presence of wiring parasites. A PCB is also designed to test the packaged die to ultimately demonstrate the chip’s robustness and suitability in a real automotive application.
Abstract: Automotive industry requires integrated circuits with both low cost, to maintain product competitiveness, and high efficiency, moving towards solutions as green as possible. Each electronic device within the car needs for a regulator to provide a steady supply to ensure correct and safe operation. Among all regulator, DC/DC Converters are the most ...
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On Some Properties of the Quasi-Moment-Method Pathloss Model Calibration
Ayorinde Ayotunde,
Adelabu Michael,
Muhammed Hisham,
Okewole Francis,
Mowete Ike
Issue:
Volume 9, Issue 4, August 2021
Pages:
129-146
Received:
15 July 2021
Accepted:
2 August 2021
Published:
7 August 2021
Abstract: Certain properties of the recently introduced Quasi-Moment-Method (QMM) for the calibration of basic radiowave propagation pathloss models are systematically examined in this paper. Using measurement data concerning three different routes located in a smart campus environment and made available in the open literature, the paper, in particular, investigates the effects of size of pathloss measurement data on the outcomes of the QMM calibration of nine basic pathloss models: namely, COST 231-urban and sub-urban cities models, ECC33-large and medium sized cities models, and the Egli, Ericsson, Hata, Lee, and SUI-‘Terrain A’ models. Computational results reveal that for the data sizes considered, and in the cases of the basic COST 231 and Hata models, which share identical correction factors for receiver antenna height, the ‘model calibration matrix’ becomes ill-conditioned for one choice of basis functions. The corresponding calibrated models, however, still predict pathloss with accuracy typical of the QMM. For example, Root Mean Square Error (RMSE) outcomes of predictions due to the calibration of these models, emerged as approximately the same for these three models; with values of 6.03 dB (Route A), 7.96 dB (Route B), and 6.19 dB (Route C). The results also show that when model calibration utilizes measurement data for distances further away from the transmitters (by ignoring measurement data for radial distances less than 100m away from the transmitters) significant improvements in RMSE metrics were recorded. The paper, in terms of the eigenvalues of the model calibration matrices, further examined the responses of these models to calibration with large-sized measurement data, to find that the model calibration matrices remained characterized, in each case, by a distinctly dominant eigenvalue. An important conclusion arising from the results of the investigations is that whereas the QMM model calibration process may lead, in some cases, and when large-sized measurement data is involved, to ‘badly-scaled’ model calibration matrices, the calibrated models still record very good assessment metrics. Computational results also reveal that with large-sized data sets, QMM models yield pathloss predictions with excellent (close to 0 dB) mean prediction errors.
Abstract: Certain properties of the recently introduced Quasi-Moment-Method (QMM) for the calibration of basic radiowave propagation pathloss models are systematically examined in this paper. Using measurement data concerning three different routes located in a smart campus environment and made available in the open literature, the paper, in particular, inve...
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