Next Issue
Previous Issue

Table of Contents

Electronics, Volume 8, Issue 2 (February 2019)

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
Cover Story (view full-size image) In the past decade, an indisputable consolidation of unmanned aerial vehicles (UAVs) has been [...] Read more.
View options order results:
result details:
Displaying articles 1-140
Export citation of selected articles as:
Open AccessArticle
Development of a Low-Cost Fault Detector for Photovoltaic Module Array
Electronics 2019, 8(2), 255; https://doi.org/10.3390/electronics8020255
Received: 19 January 2019 / Revised: 12 February 2019 / Accepted: 18 February 2019 / Published: 25 February 2019
Viewed by 633 | PDF Full-text (5530 KB) | HTML Full-text | XML Full-text
Abstract
This study proposes a binary search-based fault detection system for photovoltaic (PV) modules to ameliorate the deficiencies in the existing fault detectors for PV module arrays. The proposed system applies a single-chip microcontroller to execute the binary search algorithm. Moreover, to overcome multi-node [...] Read more.
This study proposes a binary search-based fault detection system for photovoltaic (PV) modules to ameliorate the deficiencies in the existing fault detectors for PV module arrays. The proposed system applies a single-chip microcontroller to execute the binary search algorithm. Moreover, to overcome multi-node voltage detection and reduce the number of integrated circuit components, an analog switch is used to perform detection channel switching; the detection results are displayed on a software platform developed using Visual C#. The proposed system does not require learning to execute the fault diagnosis of PV module arrays and has advantages including high accuracy and low construction costs. Finally, to verify the feasibility of the proposed system, this study simulated the abnormal situations of actual modules and applied the binary search algorithm for maximum power point tracking to detect malfunctions of the PV module arrays. Full article
Figures

Figure 1

Open AccessArticle
Analyzing Electrical Performance and Thermal Coupling of Supercapacitor Assembled Using Phosphorus-Doped Porous Carbon/Graphene Composite
Electronics 2019, 8(2), 254; https://doi.org/10.3390/electronics8020254
Received: 11 February 2019 / Accepted: 21 February 2019 / Published: 25 February 2019
Viewed by 570 | PDF Full-text (5433 KB) | HTML Full-text | XML Full-text
Abstract
A novel phosphorus-doped porous carbon/graphene composite was adopted as electrode material of super-capacitor, which showed excellent electrochemical performance compared with carbon material without phosphorus heteroatom by means of cyclic voltammetry, the charge/discharge property, impedance characteristics, cycle life, and stability. The P-enriched carbons sample [...] Read more.
A novel phosphorus-doped porous carbon/graphene composite was adopted as electrode material of super-capacitor, which showed excellent electrochemical performance compared with carbon material without phosphorus heteroatom by means of cyclic voltammetry, the charge/discharge property, impedance characteristics, cycle life, and stability. The P-enriched carbons sample offered an outstanding capacitive behavior, which had specific capacitance 277 F/g and was able to withstand at a wide voltage window of 1.6 V with 90.8% performance retention after 10,000 cycles at a current density of 10 Ag−1, providing a higher energy density 26.42 Wh/kg. In addition, because the thermal effect in charge and discharge process can make the supercapacitor temperature rise rapidly in a short time and affect the electrical performance, temperature characteristic is one of the important characteristics to be considered in practical application. In this paper, a two-dimensional thermal model for commonly used coiling supercapacitor with p-doped porous carbon/graphene composite as electrode material was established, and the temperature distribution of supercapacitor and the variation of internal temperature under different conditions were analyzed by finite element method. The results show that the maximum temperature appears near the center, and the maximum temperature is related to the applied current and the number of cycles. With the increase of the current, the maximum internal temperature is increased sharply, and it is kept constant after the number of cycles reaches a certain value. Cooling measures should be taken when the maximum temperature exceeds the allowable temperature range. Full article
(This article belongs to the Special Issue Innovative Technologies in Green Power Systems)
Figures

Figure 1

Open AccessArticle
A 5GS/s 8-bit ADC with Self-Calibration in 0.18 μm SiGe BiCMOS Technology
Electronics 2019, 8(2), 253; https://doi.org/10.3390/electronics8020253
Received: 4 January 2019 / Revised: 18 February 2019 / Accepted: 20 February 2019 / Published: 25 February 2019
Viewed by 700 | PDF Full-text (4400 KB) | HTML Full-text | XML Full-text
Abstract
A 5 GS/s 8-bit analog-to-digital converter (ADC) implemented in 0.18 μm SiGe BiCMOS technology has been demonstrated. The proposed ADC is based on two-channel time-interleaved architecture, and each sub-ADC employs a two-stage cascaded folding and interpolating topology of radix-4. An open loop track-and-hold [...] Read more.
A 5 GS/s 8-bit analog-to-digital converter (ADC) implemented in 0.18 μm SiGe BiCMOS technology has been demonstrated. The proposed ADC is based on two-channel time-interleaved architecture, and each sub-ADC employs a two-stage cascaded folding and interpolating topology of radix-4. An open loop track-and-hold amplifier with enhanced linearity is designed to meet the dynamic performance requirement. The on-chip self-calibration technique is introduced to compensate the interleaving mismatches between two sub-ADCs. Measurement results show that the spurious free dynamic range (SFDR) stays above 44.8 dB with a peak of 53.52 dB, and the effective number of bits (ENOB) is greater than 5.8 bit with a maximum of 6.97 bit up to 2.5 GS/s. The ADC exhibits a differential nonlinearity (DNL) of -0.31/+0.23 LSB (least significant bit) and an integral nonlinearity (INL) of -0.68/+0.68 LSB, respectively. The chip occupies an area of 3.9 × 3.6 mm2, consumes a total power of 2.8 W, and achieves a figure of merit (FoM) of 10 pJ/conversion step. Full article
(This article belongs to the Section Microelectronics and Optoelectronics)
Figures

Figure 1

Open AccessArticle
City Marathon Active Timing System Using Bluetooth Low Energy Technology
Electronics 2019, 8(2), 252; https://doi.org/10.3390/electronics8020252
Received: 9 November 2018 / Revised: 29 January 2019 / Accepted: 1 February 2019 / Published: 22 February 2019
Viewed by 698 | PDF Full-text (10149 KB) | HTML Full-text | XML Full-text
Abstract
This study proposes and implements city marathon timing technology using Bluetooth Low-Energy (BLE) communication technology. This study also performs a prevalidation of the athletes’ physiological sensory data that is sent out by the same timing system—the BLE active communication technology. In order to [...] Read more.
This study proposes and implements city marathon timing technology using Bluetooth Low-Energy (BLE) communication technology. This study also performs a prevalidation of the athletes’ physiological sensory data that is sent out by the same timing system—the BLE active communication technology. In order to verify the timing and positioning technology, 621 K records of static measurement of the Received Signal Strength Indicator (RSSI) were first collected. The trend of the RSSI between the location and the BLE Receiver when the runners carried a BLE Tag was analyzed. Then, the difference between the runners’ passing timestamp and the runners’ actual passing time when the runners carried a BLE Tag and ran past the BLE Receivers was dynamically recorded and analyzed. Additionally, the timing sensing rate when multiple runners ran past the BLE Receivers was verified. In order to confirm the accuracy of the time synchronization in the remote timing device, the timing error, synced by the Network Time Protocol (NTP), was analyzed. A global positioning system (GPS) signal was used to enhance the time synchronization’s accuracy. Additionally, the timing devices were separated by 15 km, and it was verified that they remained within the timing error range of 1 ms. The BLE communication technology has at least one more battery requirement than traditional passive radio frequency identification (RFID) timing devices. Therefore, the experiment also verified that the BLE Tag of this system can continue to operate for at least 48 h under normal conditions. Based on the above experimental results, it is estimated that the system can provide a timing error of under ±156 ms for each athlete. The system can also meet the scale of the biggest international city marathon event. Full article
(This article belongs to the Special Issue RFID, WPT and Energy Harvesting)
Figures

Figure 1

Open AccessArticle
An Inner- and Outer-Fed Dual-Arm Archimedean Spiral Antenna for Generating Multiple Orbital Angular Momentum Modes
Electronics 2019, 8(2), 251; https://doi.org/10.3390/electronics8020251
Received: 12 January 2019 / Revised: 1 February 2019 / Accepted: 6 February 2019 / Published: 22 February 2019
Cited by 1 | Viewed by 642 | PDF Full-text (8183 KB) | HTML Full-text | XML Full-text
Abstract
Orbital angular momentum (OAM) beams have attracted great attention owing to their excellent performances in imaging and communication. In this paper, a dual-arm Archimedean spiral antenna (DASA) is proposed to generate multiple OAM states with positive and negative values by feeding at the [...] Read more.
Orbital angular momentum (OAM) beams have attracted great attention owing to their excellent performances in imaging and communication. In this paper, a dual-arm Archimedean spiral antenna (DASA) is proposed to generate multiple OAM states with positive and negative values by feeding at the inner and outer ends, respectively. The topological charge of radiated vortex waves is reconfigurable by tuning the operating frequency. Dual-mode OAM states are generated at different working frequencies (l = ±1 at 3 GHz, l = ±2 at 4 GHz, and l = ±3 at 4.8 GHz). Both the simulation and measurement results demonstrate that OAM beams can be generated effectively by the DASA. In addition, a conical cavity is used to increase the gain of the proposed DASA for more than 5 dBi in comparison to the traditional cylindrical cavity. Furthermore, the qualities of the generated OAM modes by the proposed DASA have been evaluated at different operating frequencies of 3 GHz, 4 GHz, and 4.8 GHz, respectively. The OAM modes purities of l = −1, −2, −3, 1, 2, and 3 are predominate with the proportion of about 81%, 70%, 74%, 78%, 77%, and 75%, respectively. Our results demonstrate that the proposed DASA has great potentials in OAM multiplexing communication systems. Full article
(This article belongs to the Section Microwave and Wireless Communications)
Figures

Figure 1

Open AccessArticle
Efficient Neural Network Implementations on Parallel Embedded Platforms Applied to Real-Time Torque-Vectoring Optimization Using Predictions for Multi-Motor Electric Vehicles
Electronics 2019, 8(2), 250; https://doi.org/10.3390/electronics8020250
Received: 31 December 2018 / Revised: 5 February 2019 / Accepted: 13 February 2019 / Published: 22 February 2019
Cited by 1 | Viewed by 799 | PDF Full-text (3831 KB) | HTML Full-text | XML Full-text
Abstract
The combination of machine learning and heterogeneous embedded platforms enables new potential for developing sophisticated control concepts which are applicable to the field of vehicle dynamics and ADAS. This interdisciplinary work provides enabler solutions -ultimately implementing fast predictions using neural networks (NNs) on [...] Read more.
The combination of machine learning and heterogeneous embedded platforms enables new potential for developing sophisticated control concepts which are applicable to the field of vehicle dynamics and ADAS. This interdisciplinary work provides enabler solutions -ultimately implementing fast predictions using neural networks (NNs) on field programmable gate arrays (FPGAs) and graphical processing units (GPUs)- while applying them to a challenging application: Torque Vectoring on a multi-electric-motor vehicle for enhanced vehicle dynamics. The foundation motivating this work is provided by discussing multiple domains of the technological context as well as the constraints related to the automotive field, which contrast with the attractiveness of exploiting the capabilities of new embedded platforms to apply advanced control algorithms for complex control problems. In this particular case we target enhanced vehicle dynamics on a multi-motor electric vehicle benefiting from the greater degrees of freedom and controllability offered by such powertrains. Considering the constraints of the application and the implications of the selected multivariable optimization challenge, we propose a NN to provide batch predictions for real-time optimization. This leads to the major contribution of this work: efficient NN implementations on two intrinsically parallel embedded platforms, a GPU and a FPGA, following an analysis of theoretical and practical implications of their different operating paradigms, in order to efficiently harness their computing potential while gaining insight into their peculiarities. The achieved results exceed the expectations and additionally provide a representative illustration of the strengths and weaknesses of each kind of platform. Consequently, having shown the applicability of the proposed solutions, this work contributes valuable enablers also for further developments following similar fundamental principles. Full article
Figures

Graphical abstract

Open AccessFeature PaperReview
Perylene-Diimide Molecules with Cyano Functionalization for Electron-Transporting Transistors
Electronics 2019, 8(2), 249; https://doi.org/10.3390/electronics8020249
Received: 30 January 2019 / Revised: 14 February 2019 / Accepted: 18 February 2019 / Published: 22 February 2019
Viewed by 756 | PDF Full-text (8871 KB) | HTML Full-text | XML Full-text
Abstract
Core-cyanated perylene diimide (PDI_CY) derivatives are molecular compounds exhibiting an uncommon combination of appealing properties, including remarkable oxidative stability, high electron affinities, and excellent self-assembling properties. Such features made these compounds the subject of study for several research groups aimed at developing electron-transporting [...] Read more.
Core-cyanated perylene diimide (PDI_CY) derivatives are molecular compounds exhibiting an uncommon combination of appealing properties, including remarkable oxidative stability, high electron affinities, and excellent self-assembling properties. Such features made these compounds the subject of study for several research groups aimed at developing electron-transporting (n-type) devices with superior charge transport performances. After about fifteen years since the first report, field-effect transistors based on PDI_CY thin films are still intensely investigated by the scientific community for the attainment of n-type devices that are able to balance the performances of the best p-type ones. In this review, we summarize the main results achieved by our group in the fabrication and characterization of transistors based on PDI8-CN2 and PDIF-CN2 molecules, undoubtedly the most renowned compounds of the PDI_CY family. Our attention was mainly focused on the electrical properties, both at the micro and nanoscale, of PDI8-CN2 and PDIF-CN2 films deposited using different evaporation techniques. Specific topics, such as the contact resistance phenomenon, the bias stress effect, and the operation in liquid environment, have been also analyzed. Full article
(This article belongs to the Special Issue Organic Semiconductors and Their Electronic Application)
Figures

Figure 1

Open AccessArticle
Cyber-Physical System Framework for Measurement and Analysis of Physical Activities
Electronics 2019, 8(2), 248; https://doi.org/10.3390/electronics8020248
Received: 17 January 2019 / Revised: 16 February 2019 / Accepted: 20 February 2019 / Published: 22 February 2019
Viewed by 786 | PDF Full-text (3003 KB) | HTML Full-text | XML Full-text
Abstract
Several recent studies in Cyber-Physical Systems (CPS) focus on monitoring human movement and capturing data for further processing and analysis. However, there is a lack of studies that address the configurability and modularity of these systems, which is important for designing customized systems [...] Read more.
Several recent studies in Cyber-Physical Systems (CPS) focus on monitoring human movement and capturing data for further processing and analysis. However, there is a lack of studies that address the configurability and modularity of these systems, which is important for designing customized systems with customized devices. We propose a solution to solve this through a modular framework that automatically recognizes and configures new devices and provides real-time data wirelessly. The proposed framework creates a Digital Twin of the physical device and mirrors its attributes and sensory information into the cyber world so they can be used in real-time and post-routine analysis. As a proof of concept, a configurable CPS model for physical activities monitoring is designed and implemented. The designed gait monitoring and analysis system delivers spatiotemporal data from multiple multi-sensory devices to a central data handling and backup cloud server over conventional IEEE802.11 Wi-Fi. An experiment involving a young athlete examined whether or not the CPS components would recognize each other over foreign networks and communicate accurate information. Full article
(This article belongs to the Special Issue Cyber-Physical Systems)
Figures

Graphical abstract

Open AccessArticle
A Novel Three-Switch Z-Source SEPIC Inverter
Electronics 2019, 8(2), 247; https://doi.org/10.3390/electronics8020247
Received: 14 January 2019 / Revised: 19 February 2019 / Accepted: 19 February 2019 / Published: 21 February 2019
Cited by 1 | Viewed by 651 | PDF Full-text (3726 KB) | HTML Full-text | XML Full-text
Abstract
In this paper, a novel single-phase transformerless Z-source inverter (ZSI) derived from the basic SEPIC topology, which is named SEPIC-based ZSI, is proposed. The negative end of the input DC voltage of this topology is directly connected to the load and grounded, which [...] Read more.
In this paper, a novel single-phase transformerless Z-source inverter (ZSI) derived from the basic SEPIC topology, which is named SEPIC-based ZSI, is proposed. The negative end of the input DC voltage of this topology is directly connected to the load and grounded, which can completely eliminate leakage current. Furthermore, this topology has some attractive characteristics such as buck–boost capability, impressive voltage gain, linear voltage gain is realized by a simple control method, and so on. The theoretical design and simulation results are demonstrated by corresponding experiments carried out on a 500 W laboratory prototype controlled by using a DSP TMS320F28335 controller combined with a FPGA SPARTAN-6. Full article
(This article belongs to the Special Issue Power Converters in Power Electronics)
Figures

Figure 1

Open AccessArticle
An Improved Algorithm for Extracting Subtle Features of Radiation Source Individual Signals
Electronics 2019, 8(2), 246; https://doi.org/10.3390/electronics8020246
Received: 29 January 2019 / Revised: 16 February 2019 / Accepted: 18 February 2019 / Published: 21 February 2019
Cited by 1 | Viewed by 601 | PDF Full-text (1877 KB) | HTML Full-text | XML Full-text
Abstract
With the rapid development of communication and information technology, it is difficult for traditional signal detection and recognition methods to accurately acquire and identify the intelligence under complex environments. In order to solve this problem, this paper proposes a subtle feature extraction and [...] Read more.
With the rapid development of communication and information technology, it is difficult for traditional signal detection and recognition methods to accurately acquire and identify the intelligence under complex environments. In order to solve this problem, this paper proposes a subtle feature extraction and recognition algorithm for radiation source individual signals based on multidimensional hybrid features. Firstly, Hilbert transform was performed on the radiation source signals from 10 identical radio devices, and the subtle features of different radiation sources’ signals were extracted. Then, traditional principal component analysis (PCA) algorithm was used to extract and reduce the principal components of the extracted feature data sets. Aiming at the insufficiency of traditional PCA algorithm, an improved principal component analysis algorithm was proposed. At last, a gray relation algorithm was used to classify and identify the radiation source individual signals, and the recognition rate was calculated. Experimental results show that Hilbert transform combined with the improved PCA algorithm can achieve a recognition rate of 99.67% for the "fingerprint" features of radiation source individual signals under the signal-to-noise ratio (SNR) of 20 dB. Compared with the traditional algorithms, the recognition rate increased by 5.67%. Therefore, it provides a powerful theoretical basis for extracting subtle features of radiation source devices under complex electromagnetic environments. Full article
(This article belongs to the Section Microwave and Wireless Communications)
Figures

Figure 1

Open AccessArticle
Sufficient Condition-Based Stability Analysis of a Power Converter Applied Switching Transient Waveform Modification Using Kharitonov’s Theorem
Electronics 2019, 8(2), 245; https://doi.org/10.3390/electronics8020245
Received: 31 December 2018 / Revised: 15 February 2019 / Accepted: 19 February 2019 / Published: 21 February 2019
Viewed by 563 | PDF Full-text (1503 KB) | HTML Full-text | XML Full-text
Abstract
The rapid switching action of power metal-oxide-semiconductor field-effect transistor (MOSFET) causes high-level electromagnetic interference (EMI) in power converters. The switching transient waveform modification method realized by closed-loop gate drive has been recognized as an effective high-frequency EMI reduction approach. However, feedback control of [...] Read more.
The rapid switching action of power metal-oxide-semiconductor field-effect transistor (MOSFET) causes high-level electromagnetic interference (EMI) in power converters. The switching transient waveform modification method realized by closed-loop gate drive has been recognized as an effective high-frequency EMI reduction approach. However, feedback control of power MOSFET in the saturation region would introduce stability problems. This paper presents a sufficient condition-based stability analysis of all the operating points during turn-off using Kharitonov’s theorem. Firstly, a small-signal MOSFET model during turn-off was used to derive the closed-loop system transfer function. The nonlinear capacitances and the rest constant parameters of the small-signal model were determined based on the device characteristics and the expected outcome of the drain-source voltage. Then we split the turn-off switching transient into several subintervals, during which the system characteristic equation became an interval polynomial due to the nonlinear capacitances. Finally, Kharitonov’s theorem was applied in each subinterval to evaluate the stability, thereby achieving the overall system stability analysis during turn-off. Experiments were conducted to investigate the system’s stability and the results confirmed the validity of the proposed analysis. This work presents an implementable design guideline for the applied switching transient waveform modification of power converters via closed-loop gate drive. Full article
(This article belongs to the Special Issue Advanced Power Conversion Technologies)
Figures

Figure 1

Open AccessArticle
A Design Rule to Reduce the Human Body Effect on Wearable PIFA Antennas
Electronics 2019, 8(2), 244; https://doi.org/10.3390/electronics8020244
Received: 30 January 2019 / Revised: 12 February 2019 / Accepted: 14 February 2019 / Published: 21 February 2019
Cited by 2 | Viewed by 696 | PDF Full-text (10084 KB) | HTML Full-text | XML Full-text | Correction
Abstract
The robustness of wearable Ultra-High Frequency (UHF)-band planar inverted-F Antennas (PIFAs) with respect to coupling with the human body is an extremely difficult challenge for the designer. In this work a design strategy is presented to help the designer to adequately shape and [...] Read more.
The robustness of wearable Ultra-High Frequency (UHF)-band planar inverted-F Antennas (PIFAs) with respect to coupling with the human body is an extremely difficult challenge for the designer. In this work a design strategy is presented to help the designer to adequately shape and extend the antenna ground plane, which has been derived by accurately analyzing the distribution of the electric and magnetic energy densities of the antenna in a region around the antenna borders. The optimal extension of the ground plane will be discussed for three different grounded antennas, both in terms of free space wavelength, and in terms of electric energy density magnitude. Following these rules, the antenna robustness with respect to the coupling with the human body can be significantly improved, but with a minimal impact on the antenna size. The antenna robustness has been successfully tested considering several models for the human phantom in the simulation environment. The numerical simulations, performed using Computer Simulation Technology (CST) Microwave Studio, have been confirmed by experimental data measured for one of the analyzed grounded antenna configurations. Full article
(This article belongs to the Special Issue Intelligent Antennas)
Figures

Figure 1

Open AccessArticle
LAP-SLAM: A Line-Assisted Point-Based Monocular VSLAM
Electronics 2019, 8(2), 243; https://doi.org/10.3390/electronics8020243
Received: 12 February 2019 / Revised: 15 February 2019 / Accepted: 17 February 2019 / Published: 20 February 2019
Viewed by 728 | PDF Full-text (3541 KB) | HTML Full-text | XML Full-text
Abstract
While the performance of the state-of-the-art point-based VSLAM (vision simultaneous localization and mapping) systems in well textured sequences is impressive, their performance in poorly textured situations is not satisfactory enough. A sensible alternative or addition is to consider lines. In this paper, we [...] Read more.
While the performance of the state-of-the-art point-based VSLAM (vision simultaneous localization and mapping) systems in well textured sequences is impressive, their performance in poorly textured situations is not satisfactory enough. A sensible alternative or addition is to consider lines. In this paper, we propose a novel line-assisted point-based VSLAM algorithm (LAP-SLAM). Our algorithm uses lines without descriptor matching, and the lines are used to assist the computation conducted by points. To the best of our knowledge, this paper proposes a new way to include line information in VSLAM. The basic idea is to use the collinear relationship of points to optimize the current point-based VSLAM algorithm. In LAP-SLAM, we propose a practical algorithm to match lines and compute the collinear relationship of points, a line-assisted bundle adjustment approach and a modified perspective-n-point (PnP) approach. We built our system based on the architecture and pipeline of ORB-SLAM. We evaluate the proposed method on a diverse range of indoor sequences in the TUM dataset and compare with point-based and point-line-based methods. The results show that the accuracy of our algorithm is close to point-line-based VSLAM systems with a much faster speed. Full article
(This article belongs to the Section Computer Science & Engineering)
Figures

Figure 1

Open AccessArticle
A Pseudo-Dynamic Delay Calculation Using Optimal Zone Segmentation for Ultra-Compact Ultrasound Imaging Systems
Electronics 2019, 8(2), 242; https://doi.org/10.3390/electronics8020242
Received: 12 January 2019 / Revised: 12 February 2019 / Accepted: 19 February 2019 / Published: 20 February 2019
Viewed by 577 | PDF Full-text (1729 KB) | HTML Full-text | XML Full-text
Abstract
The implementation of dynamic delay calculations (DDCs) is challenging for ultra-compact ultrasound imaging due to the enormous computation and power consumption requirements. Here, we present an efficient pseudo-DDC method based on optimal zone segmentation (PDC-Optimal), which significantly decreases these requirements relative to an [...] Read more.
The implementation of dynamic delay calculations (DDCs) is challenging for ultra-compact ultrasound imaging due to the enormous computation and power consumption requirements. Here, we present an efficient pseudo-DDC method based on optimal zone segmentation (PDC-Optimal), which significantly decreases these requirements relative to an unconstrained DDC method: reductions in flip-flops of 84.35% and in look-up tables of 94.19%, respectively. The reductions lead to an up to 94.53% lower dynamic power consumption and provide image quality comparable to the unconstrained DDC method. The proposed PDC-Optimal method also provides adaptive flexibility between beamforming accuracy and battery life using the delay error allowance, a user-definable parameter. A conventional pseudo-DDC method using uniform zone segmentation (PDC-Conv) presented substantial image degradation in the near imaging field when the same number of zone segments was used. Therefore, the PDC-Optimal method provides an efficient yet flexible DDC solution to improve the experiences for ultra-compact ultrasound imaging system users. Full article
(This article belongs to the Section Circuit and Signal Processing)
Figures

Figure 1

Open AccessArticle
Gallium Nitride Normally-Off Vertical Field-Effect Transistor Featuring an Additional Back Current Blocking Layer Structure
Electronics 2019, 8(2), 241; https://doi.org/10.3390/electronics8020241
Received: 31 December 2018 / Revised: 12 February 2019 / Accepted: 18 February 2019 / Published: 20 February 2019
Cited by 1 | Viewed by 742 | PDF Full-text (3852 KB) | HTML Full-text | XML Full-text
Abstract
A gallium nitride (GaN) semiconductor vertical field-effect transistor (VFET) has several attractive advantages such as high power density capability and small device size. Currently, some of the main issues hindering its development include the realization of normally off operation and the improvement of [...] Read more.
A gallium nitride (GaN) semiconductor vertical field-effect transistor (VFET) has several attractive advantages such as high power density capability and small device size. Currently, some of the main issues hindering its development include the realization of normally off operation and the improvement of high breakdown voltage (BV) characteristics. In this work, a trenched-gate scheme is employed to realize the normally off VFET. Meanwhile, an additional back current blocking layer (BCBL) is proposed and inserted into the GaN normally off VFET to improve the device performance. The electrical characteristics of the proposed device (called BCBL-VFET) are investigated systematically and the structural parameters are optimized through theoretical calculations and TCAD simulations. We demonstrate that the BCBL-VFET exhibits a normally off operation with a large positive threshold voltage of 3.5 V and an obviously increased BV of 1800 V owing to the uniform electric field distribution achieved around the gate region. However, the device only shows a small degradation of on-resistance (RON). The proposed scheme provides a useful reference for engineers in device fabrication work and will be promising for the applications of power electronics. Full article
Figures

Figure 1

Open AccessArticle
A Countermeasure against DPA on SIMON with an Area-Efficient Structure
Electronics 2019, 8(2), 240; https://doi.org/10.3390/electronics8020240
Received: 8 January 2019 / Revised: 14 February 2019 / Accepted: 19 February 2019 / Published: 20 February 2019
Viewed by 588 | PDF Full-text (8784 KB) | HTML Full-text | XML Full-text
Abstract
Differential power analysis (DPA) is an effective side channel attack method, which poses a critical threat to cryptographic algorithms, especially lightweight ciphers such as SIMON. In this paper, we propose an area-efficient countermeasure against DPA on SIMON based on the power randomization. Firstly, [...] Read more.
Differential power analysis (DPA) is an effective side channel attack method, which poses a critical threat to cryptographic algorithms, especially lightweight ciphers such as SIMON. In this paper, we propose an area-efficient countermeasure against DPA on SIMON based on the power randomization. Firstly, we review and analyze the architecture of SIMON algorithm. Secondly, we prove the threat of DPA attack to SIMON by launching actual DPA attack on SIMON 32/64 circuit. Thirdly, a low-cost power randomization scheme is proposed by combining fault injection with double rate technology, and the corresponding circuit design is implemented. To the best of our knowledge, this is the first scheme that applies the combination of fault injection and double rate technology to the DPA-resistance. Finally, the t-test is used to evaluate the security mechanism of the proposed designs with leakage quantification. Our experimental results show that the proposed design implements DPA-resistance of SIMON algorithm at certain overhead the cost of 47.7% LUTs utilization and 39.6% registers consumption. As compared to threshold implementation and bool mask, the proposed scheme has greater advantages in resource consumption. Full article
(This article belongs to the Special Issue Signal Processing and Analysis of Electrical Circuit)
Figures

Figure 1

Open AccessArticle
Two-Dimensional Imaging of Permittivity Distribution by an Activated Meta-Structure with a Functional Scanning Defect
Electronics 2019, 8(2), 239; https://doi.org/10.3390/electronics8020239
Received: 31 January 2019 / Revised: 14 February 2019 / Accepted: 18 February 2019 / Published: 20 February 2019
Cited by 1 | Viewed by 693 | PDF Full-text (6777 KB) | HTML Full-text | XML Full-text
Abstract
A novel 2D imaging method for permittivity imaging using a meta-structure with a functional scanning defect is proposed, working in the millimeter wave-range. The meta-structure we used here is composed of a perforated metal plate with subwavelength-holes and a needle-like conductor that can [...] Read more.
A novel 2D imaging method for permittivity imaging using a meta-structure with a functional scanning defect is proposed, working in the millimeter wave-range. The meta-structure we used here is composed of a perforated metal plate with subwavelength-holes and a needle-like conductor that can scan two-dimensionally just beneath the plate. The metal plate, which is referred to as a metal hole array (MHA) in this study, is known as a structure supporting propagation of spoof surface plasmon polaritons (SSPPs). High-frequency waves with frequencies higher than microwaves, including SSPPs, have the potential to detect signals from inner parts embedded beneath solid surfaces such as living cells or organs under the skin, without physical invasion, because of the larger skin depth penetration of millimeter wave-bands than optical wave-bands. Focused on activated SSPPs, the localized distortion of SSPP modes on an MHA is used in the proposed method to scan the electromagnetic properties of the MHA with a needle-like conductor (conductive probe), which is a kind of active defect-initiator. To show the validity of the proposed method, electromagnetic analyses of the localized distortions of wave fields were performed, and one- and two-dimensional imaging experiments were conducted with the aim of detecting both conductive and dielectric samples. The analytical results confirmed the localized distortion of the electric field distribution of SSPP modes and also indicated that the proposed method has scanning ability. In experimental studies, the detection of conductive and dielectric samples was successful, where the detected dielectrics contained pseudo-biological materials, with an accuracy on the order of millimeters. Finally, a biomedical diagnosis in the case of a rat lung is demonstrated by using the experimental system. These results indicate that the proposed method may be usable for non-invasive and low-risk biomedical diagnosis. Full article
(This article belongs to the Special Issue Engineering Metamaterials)
Figures

Figure 1

Open AccessFeature PaperArticle
Electron Affinity and Bandgap Optimization of Zinc Oxide for Improved Performance of ZnO/Si Heterojunction Solar Cell Using PC1D Simulations
Electronics 2019, 8(2), 238; https://doi.org/10.3390/electronics8020238
Received: 26 December 2018 / Revised: 4 February 2019 / Accepted: 14 February 2019 / Published: 20 February 2019
Cited by 3 | Viewed by 779 | PDF Full-text (1652 KB) | HTML Full-text | XML Full-text
Abstract
For further uptake in the solar cell industry, n-ZnO/p-Si single heterojunction solar cell has attracted much attention of the research community in recent years. This paper reports the influence of bandgap and/or electron affinity tuning of zinc oxide on the performance of n-ZnO/p-Si [...] Read more.
For further uptake in the solar cell industry, n-ZnO/p-Si single heterojunction solar cell has attracted much attention of the research community in recent years. This paper reports the influence of bandgap and/or electron affinity tuning of zinc oxide on the performance of n-ZnO/p-Si single heterojunction photovoltaic cell using PC1D simulations. The simulation results reveal that the open circuit voltage and fill factor can be improved significantly by optimizing valence-band and conduction-band off-sets by engineering the bandgap and electron affinity of zinc oxide. An overall conversion efficiency of more than 20.3% can be achieved without additional cost or any change in device structure. It has been found that the improvement in efficiency is mainly due to reduction in conduction band offset that has a significant influence on minority carrier current. Full article
Figures

Graphical abstract

Open AccessArticle
Data-Driven Control Techniques for Renewable Energy Conversion Systems: Wind Turbine and Hydroelectric Plants
Electronics 2019, 8(2), 237; https://doi.org/10.3390/electronics8020237
Received: 23 January 2019 / Revised: 12 February 2019 / Accepted: 18 February 2019 / Published: 20 February 2019
Viewed by 663 | PDF Full-text (528 KB) | HTML Full-text | XML Full-text
Abstract
The interest in the use of renewable energy resources is increasing, especially towards wind and hydro powers, which should be efficiently converted into electric energy via suitable technology tools. To this end, data-driven control techniques represent viable strategies that can be employed for [...] Read more.
The interest in the use of renewable energy resources is increasing, especially towards wind and hydro powers, which should be efficiently converted into electric energy via suitable technology tools. To this end, data-driven control techniques represent viable strategies that can be employed for this purpose, due to the features of these nonlinear dynamic processes of working over a wide range of operating conditions, driven by stochastic inputs, excitations and disturbances. Therefore, the paper aims at providing some guidelines on the design and the application of different data-driven control strategies to a wind turbine benchmark and a hydroelectric simulator. They rely on self-tuning PID, fuzzy logic, adaptive and model predictive control methodologies. Some of the considered methods, such as fuzzy and adaptive controllers, were successfully verified on wind turbine systems, and similar advantages may thus derive from their appropriate implementation and application to hydroelectric plants. These issues represent the key features of the work, which provides some details of the implementation of the proposed control strategies to these energy conversion systems. The simulations will highlight that the fuzzy regulators are able to provide good tracking capabilities, which are outperformed by adaptive and model predictive control schemes. The working conditions of the considered processes will be also taken into account in order to highlight the reliability and robustness characteristics of the developed control strategies, especially interesting for remote and relatively inaccessible location of many plants. Full article
(This article belongs to the Special Issue Renewable Electric Energy Systems)
Figures

Graphical abstract

Open AccessArticle
Energy Selective Filter with Power-Dependent Transmission Effectiveness in Waveguide
Electronics 2019, 8(2), 236; https://doi.org/10.3390/electronics8020236
Received: 27 January 2019 / Revised: 15 February 2019 / Accepted: 18 February 2019 / Published: 20 February 2019
Cited by 1 | Viewed by 506 | PDF Full-text (15224 KB) | HTML Full-text | XML Full-text
Abstract
A novel Energy Selective Filter (ESF) mounted in waveguide is presented based on nonlinear element, which is sensitive to the power intensity of incident wave achieving frequency selection as well as energy selection. The proposed ESF consists of three parts, the middle circuit [...] Read more.
A novel Energy Selective Filter (ESF) mounted in waveguide is presented based on nonlinear element, which is sensitive to the power intensity of incident wave achieving frequency selection as well as energy selection. The proposed ESF consists of three parts, the middle circuit board with diode loaded, the upper and bottom ground metallic patches. The mechanism of the ESF is analyzed through equivalent circuit model and its performance is investigated numerically and experimentally. According to the waveguide measurement, a shielding effectiveness of 13 dB is achieved in case of high power input and the insertions loss is less than 0.3 dB across the whole frequency range when low power signal inputs. It is a pluggable component in waveguide that could reflect high power signals of specific frequency to protect the following electronic equipment. Full article
(This article belongs to the Section Microwave and Wireless Communications)
Figures

Figure 1

Open AccessArticle
Performance Analysis of Single-Step Localization Method Based on Matrix Eigen-Perturbation Theory with System Errors
Electronics 2019, 8(2), 235; https://doi.org/10.3390/electronics8020235
Received: 16 January 2019 / Revised: 5 February 2019 / Accepted: 11 February 2019 / Published: 19 February 2019
Viewed by 503 | PDF Full-text (2061 KB) | HTML Full-text | XML Full-text
Abstract
Direct position determination (DPD) is a novel technique in passive localization field recently, receiving superior localization performance compared with the conventional two-step method. The DPD estimator using Doppler shifts is first proposed by Weiss, but it is not suitable for antenna arrays. Additionally, [...] Read more.
Direct position determination (DPD) is a novel technique in passive localization field recently, receiving superior localization performance compared with the conventional two-step method. The DPD estimator using Doppler shifts is first proposed by Weiss, but it is not suitable for antenna arrays. Additionally, the performance analysis of this method with system errors is absent. This study discusses the single-step localization problem based on moving arrays and exhibits the performance analysis via matrix eigen-perturbation theory with system errors. First, the DPD method using angle of arrival and Doppler shifts is introduced. Then, by adding the eigenvalue perturbations to the estimated Hermitian matrix, the asymptotic linear formulation of localization errors is derived. Consequently, the mean square error of the DPD method is available. Finally, Cramér–Rao bound without system errors is presented, providing a benchmark for the best localization precision and revealing the influence of system errors on the localization precision. Simulation results demonstrate the theoretical analysis in this study. Full article
(This article belongs to the Special Issue Signal Processing and Analysis of Electrical Circuit)
Figures

Figure 1

Open AccessArticle
Simulation Model for Blockchain Systems Using Queuing Theory
Electronics 2019, 8(2), 234; https://doi.org/10.3390/electronics8020234
Received: 26 January 2019 / Revised: 10 February 2019 / Accepted: 13 February 2019 / Published: 19 February 2019
Cited by 2 | Viewed by 876 | PDF Full-text (3426 KB) | HTML Full-text | XML Full-text
Abstract
In recent years, blockchains have obtained so much attention from researchers, engineers, and institutions; and the implementation of blockchains has started to revive a large number of applications ranging from e-finance, e-healthcare, smart home, Internet of Things, social security, logistics and so forth. [...] Read more.
In recent years, blockchains have obtained so much attention from researchers, engineers, and institutions; and the implementation of blockchains has started to revive a large number of applications ranging from e-finance, e-healthcare, smart home, Internet of Things, social security, logistics and so forth. In the literature on blockchains, it is found that most articles focused on their engineering implementation, while little attention has been devoted to the exploration of theoretical aspects of the system; however, the existing work is limited to model the mining process only. In this paper, a queuing theory-based model is proposed for understanding the working and theoretical aspects of the blockchain. We validate our proposed model using the actual statistics of two popular cryptocurrencies, Bitcoin and Ethereum, by running simulations for two months of transactions. The obtained performance measures parameters such as the Number of Transactions per block, Mining Time of Each Block, System Throughput, Memorypool count, Waiting Time in Memorypool, Number of Unconfirmed Transactions in the Whole System, Total Number of Transactions, and Number of Generated Blocks; these values are compared with actual statistics. It was found that the results gained from our proposed model are in good agreement with actual statistics. Although the simulation in this paper presents the modeling of blockchain-based cryptocurrencies only, the proposed model can be used to represent a wide range of blockchain-based systems. Full article
(This article belongs to the Special Issue Distributed Computing and Storage)
Figures

Figure 1

Open AccessArticle
Camera-Based Blind Spot Detection with a General Purpose Lightweight Neural Network
Electronics 2019, 8(2), 233; https://doi.org/10.3390/electronics8020233
Received: 1 January 2019 / Revised: 1 February 2019 / Accepted: 13 February 2019 / Published: 19 February 2019
Cited by 2 | Viewed by 813 | PDF Full-text (3983 KB) | HTML Full-text | XML Full-text
Abstract
Blind spot detection is an important feature of Advanced Driver Assistance Systems (ADAS). In this paper, we provide a camera-based deep learning method that accurately detects other vehicles in the blind spot, replacing the traditional higher cost solution using radars. The recent breakthrough [...] Read more.
Blind spot detection is an important feature of Advanced Driver Assistance Systems (ADAS). In this paper, we provide a camera-based deep learning method that accurately detects other vehicles in the blind spot, replacing the traditional higher cost solution using radars. The recent breakthrough of deep learning algorithms shows extraordinary performance when applied to many computer vision tasks. Many new convolutional neural network (CNN) structures have been proposed and most of the networks are very deep in order to achieve the state-of-art performance when evaluated with benchmarks. However, blind spot detection, as a real-time embedded system application, requires high speed processing and low computational complexity. Hereby, we propose a novel method that transfers blind spot detection to an image classification task. Subsequently, a series of experiments are conducted to design an efficient neural network by comparing some of the latest deep learning models. Furthermore, we create a dataset with more than 10,000 labeled images using the blind spot view camera mounted on a test vehicle. Finally, we train the proposed deep learning model and evaluate its performance on the dataset. Full article
Figures

Graphical abstract

Open AccessArticle
Design of a Low-Cost PV Emulator Applied for PVECS
Electronics 2019, 8(2), 232; https://doi.org/10.3390/electronics8020232
Received: 17 January 2019 / Accepted: 14 February 2019 / Published: 19 February 2019
Viewed by 669 | PDF Full-text (3769 KB) | HTML Full-text | XML Full-text
Abstract
Applied tests on a real photovoltaic panel for a consolidated analysis require complex experiment setup and permanent availability of climatic conditions. This method is ineffective and can damage the PV system. As a result, PV emulators are highly requested in solar energy conversion [...] Read more.
Applied tests on a real photovoltaic panel for a consolidated analysis require complex experiment setup and permanent availability of climatic conditions. This method is ineffective and can damage the PV system. As a result, PV emulators are highly requested in solar energy conversion and generation research, which rests essentially on a maximum power point tracking control algorithm (MPPT) and an adapting power stage as the DC-DC converter and PV inverter. The PV emulator guarantees a controllable light source environment to act as a real PV system in the laboratory. This paper deals with the study and development of an experimental PV emulator based on logarithmic approximation of the ideal single diode model (ISDM), which is implemented using analog electronic components. Mainly, the PV model, the controller, and the power stages, forming the PV emulator, are described. This simple, low-cost, and efficient device is considered as a nonlinear power supply template replacing the real PV system for any operating point irrespective of the environmental condition changes. The emulated current-voltage and power-voltage curves are validated via resistive load and batteries. Then, the performance of the proposed PV emulator is evaluated by its ability to recharge properly two 12V 7 Ah batteries. Full article
(This article belongs to the Special Issue Grid Connected Photovoltaic Systems)
Figures

Figure 1

Open AccessArticle
Online Tuning of a PID Controller with a Fuzzy Reinforcement Learning MAS for Flow Rate Control of a Desalination Unit
Electronics 2019, 8(2), 231; https://doi.org/10.3390/electronics8020231
Received: 10 December 2018 / Revised: 9 February 2019 / Accepted: 14 February 2019 / Published: 18 February 2019
Cited by 1 | Viewed by 747 | PDF Full-text (6556 KB) | HTML Full-text | XML Full-text
Abstract
This paper proposes a hybrid Zeigler-Nichols (Z-N) fuzzy reinforcement learning MAS (Multi-Agent System) approach for online tuning of a Proportional Integral Derivative (PID) controller in order to control the flow rate of a desalination unit. The PID gains are set by the Z-N [...] Read more.
This paper proposes a hybrid Zeigler-Nichols (Z-N) fuzzy reinforcement learning MAS (Multi-Agent System) approach for online tuning of a Proportional Integral Derivative (PID) controller in order to control the flow rate of a desalination unit. The PID gains are set by the Z-N method and then are adapted online through the fuzzy Q-learning MAS. The fuzzy Q-learning is introduced in each agent in order to confront with the continuous state-action space. The global state of the MAS is defined by the value of the error and the derivative of error. The MAS consists of three agents and the output signal of each agent defines the percentage change of each gain. The increment or the reduction of each gain can be in the range of 0% to 100% of its initial value. The simulation results highlight the performance of the suggested hybrid control strategy through comparison with the conventional PID controller tuned by Z-N. Full article
(This article belongs to the Section Computer Science & Engineering)
Figures

Figure 1

Open AccessArticle
QoS-Based DWBA Algorithm for NG-EPON
Electronics 2019, 8(2), 230; https://doi.org/10.3390/electronics8020230
Received: 25 December 2018 / Revised: 9 February 2019 / Accepted: 14 February 2019 / Published: 18 February 2019
Cited by 1 | Viewed by 587 | PDF Full-text (593 KB) | HTML Full-text | XML Full-text
Abstract
The next-generation Ethernet passive optical network (NG-EPON) is basically classified into two architectures on the basis of the wavelength sharing by the optical network units (ONUs). The single scheduling domain (SSD) and multi-scheduling domain (MSD) EPON are the two different design architectures for [...] Read more.
The next-generation Ethernet passive optical network (NG-EPON) is basically classified into two architectures on the basis of the wavelength sharing by the optical network units (ONUs). The single scheduling domain (SSD) and multi-scheduling domain (MSD) EPON are the two different design architectures for NG-EPON. A vital task in NG-EPON is to design dynamic wavelength bandwidth allocation (DWBA) algorithms that can meet the future demands of the network subscribers. A number of DWBA algorithms have been designed for time and wavelength division multiplex (TWDM) EPON. The existing DWBA algorithms for TWDM-EPON could be used in MSD-EPON by making necessary parametric changes. The design and implementation of new DWBA algorithms for MSD-EPON are still required specifically. In this paper, we have proposed a quality of service (QoS)-based DWBA algorithm for NG-EPON. We have comparatively analyzed our proposed DWBA with the existing algorithms like earlier finished time (EFT), weighted bipartite matching (WBM), and earlier finished time with void filling (EFT-VF). The results show that our proposed DWBA algorithm performs better as compared to EFT, WBM, and EFT-VF on the basis of average packet delay and average completion time for NG-EPON. Full article
(This article belongs to the Special Issue Optical Communications and Networks)
Figures

Figure 1

Open AccessArticle
Pansharpening with a Gradient Domain GIF Based on NSST
Electronics 2019, 8(2), 229; https://doi.org/10.3390/electronics8020229
Received: 24 December 2018 / Revised: 13 February 2019 / Accepted: 15 February 2019 / Published: 18 February 2019
Viewed by 658 | PDF Full-text (8667 KB) | HTML Full-text | XML Full-text
Abstract
In order to improve the fusion quality of multispectral (MS) and panchromatic (PAN) images, a pansharpening method with a gradient domain guided image filter (GIF) that is based on non-subsampled shearlet transform (NSST) is proposed. First, multi-scale decomposition of MS and PAN images [...] Read more.
In order to improve the fusion quality of multispectral (MS) and panchromatic (PAN) images, a pansharpening method with a gradient domain guided image filter (GIF) that is based on non-subsampled shearlet transform (NSST) is proposed. First, multi-scale decomposition of MS and PAN images is performed by NSST. Second, different fusion rules are designed for high- and low-frequency coefficients. A fusion rule that is based on morphological filter-based intensity modulation (MFIM) technology is proposed for the low-frequency coefficients, and the edge refinement is carried out based on a gradient domain GIF to obtain the fused low-frequency coefficients. For the high-frequency coefficients, a fusion rule based on an improved pulse coupled neural network (PCNN) is adopted. The gradient domain GIF optimizes the firing map of the PCNN model, and then the fusion decision map is calculated to guide the fusion of the high-frequency coefficients. Finally, the fused high- and low-frequency coefficients are reconstructed with inverse NSST to obtain the fusion image. The proposed method was tested using the WorldView-2 and QuickBird data sets; the subjective visual effects and objective evaluation demonstrate that the proposed method is superior to the state-of-the-art pansharpening methods, and it can efficiently improve the spatial quality and spectral maintenance. Full article
(This article belongs to the Section Computer Science & Engineering)
Figures

Figure 1

Open AccessArticle
DSCBlocks: An Open-Source Platform for Learning Embedded Systems Based on Algorithm Visualizations and Digital Signal Controllers
Electronics 2019, 8(2), 228; https://doi.org/10.3390/electronics8020228
Received: 17 January 2019 / Accepted: 29 January 2019 / Published: 18 February 2019
Cited by 1 | Viewed by 1037 | PDF Full-text (18158 KB) | HTML Full-text | XML Full-text
Abstract
DSCBlocks is an open-source platform in hardware and software developed in JavaFX, which is focused on learning embedded systems through Digital Signal Controllers (DSCs). These devices are employed in industrial and educational sectors due to their robustness, number of peripherals, processing speed, scalability [...] Read more.
DSCBlocks is an open-source platform in hardware and software developed in JavaFX, which is focused on learning embedded systems through Digital Signal Controllers (DSCs). These devices are employed in industrial and educational sectors due to their robustness, number of peripherals, processing speed, scalability and versatility. The platform uses graphical blocks designed in Google’s tool Blockly that can be used to build different Algorithm Visualizations (AVs). Afterwards, the algorithms are converted in real-time to C language, according to the specifications of the compiler for the DSCs (XC16) and they can be downloaded in one of the two models of development board for the dsPIC 33FJ128GP804 and dsPIC 33FJ128MC802. The main aim of the platform is to provide a flexible environment, drawing on the educational advantages of the AVs with different aspects concerning the embedded systems, such as declaration of variables and functions, configuration of ports and peripherals, handling of Real-Time Operating System (RTOS), interrupts, among others, that are employed in several fields such as robotics, control, instrumentation, etc. In addition, some experiments that were designed in the platform are presented in the manuscript. The educational methodology and the assessment provided by the students (n = 30) suggest that the platform is suitable and reliable to learn concepts relating to embedded systems. Full article
Figures

Figure 1

Open AccessArticle
Voltage Multiplier Cell-Based Quasi-Switched Boost Inverter with Low Input Current Ripple
Electronics 2019, 8(2), 227; https://doi.org/10.3390/electronics8020227
Received: 21 January 2019 / Revised: 14 February 2019 / Accepted: 15 February 2019 / Published: 18 February 2019
Cited by 2 | Viewed by 702 | PDF Full-text (4328 KB) | HTML Full-text | XML Full-text
Abstract
A novel single-phase single-stage voltage multiplier cell-based quasi-switched boost inverter (VMC-qSBI) is proposed in this paper. By adding the voltage multiplier cell to the qSBI, the proposed VMC-qSBI has the following merits; a decreased voltage stress on an additional switch, a high voltage [...] Read more.
A novel single-phase single-stage voltage multiplier cell-based quasi-switched boost inverter (VMC-qSBI) is proposed in this paper. By adding the voltage multiplier cell to the qSBI, the proposed VMC-qSBI has the following merits; a decreased voltage stress on an additional switch, a high voltage gain, a continuous input current, shoot through immunity, and a high modulation index. A new pulse-width modulation (PWM) control strategy is presented for the proposed inverter to reduce the input current ripple. To improve the voltage gain of the proposed inverter, an extension is addressed by adding the VMCs. The operating principle, steady-state analysis, and impedance parameter design guideline of the proposed inverter are presented. A comparison between the proposed inverter and other impedance source-based high-voltage gain inverters is shown. Simulation and experimental results are provided to confirm the theoretical analysis. Full article
(This article belongs to the Special Issue Power Converters in Power Electronics)
Figures

Figure 1

Open AccessArticle
LS-Solar-PV System Impact on Line Protection
Electronics 2019, 8(2), 226; https://doi.org/10.3390/electronics8020226
Received: 29 January 2019 / Revised: 14 February 2019 / Accepted: 15 February 2019 / Published: 18 February 2019
Cited by 2 | Viewed by 740 | PDF Full-text (3904 KB) | HTML Full-text | XML Full-text
Abstract
Large-scale photovoltaic power station access to the grid will profoundly change the fault current characteristics of the power station’s outgoing lines. This change results in adaptive problems in traditional protection phase selection components, which may cause incorrect actions in reclosing, protection ranging, and [...] Read more.
Large-scale photovoltaic power station access to the grid will profoundly change the fault current characteristics of the power station’s outgoing lines. This change results in adaptive problems in traditional protection phase selection components, which may cause incorrect actions in reclosing, protection ranging, and distance protection. Based on the fault current characteristics of the large-scale photovoltaic power station transmission line, this paper analyzes the adaptability of the phase current difference mutation and the sequence component phase selection component in protecting the Photovoltaic (PV) power plant side of the transmission line. Based on the fault current analytical formula, the phase relationship between the phase current difference and the current sequence component under different control targets, such as suppressing negative sequence current, suppressing the active power fluctuation, and suppressing the reactive power fluctuation, is derived. The operational performances of the phase–phase current difference of the abrupt phase selection component and the sequence component phase selection component of the power station side are degraded, which may cause incorrect operation of the phase selection component. Based on the actual engineering parameters of a PV power plant, a simulation model was built in Power System Computer Aided Design (PSCAD) to verify the correctness of the theoretical analysis. Full article
(This article belongs to the Special Issue Grid Connected Photovoltaic Systems)
Figures

Figure 1

Electronics EISSN 2079-9292 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top