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In this work, we aim to show that there are generally four possible mapping functions that can be used to map the time-domain or frequency-domain representations of an applied voltage input to the resulting time-domain or frequency-domain electrical charge output; i.e. when the capacitive device is voltage-charged. Alternatively, there are four more possible combinations when the device is current-charged. The dual relationship between each pair of functions for the case of voltage or charge input are provided in terms of single or double Fourier transforms. All eight system functions coincide with each other if and only if a constant time- and frequency-independent capacitance is considered.

Now adays Very Large-Scale Integration (VLSI) circuits have good or great demand. Because CMOS circuit design having less power consumption. Transistors on the chip is doubled every two years, according to Moore’s law. So, it means transistor size is decreasing. This leads to increase the chip density and decrease the device size. The write and read depending on the bitline and bitline bar discharging and charging. When design the memory in below 16 nm uses Fin Field effect Transistor (FinFET) technology instead of CMOS (Complementary metal oxide semiconductor field effect transistor). Because to avoid short channel effect. Comparing leakage power, dynamic power and static power at 90 nm technology and write delay, read delay at both 90 nm and 45 nm technology in nine transistors (9 t), eight transistor (8 t) and six transistor (6 t) sram cell.

This paper presents, a three-phase grid interfaced charging station (CS) for electrical vehicle (EV). It interacts with the grid to compensate for the reactive power. The charging station operates in various modes (i) charging/discharging of EV battery, (ii) compensation of reactive power (iii) both concurrent charging and compensation of harmonics current and (iv) concurrent discharging and compensation of harmonics current. The CS while in grid connected mode, operates under distorted and unbalance grid conditions. The control of the charging station is designed such that the reference grid currents synchronize with the phase voltages at PCC (Point of Common Coupling). If the grid losses synchronism then the charging station works in islanded mode and PV source charges the EV battery. The performance of the charging station is tested under various dynamic conditions and the grid currents distortion levels are in the limits as recommended by the standard IEEE-519.

This paper addresses optimal battery thermal management (BTM), charging, and eco-driving of a battery electric vehicle (BEV) with the goal of improving its grid-to-meter energy efficiency. Thus, an optimisation problem is formulated, aiming at finding the optimal trade-off between trip time and charging cost. The formulated problem is then transformed into a hybrid dynamical system, where the dynamics in driving and charging modes are modeled with different functions and with different state and control vectors. Moreover, to improve computational efficiency, we propose modelling the driving dynamics in a spatial domain, where decisions are made along the traveled distance. Charging dynamics are modeled in a temporal domain, where decisions are made along a normalized charging time. The actual charging time is modeled as a scalar variable that is optimized simultaneously with the optimal state and control trajectories, for both charging and driving modes. The performance of the proposed algorithm is assessed over a road with a hilly terrain, where two charging possibilities are considered along the driving route. According to the results, trip time including driving and charging times, is reduced by 44 %, compared to a case without battery active heating/cooling.

This paper investigates a single-phase multilevel dc-ac converter composed of four series/parallel-connected H-bridges with floating capacitors. System model, pulse-width modulation (PWM) strategies, and a control strategy have been presented. An important variable is the control of the dc-links voltages in the floating capacitor. Thus, an individual balancing of dc-links voltages using auxiliary variables and redundant voltage vectors are shown in this work for different dc-link voltage ratios. Simulations and experimental results with several power levels show how the operating characteristics.

The paper proposes an integrated power converter (IPC) with driving/charging capabilities for 4-phase switched reluctance motor (SRM) drive based electric vehicle (EV) application. With the proposed IPC, only two current sensors are employed for measuring phase currents under all operating conditions. The proposed IPC integrates three circuits. Firstly, during the SRM driving mode, the proposed IPC is utilized as an improved miller converter. Secondly, during battery charging mode, the proposed IPC is utilized as an on-board battery charger which is based on a bridgeless boost power factor correction circuit (PFCC) that incorporates two DC-DC boost converters. The on-board battery charger is realized by utilizing the existing power electronic switches in the proposed IPC and all the phase windings as charging inductors. Third, a front-end bidirectional DC-DC converter for maintaining voltage and current balance between IPC DC-bus and battery. During driving mode, the front-end converter boosts the battery voltage to the IPC DC bus voltage. And during regeneration/braking, the stored magnetic energy is used to charge the battery in constant-current (CC) mode via the front-end converter. During battery charging via AC grid, the bridgeless boost PFCC and the front-end converter operating in buck mode charges the battery in CC/ constant-voltage (CV) modes without stepping down the AC grid voltage. The claims of the proposed IPC are validated through simulation and experimental verifications.

In a Wireless Rechargeable Sensor Network (WRSN), a mobile charger (MC) moves and supplies energy for sensor nodes to maintain the network operation. Hence, optimizing the charging schedule of MC is essential to maximize the network lifetime in WRSNs. The existing works only target the local optimization of network lifetime limited to MC’s subsequent charging round. The network lifetime has been normally reflected in a different metric that is not directly related to the final charging round period. To the best of our knowledge, this work is the first to address the global maximization of network lifetime in WRSNs, which optimizes not only the subsequent charging round but all charging rounds over the entire network lifetime. Another uniqueness is the joint consideration of both the charging path and charging time optimization problems. As a solution, we propose a genetic algorithm (GA)-based global optimization scheme that considers all the possible charging rounds. The GA has a novel mutation operation that mutates gene sizes for representing charging schedules with a varying number of charging rounds. The experiment results show that our algorithm can extend the network lifetime by 35.1 times on average and 38.6 times in the best case compared to existing ones.

This paper introduces a new coupled inductor based dual-input ultra-high step-up DC-DC converter with a high voltage conversion ratio, low voltage stress across semiconductor components, and high efficiency features. The coupled inductor and voltage multiplier circuit (VMC) techniques have been utilized to enhance the voltage gain. The blocking voltages of power switches are clamped by VMC at low values and can be controlled via the turn ratio of the coupled inductors that decreases the voltage rate of power switches and converters cost. The presented dual-input structure can transfer power to the load from two independent voltage sources. Also, the inputs and output ports are common ground, which can reduce the electromagnetic interference (EMI) influences. Operation modes delineation, steady-state analysis, and comparison section are provided for describing the proposed structure performance. Finally, to confirm the effectiveness of the presented topology, experimental waveforms with a 200 W output power at 50 kHz operating frequency are presented.

Non-isolated high-voltage gain soft-switching dc-dc converter is an ideal candidate for distributed generation system converters. This paper proposes a high-voltage gain soft switching quasi-Z-source dc-dc converter. The converter integrates a coupled inductor and switched capacitor into a quasi-Z-source network. Soft switching is achieved for all active devices in the converter by controlling the auxiliary switch Sa. By inheriting the advantages of the quasi-Z-source network and coupled-inductor/switched-capacitor, the converter has high voltage gain, high efficiency, low input current ripple, low voltage spike of main switch, and common ground. In addition, the efficiency of the converter is improved by recycling the energy of leakage inductance, resulting from an inherent active clamp of the main switch. The steady-state operation, voltage relationship, current/voltage stress, and power dissipation of each component of the converter have been analyzed and derived in detail. The properties of the proposed converter are verified by designing a 200 W prototype in the laboratory. When the input voltage is 48 V and the output voltage is 380 V, the converter efficiency reaches 96.92%, while the efficiency is 93% in a hard switching. The key waveforms of the converter obtained from the experiment agree well with the theoretical analysis results.

High voltage/high power capacitor chargers are primarily interested in many industrial applications. Resonant converters have been a proper choice in such applications because of their advantages. However, the performance of the resonant converter is highly affected by the parasitic elements of the high voltage/high power transformer. Also, short circuit condition is a frequent event in high voltage applications, so that the resonant converter should be robust against the short circuit condition. This paper presents a novel LCCL resonant converter with current source characteristics used as a high voltage capacitor charger. The proposed resonant converter eliminates the undesirable effect of the stray capacitance in high voltage devices and is robust against the short circuit condition inherently. It also provides a semi-trapezoidal resonant current wave which produces a lower crest factor. Furthermore, a frequency-sweep operation is applied, which has advantages in reducing the resonant current's peak value and the resonant network's size. Simulation results show a satisfactory performance of the proposed resonant converter. Moreover, experimental results confirm the effectiveness of the proposed resonant converter in the application of capacitor charging.

This paper investigates the origin of the flying capacitor voltage imbalance in hybrid converters. By observation and logical deduction, an intuitive voltage-charge relationship is established which can give a general explanation of the flying capacitor voltage balance in hybrid converters. This relationship can establish a relatively simple and intuitive method to identify the difference of balance performance in hybrid converters for Voutin /N) cases. Converter with even number of inductor charging intervals, are shown to be susceptible to flying capacitor voltage imbalance, while flying capacitors in hybrid converters with inductors having odd charging intervals have inherently balanced operations. As a direct result of the analysis, a new symmetric operation of FCML converters is introduced to achieve an inherent balance of flying capacitor voltages. Hardware implementations and experiments have been carried out for verifications of the analytical analysis and the new symmetric operation.

This paper proposes a high step-up dc-dc converter with a continuous input current which is suitable for sustainable energy systems. A three-winding coupled inductor, two power switches, three diodes, and three capacitors are utilized to perform the functions of active switched inductor and switched capacitor. By charging the two primary windings in parallel, and discharging the two primary windings in series to the intermediate capacitor and the output, the conversion ratio can be further improved with lower voltage stresses and current stresses on its power switches. In addition, the energy stored in the leakage inductance is recycled to reduce the voltage spikes of the power switches. Eventually, a laboratory prototype with an input voltage of 36 V - 48 V, and output voltage of 400 V - 600 V with a rated power of 600 W is implemented to validate the correctness and effectiveness of the theoretical analyses. The maximum efficiency and full load efficiency are 97 % and 96.2 %, respectively.

Electrification of bus fleets in most cities is expected to rise due to its significant environmental benefits. However, electric buses have limited driving range and long recharging times. Additionally, electric buses require special charging infrastructure, which overall makes them less flexible than conventional diesel buses. Due to the limitations of the electric bus technologies, further adjustments have to be made to the current bus transport planning problems. The scheduling of electric vehicles is recognized as a fast-growing area of research. In this paper, we review 43 articles related to the electric bus technologies and give an overview of the different problems in the electric bus planning process (strategic, tactical and operational). The different problems are: 1) investment of electric bus fleet and charging infrastructure, 2) placement of charging infrastructure, 3) the electric vehicle scheduling problem (E-VSP) and 4) the charging scheduling problem. Given a set of timetabled trips and recharging stations, the E-VSP is concerned with finding a vehicle schedule that covers the trips and satisfies the driving range and recharging requirements of electric buses while minimizing operational cost. A detailed literature review of the constraints associated with the E-VSP and the solution approaches proposed to solve it is given. Rescheduling aspects or considerations of robustness for scheduling of electric vehicles is identified as a future area of research. Furthermore, integrated electric bus planning is considered as a crucial area of research and integrated approaches could further improve the efficiency of electric bus transport systems.

Wireless recharging using a mobile charger has been widely discussed in recent years. Most of them considered that all sensors were equally important and aimed to maximize the number of recharged sensors. The purpose of energy recharging is to extend the lifetime of sensors whose major work is to maximize the surveillance quality. In a randomly deployed wireless rechargeable sensor network, the surveillance quality highly depends on the contributions of coverage and network connectivity of each sensor. Instead of considering maximizing the number of recharged sensors, this article further takes into consideration the contributions of coverage and network connectivity of each sensor when making the decision of recharging schedule, aiming to maximize the surveillance quality and improve the number of data collected from sensors to the sink node. This article proposes an energy recharging mechanism, called an energy recharging mechanism for maximizing the surveillance quality of a given WRSNs (ERSQ), which partitions the monitoring region into several equal-sized grids and considers the important factors, including coverage contribution, network connectivity contribution, the remaining energy as well as the path length cost of each grid, aiming to maximize surveillance quality for a given wireless sensor network. Performance studies reveal that the proposed ERSQ outperforms existing recharging mechanisms in terms of the coverage, the number of working sensors as well as the effectiveness index of working sensors.

Problem definition: By providing an environmentally friendly alternative to traditional vehicles, electric vehicles will transform urban mobility, particularly in smart cities. In practice, after an electric vehicle is plugged in, the charging station completes charging as soon as possible. Given that the procurement cost of electricity and associated emissions vary significantly during a day, substantial savings can be achieved by smart charging—delaying charging until the cost is lower. In this paper, we study smart charging as an innovative business model for utility firms. Academic/practical relevance: Utility firms are already investing in charging stations, and they can achieve significant cost savings through smart charging. Methodology: We consider a mechanism design problem in which a utility firm first announces pairs of charging price and completion time. Then, each customer selects the pair that maximizes their utility. Given the selected completion times, the utility firm solves the optimal control problem of determining the charging schedule that minimizes the cost of charging under endogenous, time-varying electricity procurement cost. We assume that there are ample parking spots with chargers at the charging station. Results: We devise an intuitive and practically implementable policy for scheduling charging of electric vehicles under given completion times. We prove that this policy is optimal if all customers arrive at the station simultaneously. We also characterize the optimal pairs of charging price and completion time. By using real electricity demand and generation data from the largest electricity market in the United States, we find that cost and emissions savings from smart charging are approximately 20% and 15%, respectively, during a typical summer month. Managerial implications: In contrast to the current practice of charging vehicles without delay, we show that it is economically and environmentally beneficial to delay charging some vehicles and to set charging prices based on customers’ inconvenience cost of delays. We also find that most of the savings from implementing smart charging can be achieved during peak-demand days, highlighting the effectiveness of smart charging.

Micro-electro-mechanical systems reveals excellent versatility and malleability in miniaturization device with having a compacted aspect, less usage of energy, as well as performing up to the mark. MEMS systems have multiple and significant potential to create a novel ground of mobile equipment uses with enhanced flexible and enhanced reliable aspect. Current study deals with investigations conducted to develop actuator and sensor bases on MEMS and MEMS-based applications. At a lower cost than ever before, the current trend in micro / Nano systems is to fabricate smaller, lighter and more powerful devices. Continued advancements in MEMS technology have resulted in a multitude of previously impossible new devices being created. Nevertheless, these devices ' implementations are limited by their integration and packaging problems. Considering design and fabrication issues, a review on the MEMS future and the significant importance of those material in future is illustrated. We will address some of these issues in MEMS technology in this study.

A three-level bidirectional AC-DC converter with H8 topology is proposed to combine the advantages of both neutral-point clamped and flying-capacitor three-level converters for medium voltage AC-DC solid-state transformer applications. The innovative H8 converter features self-balanced capacitor voltage, common-mode voltage elimination, and small capacitance of the flying capacitors. The proposed carrier-based modulation enables the H8 converter to operate under both active and reactive power conditions. A 10 kVA AC-DC converter prototype with 1.7 kV SiC MOSFETs and 3.3 kV SiC diodes verifies the feasibility and advantages of the proposed topology and the modulation method. The capacitance of the flying capacitors in the H8 converter is reduced by 45 times compared to that of the flying-capacitor converters. The H8 converter efficiency is tested up to 99% at 2 kV DC voltage. The proposed H8 converter is suitable for the next-generation PV inverter, grid-forming inverter, MV fast charger, and SST applications.

Recently, with the developing environmental awareness, electric vehicles are increasing even more. For this reason, different searches have emerged to solve the problems related to meeting the energy needs of electric vehicles and charging their batteries quickly and reliably. One of these ideas is wireless power transfer (WPT) battery charging systems, which researchers have focused on for the past two decades. In this study, a wireless charging station that can be used to charge the batteries of electric vehicles is designed and examined by applying it to a prototype vehicle. Also, it is examined that the designed system can be adapted with renewable energy sources (such as solar energy) independently of a local energy source. It is aimed with the WPT prototype to realize a more efficient system for the 10 W power level and 86 kHz. The electromagnetic modelling of WPT is designed using ANSYS-Electronics/Maxwell software. Ultimately, the power electronics circuit performance of this system was analyzed with ANSYS Electronics / Simplorer software for co-simulation.

In order to locate the leakage fault location of low-voltage electrical lines, cut off the power supply of electrical lines, and ensure the safety and reliability of the power supply network, this paper proposes an electrical line leakage fault detection system based on a signal trigger. Based on the research on the current leakage protection system of low-voltage electrical lines, the author puts forward that the leakage current of the selected test analog trigger signal is not less than twice the maximum value of the normal leakage current of electrical lines and equipment with STC15F2K60S2 single-chip microcomputer as the control core. The experimental results show that 30 mA is preferred for the sensitivity of the leakage fault test signal. When the rated leakage action current is equal to or less than 30 mA, the protection action time is required to be less than 0.1 s, and when the rated leakage action current is greater than 30 mA, it is required to be less than 0.2 S. The device is a supplement to the traditional leakage protection device. According to the comparison between the indirect leakage detection and direct leakage detection results and the actual leakage position distance, the error is within 10%. It is proved that the system meets the actual needs and improves the protection performance of the leakage protection system of low-voltage electrical lines.

The location planning of electric vehicles charging stations and battery-swapping stations needs to consider many factors, and the location decision is often a multi-objective management planning problem. This paper is based on the location planning of charging stations and battery-swapping stations, and considers the behavioral ability of users. The impact of the location and layout of charging stations and battery-swapping stations is to minimize the total cost, maximize user satisfaction, and minimize the electric energy consumed by electric vehicles on the way to stations. A planning model for the site selection of charging and battery-swapping stations based on multi-objective management planning. Then use the YALMIP/CPLEX method to solve the problem, dynamically analyze the relationship between the key parameters and the results, and finally obtain the optimal location planning and management layout of stations through a calculation example. It provides a certain reference for the location planning of urban electric vehicle charging stations and battery-swapping stations.

This paper proposes a coupled-inductor-based soft switching non-inverting Buck-Boost Converter (NIBBC) with reduced auxiliary component count. Instead of using multiple auxiliary passive components to achieve soft switching, the proposed coupled-inductor-based NIBBC uses the coupled inductor as the main inductor, and the auxiliary current generated by the magnetic coupling effect is used to obtain the soft switching for all switches. With simple PWM modulation under fixed frequency, full load range ZVS can be obtained under wide voltage range. Unlike the conventional method utilizing the coupled inductor only to generate non-active power, the coupled inductor of the proposed converter also takes participant in the power transmission. Besides, the added diode can achieve zero current turn-off which avoids the diode recovery issue. The operating principle, the soft switching and parameter designs are analyzed in this paper. Finally, experimental results have verified the effectiveness of the proposed solution.

Ferroelectric field-effect transistor-based circuit implementation mimicking FitzHugh-Nagumo neuron is proposed in this work. The proposed circuit is shown to mimic biological neuron properties such as excitation block and anodal break excitation which are not mimicked by an integrate and fire neuron model. We also show a winner-take-all circuit that can be used with this proposed neuron implementation. The neuron implementation requires just one ferroelectric field-effect transistor, three baseline field-effect transistors, and one capacitor, making it area and energy-efficient. The neuron circuit, with minimum sized transistors, consumes approximately 10pJ per spike. The neuron’s energy consumption per spike can be reduced to as low as 100fJ by designing some of the transistors with aspect ratio less than one.

The use of the millimeter wave (mmWave) spectrum and further exploration of sub-mmWave has led to a new era in wireless communication, as the need for higher data rates grows. High frequencies, on the other hand, incur a higher path loss, requiring an increase in antenna gain requirements. Metasurfaces, which emerge as a promising technology for mitigating path loss effects by utilizing two dimensional (2D) arrays of engineered meta-atoms resembling metamaterials that control the surface’s electromagnetic response have been introduced. Currently, metasurfaces are primarily considered as passive reflecting devices in wireless communications, assisting conventional transceivers in shaping propagation environments. This paper presents an alternative application of metasurfaces for wireless communications as active reconfigurable antennas for next generation transceivers. A framework that demonstrates the design process of a metasurface antenna structure was introduced and further used to design a 4 × 4 array and its reconfigurable counterpart. In contrast to conventional phased array antennas, a reconfigurable metasurface (RMS) antenna does not require phase-shifters and amplifiers, which leads to reduced cost. Instead, each individual element achieves reconfigurability by shifting the resonating frequency using semiconductor devices such as PIN diodes. The proposed metasurface antenna is designed to operate at a frequency of 28 GHz and 40 GHz. In addition, an increase in gain and directivity was observed when diodes were added to the metasurface antenna array. However, due to PIN diodes being connected to metallic strips in the metasurface antenna array, loss can occur due to power dissipation, which results in a decrease in radiation efficiency.

An interleaved high step-up converter topology based on the coupled inductor (CI) and built-in transformer (BIT) is proposed in this study to provide high step-up voltage gain and high efficiency with a low number of power electronic components for renewable energy applications. The voltage gain is increased by both of the turns’ ratio of CI and BIT, so there is no need to extend duty ratio to obtain high voltage gain. The proposed topology is much more flexible than those with only either CI or BIT. Moreover, the voltage stress across semiconductor devices can be relatively decreased by adjusting the turns’ ratio of the CI and BIT. In addition, the input current ripple can be reduced when the interleaved structure is applied at the input of this converter. Furthermore, turned-OFF and turned-ON zero current switching (ZCS) conditions for the diodes and power MOSFETs are achieved, respectively, thanks to the leakage inductances of the magnetic devices. Hence, due to the control of the falling current rate of the diodes by the leakage inductances, reverse recovery problem is alleviated. Moreover, the energy of the leakage inductances is recycled by the clamp capacitors avoiding high spikes across MOSFETs. As a result, according to the abovementioned advantages of the proposed converter, MOSFETs with low ON-state resistance and diodes with low forward voltage drop can be used to decrease the conduction losses. A 600 W laboratory prototype with 27–400 V voltage conversion at switching frequency 50 kHz is built to verify the performance of the proposed converter. Experimental results confirm the theoretical analysis. The efficiency reaches to 94.6% at full load which is close to the calculated of 95.8%.

In this paper, an ultrahigh step-up DC-DC converter is proposed with combination of a quadratic boost converter, a coupled inductor and a multiplier cell which doubles output voltage. Secondary side of the coupled inductor is unified with the multiplier cell. In addition, leakage energy of the coupled inductor is recycled and transferred to output perfectly which causes high efficiency performance. Main advantages of the converter include its high voltage gain, low voltage stress on its semiconductors and requiring smaller inductor in low voltage side of the converter. Power losses of the inductors are low due to current sharing between the input inductor and the coupled inductor. Continuity of input current and existence of a common ground between the load and source make the converter suitable for different applications. The converter is compared with the other converters based on analysis of its operation modes. Validity of the analysis and the converter performance are experimented using a 150W prototype that converters 20V from input side to 400V in output.

Accurate electric energy metering in micro-grid is one of the most urgent problems in the field of electric energy metering. In order to solve the problem that the lackness of electric energy metering can't be accurately calculated with the existing electric energy compensation algorithm when the electric energy metering device is completely faulty, this paper proposes an electric energy compensation algorithm that is limited in micro-grid and is based on standard particle swarm to optimize the deep belief network. Taking the historical electric energy data of each micro source metering point in micro-grid as an example, it is divided into the training set and the test set, the standard particle swarm optimization algorithm is used to determine the optimal learning layers and learning rate of deep belief network, and the electric energy algorithm model is established. The model verification results show that the proposed algorithm is nearly five times lower than the algorithm based on deep belief network solely. Further engineering case comparison shows that lackness of electric energy metering compensated by the algorithm studied in the paper is closer to the theoretical value, and the error is also less than the traditional average electricity algorithm. The real-time power curve is closer to the theoretical value, and has the higher accuracy.

This work presents a unique approach to the design, fabrication, and characterization of paper-based origami robotic systems consisting of stackable pneumatic actuators. These paper-based actuators (PBAs) use materials with high elastic modulus-to-mass ratios, accordion-like structures, and direct coupling with pneumatic pressure for extension and bending. The study contributes to the scientific and engineering understanding of foldable components under applied pneumatic pressure by constructing stretchable and flexible structures with intrinsically nonstretchable materials. Experiments showed that a PBA possesses a power-to-mass ratio greater than 80 W/kg, which is more than four times that of human muscle. This work also illustrates the stackability and functionality of PBAs by two prototypes: a parallel manipulator and a legged locomotor. The manipulator consisting of an array of PBAs can bend in a specific direction with the corresponding actuator inflated. In addition, the stacked actuators in the manipulator can rotate in opposite directions to compensate for relative rotation at the ends of each actuator to work in parallel and manipulate the platform. The locomotor rotates the PBAs to apply and release contact between the feet and the ground. Furthermore, a numerical model developed in this work predicts the mechanical performance of these inflatable actuators as a function of dimensional specifications and folding patterns. Overall, we use stacked origami actuators to implement functionalities of manipulation, gripping, and locomotion as conventional robotic systems. Future origami robots made of paper-like materials may be suitable for single use in contaminated or unstructured environments or low-cost educational materials.

We demonstrate a successful process scheme for the integration of a CMOS-compatible ferroelectric gate stack on a scaled vertical InAs nanowire gate-all-around MOSFET on silicon. The devices show promising device characteristics with nanosecond write time and large memory window of >1.5 V. In the current implementation, the device performance is mainly limited by access resistance, which is attributed to the thermal sensitivity of InAs. The findings indicate that the ferroelectricity is not intrinsically preventing future improvements of scaled III-V FeFETs.

This paper proposes a new bidirectional isolated LLC resonant converter, which is suitable for ultra-wide voltage gain range applications, such as electric vehicle charging systems. The inverter and rectifier of proposed topology both have two modes by reconfiguring different modulation schemes during bidirectional operation. This results in three voltage-gain ranges, allowing ultra-wide output voltage operation and narrow modulation frequency. The conversion ratio and resonant tank can be designed for only a quarter of the required output voltage range. Finally, the proposed topology and analysis are validated by experiments results obtained from the converter prototype built in the laboratory

Liquid leakage can cause industrial accidents. Current liquid leakage detection methods judge the leakage state by analyzing signals from special intrusion sensors, which is not ideal for early leakage due to sensor limited sensitivity. Visual information from surveillance systems deployed in industrial environments can reflect early leakage that cannot be monitored by such pressure sensors. In this paper, we propose a visual early leakage detection system based on a visual background extractor (Vibe) and EfficientNetB0. First, we extract the translucent and small potential leakage candidates based on Vibe, which include leakage targets and environmental interference. Then, to further recognize leakage targets in potential leakage candidates, we explore CNN models and a few recently proposed methods, and compare them with two different evaluation criteria. Our model based on EfficientNetB0 performs best and achieves 99.526% accuracy. Additionally, our CNN model for leakage recognition with a smaller size is feasible for industrial application. Experiments are conducted on the leakage dataset from surveillance video from the Tianjin Binhai Heating Station, and the detection results are consistent with real leakage situations. Our leakage detection system has high sensitivity and accuracy, which meets the requirements of early leakage detection.

Wireless rechargeable sensor networks (WRSNs) have emerged as a potential solution to solve the challenge of prolonging battery-powered sensor networks’ lifetime. In a WRSN, a mobile charger moves around and charges the rechargeable sensors when stopping at charging spots. This paper newly considers a joint optimization of the charging location and the charging time to avoid node failure in WRSNs. We formulate the optimization and propose a solution for that. The proposal includes an algorithm to find a list of potential charging locations and their associated optimal charging time. Moreover, the Q-learning technique is adopted to determine the optimal next charging location among the candidates. We implement the algorithm and conduct experiments to compare it to the related works. The results show that the proposed algorithm outperforms the others in terms of network lifetime. Specifically, the highest performance gap of our proposal to the best algorithm among the others is 8.29 times.

This paper illustrates an algorithm to balance the voltages across the DC-link capacitors of a three-level multiphase inverter feeding a star-connected load with an odd number of phases. The proposed strategy keeps the DC-link capacitors balanced in any operating condition and minimizes the low-frequency voltage oscillations, even during open-phase faults and with non-sinusoidal output currents. Finally, the paper identifies the operating region where the voltage oscillations of the DC-link capacitors can be canceled. The developed algorithm can maintain constant voltages even if the capacitors are unbalanced, and its performance is compared to that of other carrier-based algorithms. Experimental tests are carried out on a five-phase induction motor in healthy and faulty conditions.

The battery backup plays an important role in storing energy from the solar panel during the daytime. This energy, thus, stored can be utilized for daily usage during day and night. Depending on the amount of power generated from the solar panel the battery bank must be selected. The lifespan of the battery depends on the charging and discharging cycles. The life span also depends on the amount of load connected to the battery as well as the rate at which the current is drained from the battery. It’s critical to note the charging and discharging cycles of the battery must be reduced to improve the life span of the same. This paper explains the different types of batteries and the factors affecting the life span of batteries. The paper also suggests the methods to be followed to improve the life span by proposing a model for charging. This model regulates the charging and discharging cycle of a battery to increase the life span of the battery. The model also regulates the charging current by considering the battery temperature. The raise in battery temperature also reduces battery life. The paper performs the ABCD analysis of the new model considering the various issues related to battery performance and socio economic impacts of the same. This paper concludes with the recommendation to implement the charger for the battery-operated devices that do not require fast charging, thus, improving battery life. This paper also concludes with the statement that the proposed model is not suitable for any battery operated devices, which require fast charging where improved battery life is not so essential.

DEVSIM TCAD Semiconductor Device Simulator Documentation

The energy problem and limited capacity of batteries have been fundamental constraints in many wireless sensor network (WSN) applications. For WSN, the wireless energy transmission technology based on magnetic resonance coupling is a promising energy transmission technology. To reduce the cost and energy consumption during charging in mobile wireless rechargeable sensor networks (MWRSNs), a cooperative mobile charging mechanism based on the Hamiltonian path is proposed in this paper. To improve the charging task interval, we study the use of a mobile charger (MC) as a mobile sink node to collect the data in this paper. Then, we used the sink and the charging sensors selected by the MC to construct the undirected complete graph. Finally, the Euclidean distance between nodes is used as the edge weight and a Hamiltonian loop is found by using the improved Clark–Wright (C-W) saving algorithm to solve the problem of charging a rechargeable sensor network. In addition to the energy usage efficiency (EUE) and the network lifetime, the average energy loss per unit time is considered as the evaluation index according to the impact of the MC on the energy consumption during charging. The simulation results show that the proposed scheme increases the average network lifetime, decreases the average energy loss per unit time, and improves the EUE.

In this paper, a new antenna system for rapidly emerging multifunction devices is presented. The proposed antenna system consists of four antenna components each one operating at different frequency bands separately. The designed antennas are isolated and integrated on a single substrate. The first antenna is designed to operate at 1920–2170 MHz covering the UMTS band, whereas the second antenna is proposed for the lower band 5G systems and WiMAX operating within the frequency range of 3.4–4.2 GHz. Furthermore, another antenna is designed to cover the higher band 5G system and the IEEE 820.11a WLAN within the frequency range of 5.1–5.85 GHz. Finally, a 28 GHz bowtie-based MIMO antenna array is designed and simulated for the mmWave future 5G mobile networks. The proposed antennas were designed and simulated by using CST microwave studio. The results showed that all of the proposed antennas exhibited excellent reflection characteristics below −20 dB at the resonant frequency and achieved high radiation efficiency reached 99% in some cases with a peak gain ranging between 4–6 dBi. The proposed antenna system helps smartphones to perform multitasks and achieve a better-quality operation especially with the enormous growth of IoT techniques.

As a new type of urban rail transit tram, wireless charging tram uses high frequency electromagnetic field to conduct inductive power transmission, which gets rid of the traditional overhead catenary network, but inevitably causes electromagnetic radiation to the surrounding environment. Research shows that excessive electromagnetic radiation will affect the normal operation of equipment and the safety of human body. This paper analyzes the structure and coil configuration of the dynamic charging system for wireless charging tram. Aiming at the problem of electromagnetic radiation, a mathematical model with minimum electromagnetic radiation as the target and system parameters as the constraint condition is established. Finally, the system parameters of the electromagnetic coupling mechanism of the wireless charging tram are designed and optimized. The simulation and experimental results show that the method can meet the operating requirements of the system and reduce the electromagnetic radiation to the surrounding environment.

In battery swapping environments, electric vehicles (EVs) can play roles as battery providers as well as consumers. In this paper, we propose an optimal battery charging algorithm (OBCA) where a battery swapping station (BSS) charges batteries in its storage with the consideration of the profile of the electricity price and the arrival rates of EVs. To maximize the net profit of BSS while maintaining the battery changing probability above a certain level (i.e., maintaining high quality of service (QoS) of BSS), we formulate a constraint Markov decision process (CMDP) problem and the optimal charging schedule for batteries in BSS is obtained by a linear programming (LP). Evaluation results demonstrate that OBCA with the optimal policy can improve the net profit of BSS up to 418% compared to an electric price-aware scheme while maintaining high QoS of BSS.

In the Tokamak device of controllable nuclear fusion, the poloidal field power supply (PFPS) provides the dynamic magnetic field inside the device. The power level of full-controllable devices has been improved with the rapid development of high-power semiconductor technology, which promotes the upgrade of poloidal field power supply. The PFPS adopts an AC–DC–AC circuit structure, which makes the load coil operate in four quadrants. Because the load is a superconducting magnet coil, the power of the load coil will change for a period of time to meet the demand of the internal magnetic field of Tokamak, resulting in the instability of DC bus voltage. This paper proposes an optimized bidirectional buck–boost active storage unit (ASU) with unidirectional inductor current, which can quickly make the bus voltage stable. In the circuit structure, the direction of the inductor current is unidirectional, which avoids the slow response of the inductor current in the reverse direction of the traditional buck–boost converter; And the inductor has a controllable freewheeling circuit, which can reduce the disturbance of inductor current to bus charging. The number of inductors is small, which avoids the large volume of traditional dual-inductor DC–DC converter; Compared with the traditional buck–boost converter, the buck–boost ASU with unidirectional inductor current improves the energy utilization of the bus capacitor. By establishing the mathematical model of the circuit topology, the dual closed-loop controller and modulation strategy are used to control the stable operation of the system. The simulation results show that the circuit structure can balance the bus voltage well and keep stable, when the load power changes suddenly.

A typical charging profile for the li-ion batteries in electric vehicles (EVs) includes a constant current (CC) charging stage and a constant voltage (CV) charging. This letter proposes a simple and reconfigurable topology for CC and CV outputs in an EV wireless charging system. The proposed system can be switched to series-series (S-S) topology for CC output and inductor-capacitor-capacitor-series (LCC-S) topology for CV output. Only one relay is introduced, unlike existing solutions where many passive components and relays are utilized for reconfiguration. Also, there is no need for frequency variation to achieve the shift of CC and CV. An experimental prototype is implemented to validate the proposal.

A novel zero voltage switching (ZVS) interleaved high step-up converter with for renewable energy systems is proposed in this paper. By applying a switched capacitor mixed with coupled inductor and built-in transformer, the proposed converter achieves high voltage gain and minimized voltage stress across power switches. Both of the voltage gain and the voltage stress, can be adjusted by the turns ratio of the coupled inductor and built-in transformer which gives an extra degree of freedom for the converter design. Hence operating at high duty cycles is avoided and low voltage rated semiconductors can be adopted which reduce conduction losses and improve the circuit performance. Furthermore, active clamp scheme is utilized to guarantee ZVS turn ON for the power MOSFETs and the leakage inductances of the magnetic means help to provide zero current switching (ZCS) of the diodes. In such a case, switching losses are minimized and the reverse current recovery is alleviated. Accordingly, the proposed converter with reduced counterparts is a suitable candidate for high step-up and high power applications. Finally, a 600W prototype with 24V-480V voltage conversion is built to demonstrate the performance of the proposed converter.

In this paper we are presents the design and implementation of a smart energy meter using an PIC16F886 microcontroller and a liquid crystal display (LCD). It is used in residential consumer. It is an electric device having energy meter chip for measuring the electric energy consumed. It is also allowing the meter owner to have a meter utilized and the corresponding amount will be displayed on the LCD continuously. Also they can monitor the meter reading regularly without the person visiting each house. Microcontroller PIC16F886 to prevent and control the energy meter from power theft. In the voltage system whenever occurring of under voltage and over voltage condition then meter should be given a constant voltage. Keywords: Smart meter, PIC16F886 microcontroller, Power consumption, Voltage stabilizer and LCD display

Lead titanate in titanium-titanium mine and lead (solid solution optimized ferroelectric) is one of the most widely used multifunctional material systems, and they are outside the field (such as light, electricity, and heat) Structure, domain, and phase evolution characteristics are important for ferroelectric, piezoelectric, photoelectric, and memory applications. Functional materials are those high-tech materials with excellent electrical, magnetic, optical, and thermal functions, special physical, and chemical and biological effects, capable of completing functional interconversion, mainly used to manufacture various functional components and are widely used in various high-tech fields. This paper mainly analyzes iron and electrical materials and artificial intelligence technology by studying the characteristics of ferroelectric materials and research status at home and abroad and using artificial intelligence technology and the calculation of ferroelectric materials for artificial intelligence technology and Dexie optimization model. Artificial intelligence is a new technical science that studies and develops theories, methods, technologies, and application systems for simulating, extending, and expanding human intelligence. For artificial intelligence before the optimization of the hardware and software of the ferroelectric material performance test system, the optimized system is performed; the optimized system is subjected to safety testing; all test results show that the performance test of the ferroelectric material after optimization. The system data is well operating, and the artificial intelligence technology is suitable for optimization of the performance test system of ferroelectric material.

Multiple DC subgrids in close proximity can be connected to form a DC microgrid. The interconnected DC subgrids enhance reliability and efficient utilization of resources. In this paper, a novel coordinated power management strategy is proposed for interconnected subgrids of a DC microgrid. Each DC subgrid has PV and battery units. The proposed strategy is implemented on interlinking bidirectional converters (IBCs). The strategy considers the state-of-charge (SoC) and charging/discharging current of the batteries for SoC balancing-based power sharing through IBCs. A fuzzy logic controller is implemented to decide the amount of power flow through the IBCs from SoC and the charging/discharging current of battery units. Moreover, with the coordinated strategy, a high SoC battery takes more loads compared to a lower SoC battery. The proposed strategy supports fast charging and fast discharging of batteries depending on the SoC level. In addition, the coordinated strategy can seamlessly transfer the control of IBC from the power regulating mode to the voltage regulating mode without any additional control scheme during an outage of the battery unit. The feasibility of the proposed strategy is validated through simulation in MATLAB/Simulink and OPAL-RT real-time digital simulator.

The construction sector is the second largest area for the application for plastics. Due to the long life times of construction products, the implementation of the circular economy faces its own challenges. To investigate this challenge, the study covers a market study for Germany, voluntary take-back and recycling schemes of construction products, as well as the use of plastic recyclates in construction products. In addition, plastic packaging of construction products is covered. Opportunities and barriers to the use of recycled plastics in construction products are derived from the intersection of available technologies, recyclate supply, and technical requirements for construction products. The report concludes with recommendations to various stakeholders on how to promote the use of recyclates in construction products and their packaging. Important points here are the introduction of a recyclate quota for films as construction product packaging and the description of recycling possibilities and recyclate content in the technical documentation of construction products.

Micro Metal-Insulator-Metal (M-I-M) capacitor structures are well-known passive components that have been broadly used in integrated circuits, Radio Frequency (RF) decoupling, Micro Electro Mechanical Systems (MEMS) sensors, and health monitoring systems. Thanks to its small dimensions, it can be easily integrated into microelectronics. With the acceleration of the scalling dawn of integrated circuits and systems, the size of the capacitor and other components must be reduced. It has become challenging to fabricate a micro M-I-M capacitor with low leakage current and high-capacity density since the leakage current and depletion effect are reported as the main factors of the gradual loss of electrical energy in the micro-M-I-M capacitor. Thus, minimizing the leakage current and the depletion effect became a new research trend. This paper presents a penta-layer high-K dielectric between the electrodes to reduce the leakage current in the micro-M-I-M capacitor. For this purpose, various dielectric materials were investigated. It was found that niobium pentaoxide (Nb2O5) and hafnium dioxide (HfO2) as penta-layer dielectric materials provide the lowest leakage current between the two electrodes. The recorded values of leakage current density are reduced to a mere 0.95 µAmps/mm2 from several µAmps/mm2 at the operating voltage of 1 V. The reported micro-M-I-M capacitor has potential application as an energy storage device.

Electricity is one of the essential needs of human. It's commonly used for domestic, industrial, and agricultural purposes in day-to-day life. Most folks know the role of the energy meter within the electricity grid. It’s a fundamental component of the distribution grid. The energy meter helps the utility (electricity distribution company) to account for the utilization of electricity by the buyer on a KW per hour basis. To know this we want to seek out the drawbacks of the present energy meter, and therefore the biggest problem in electricity metering. The most important problem in electricity distribution is collecting meter reading data. Straight away meter reading is collected manually, which provides scope for corruption and human error in reading. It is the wastage of manpower and utility of resources. Our existing electricity meter isn't tamper-proof. There is to several temper cases are detected. In the existing meter, there is no under voltage and over voltage protection, as well as there is no over power use alert system. Because of these problems, the utility is unable to gather a fine for max demand cross. Power theft is the biggest problem in recent days, which causes a lot of loss to electricity boards. To overcome these drawbacks, the IoT-based Smart Energy Meter (SEM) is developed.

Development of small integrated antennas has played a crucial role in the current rapid progress of commercial wireless communication technology. Incorporating different radio standards, which supports various voice and data applications to a single wireless hand-held device, has now become the need of the hour. Quarter wavelength patch antennas are low profile antennas suitable for such applications. In this paper, two single-feed triple-band quarter wavelength antennas, PIFA and shorted patch antenna, having multi-band capability, are experimentally investigated and characterized. Different specifications of both the antennas are software simulated and experimentally tested. All simulations are performed using CST microwave studio.

One of the existing challenges while realizing miniaturization of the antenna is ensuring that the performance of the antenna without any negative effect has become the main focus of many researchers and pose challenges towards microstrip antenna research. In this paper, we focus on the study of miniaturization of microstrip antennas by designing miniaturized antennas, and carry out modeling and simulation. On basis of existing theory, the proposed method introduces the miniaturization technology of three mainstream microstrip antennas, namely meandering, loading, and bending slots. The electromagnetic simulation software HFSS is used to analyze the influence of the parameters of the three technologies on the antenna performance, and respectively propose a miniaturization scheme of the microstrip antenna.

The charging plate creates magnetic fluxing. The charging plate and the adjacent coil can induce current without any contact. By the new trends, wireless charging got more social attention to the outside world as an alternative method for primitive wired charging. Even though wireless charging was implemented to various electronics industries, it is still proven that wired charging is faster than the wireless. But can make the gadget hot, which may not be good for the battery efficiency. The wireless charging does not degrade the battery. A vehicle that is powered by an electric motor rather than a typical petrol or diesel engine is referred to as an electric vehicle. The electric motor is powered by rechargeable batteries. In this article, the dynamic wireless charging of electric vehicles introduces a new methodology of charging even when the vehicle is in motion. The dynamic wireless charging is proposed to allow power transfer to the electric vehicles when they are in motion. Multiple inductive pads should be buried under the roadways. The inductive pads should be energized by a power supply. The track which is dedicated for the wireless charging should have enough distance so that the vehicles can charge up to a stable value until they leave the charging track. This proposed methodology reduces unnecessary time wastage for charging of vehicles. Hardware results obtained the primary pads mounted on road and power supply for primary roads. Besides, it will flow the efficient inductive power transfer and time saving opportunity.