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This paper reviews on hybrid systems (PV and Wind) for electric vehicle charging stations (EVCS). In the period of electrified transportation, insufficient infrastructure of charging and shortfall of energy storage technology are the serious issues to be conveyed which drive the market to switch hastily to electric vehicles (EV). Existing charging stations use electric grid for EV charging, but EV integration with electric grid results in the increase of stress on the grid. Due to this drawback, renewable energies like solar photovoltaic systems and wind systems are used. In this paper, EVCS overview and impacts on the grid have been investigated. This paper reviews the topologies of bidirectional converter that can be used in hybrid system for EVCS. [ABSTRACT FROM AUTHOR]

As one of the countries in Southeast Asia, Indonesia is making an energy transition in the transportation sector by using battery-based electric vehicles (BEV). The Indonesian government supports accelerating electric car use by issuing Presidential Regulation of the Republic of Indonesia Number 55 of 2019 concerning the Battery-Based Electric Motorized Vehicle Acceleration Program. The level of consumers buying electric cars is still low due to a lack of awareness about several aspects, including the economy, benefits, accessibility, and environmental concern. On the other hand, the relatively expensive purchase price of electric cars is a consideration or even an obstacle for people to switch to using electric cars. This study aims to understand which factors hinder the adoption of electric cars in DKI Jakarta. Using questionnaire method with probability sampling and cluster sampling research techniques based on cities in DKI Jakarta Province. Electric vehicle prices, infrastructure, and policies are the most important factors hindering electric car adoption in DKI Jakarta. [ABSTRACT FROM AUTHOR]

The switching conditions are largely characterized by the specifics of the intermittent nature of the brush contact with each collector plate. The current distribution in the brush contact is determined by the lapping of the working brush to the collector and the state of the varnish film, which determines the nature of the "mirror" on the working surface of the brushes. A varnish film on the working surface of the collector or the current-collecting ring is a prerequisite for ensuring satisfactory switching of electric machines. An important aspect in this regard is the structure of the varnish film. The structure of the varnish film is determined both by the composition of the atmosphere in which it is formed (gas composition, humidity, salinity), and by the electrical processes occurring in intermittent contact in the sliding current collector unit. In some cases, the varnish film may not form and thus significantly degrades the sliding friction and current transfer conditions. Under these conditions, the wear of the brush – collector pairs (current-collecting ring) – increases significantly. Therefore, it is important (in the conditions of a weak protective varnish film or its absence) to use the techniques of its artificial guidance. The article considers a variant of directing a varnish film using an active oxidation catalyst. This solution may be of considerable interest for electric machines operating in the conditions of a discharged atmosphere and the atmosphere of workshops with low oxygen content. [ABSTRACT FROM AUTHOR]

The article deals with the issues of improving the safety of transportation by optimizing the information provided about the current state of station equipment, by increasing the efficiency and reliability, monitoring the state of devices of control systems in railway transport. These goals are achieved by implementing digital methods of information processing, performing current control, one of the significant devices, and station switches. It is noted that this device has four States and to optimize the algorithm of output information proposed and investigated model using network graphs Petri dishes. Based on the simulation results, algorithms are developed, methods and methods are defined for reflecting all four States of the switch on the monitor of the automated workplace of the station attendant. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) and hybrid electric vehicles (HEVs) have been widely regarded as the most promising solutions to replace the conventional internal combustion (IC) engine-based vehicles, and the recent years have seen a rapid development of EV and HEV technologies. Energy storage technologies are increasingly emerging with the popularity of electric vehicles. Owing to its high efficiency and low emissions, the battery is one of the most common energy storage systems. Battery management system (BMS) is vital in ensuring safe and reliable operation of batteries. Switching to electric vehicle revolution is taking too much time especially in India due to its high charging time of batteries and inadequate charging infrastructure. Battery swapping is one of the methodology developed to solve this problem. Battery swapping is a method in which a vehicle's discharged battery pack can be immediately swapped with a fully charged one, eliminating the delay involved in waiting for the vehicle's battery to charge. But for large vehicles battery swapping become complex since the battery size is very large. Costly battery swapping station with robotic mechanism is needed to swap the battery. To solve this problem in this paper we have suggested a new battery swapping method called modular battery swapping where the battery is arranged as a number of modules and can be swapped one by one easily with our hands. We have modelled an electric vehicle having this modular battery swapping feature using MATLAB, which drives based on a locally developed drive cycle. Different functions of BMS are also included in the MATLAB EV model. [ABSTRACT FROM AUTHOR]

We investigate scattering of a silicon nanoparticle optically isolated from a silicon substrate by a silica layer. We observe characteristic Fabri-Perot behavior of scattering cross section with the increasing of the sublayer thickness. We show that we can independently suppress or enhance the scattering at frequencies of electric and magnetic dipole resonance. Setting a certain angle of incidence and the sublayer thickness, a polarization induced switching between electric and magnetic dipole is achieved. Finally, directivity of scattered radiation is investigated. Regimes with negative angle scattering, conical and upward radiation patterns are observed. [ABSTRACT FROM AUTHOR]

The paper presents selected elements of logic synthesis of low power FSM. Authors focus on the problem of low power coding for internal states. Proposed coding algorithm leads to reduction of the number of switches and as a result reduction of dynamic power consumption. The paper shows, that effective coding algorithm is insufficient for effective FSM synthesis. A vital role in logic synthesis plays technology mapping. This process requires appropriate function decomposition. The paper presents methods of carrying out technology mapping which uses triangle tables. This method leads to appropriate decomposition path. The experimental results show that effective states coding must be associated with effective technology mapping. [ABSTRACT FROM AUTHOR]

This paper presents the design of 5 V to 20 V DC switching regulator for power supply module. A voltage multiplier which consists of cascaded diode-capacitor combination is used in order to obtain a high voltage power supply. Due to power loss that has occurred in a stray of component arrangement, the proposed design employs a pulse width modulation (PWM) controller circuit with an inclusion of a capacitor, diode, and inductor components. The input supply of 5 V DC to LT1618 controller circuit has produced 20.35 V based from simulation results. Meanwhile, the measurement results of 19.36 V are obtained and the feedback signal is required for the purpose of stabilizing the output. The proposed design can reduce the components as well as the PCB size, thus minimizing the overall cost of making a switching regulator for power supply module. [ABSTRACT FROM AUTHOR]

This paper presents an approach for determining temperature distribution on a 2200A busway model. Solidwork software was used in order to create 3D modeling of busway model. This paper proposes a simulation model developed by coupling the multiphysics between electrical analysis and thermal analysis. The coupling was done by using ANSYS Workbench and ANSYS Maxwell. Basically, the electrical analysis is performed onwards busway model in order to get the value of ohmic loss which is heat loss from the conductors in the busway. The ohmic loss results will be imported to thermal analysis in order to get the temperature result as well as temperature distribution. First, the direct current loading of the busbar, which neglect the alternating current effects, was considered. Second, the alternating current loading of busbar was used instead of direct current loading. The model of the second approach gives much more accurate result in term of temperature difference. The presented model was validated against temperature measurement on real size busway under electrical loading. The obtained results show that a very good agreement between computed and experimental data. Once the verification of the model is done, the busway configurations setup behavior is studied. Increasing number of feeder affects thermal stress concentration on busway joint. [ABSTRACT FROM AUTHOR]

The IEC 61400-21 standard defines the measurement procedure for the flicker generated by wind turbines (WTs). The standard specifies minimum bandwidths of 400 Hz or 1 500 Hz for the flicker characterization during continuous or switching operations of the WT, respectively. During a switching operation, the waveforms of the voltages and currents change abruptly, generating spectral components over a larger bandwidth than during continuous operation. The aim of this work is to assess the suitability of the 1 500 Hz bandwidth requirement for flicker characterization during switching operations. The study involves real voltage and current signals recorded at a WT located in a Spanish wind power plant. It confirms the existence of frequency components well above 1 500 Hz in the current and voltage signals that accompanied switching operations. The results also reveal significant differences between the flicker step factors calculated using the original input bandwidth (10 kHz) and those calculated using other input bandwidths (from 1 to 9 kHz). These differences increase progressively as the input bandwidth is reduced. The differences are also dependent on the length of the analyzed interval that contains the switching operation. The study shows that flicker measurements of WTs during switching operations may be inaccurate if an input bandwidth below 1 500 Hz is used. [ABSTRACT FROM AUTHOR]

Some issues regarding the analysis of poly-phase voltage rectifier operation will be presented in this paper. The switch is an uncontrolled-type, a diode in this case, which is considered as an ideal one. The expressions of the parameters characterizing the rectifier operation are computed in the paper. Their variations depending on load are also discussed [ABSTRACT FROM AUTHOR]

The electromagnetic (EM) method has been widely used in geophysical surveys. It is a non-destructive method that utilizes electromagnetic waves in characterizing subsurface profiles. Generally, EM method can be divided into passive EM and active EM. The passive EM uses the natural electromagnetic field sources, while the active EM or Controlled Source EM (CSEM) uses artificial source to generate electromagnetic wave. In this paper, we present the development of AC power source for CSEM transmitter. As the power source we used AC source with sine wave signal. To satisfy a high power and high voltage in the equipment, we used the full-bridge configuration switching. It works on 990 Hz maximum frequency, and can deliver maximum current of 1.9 A at 620 V. The switching is controlled by microcontroller using Pulse Width Modulation (PWM) and the driver of inverter is built using IGBT. The output frequency can be varied from 1 Hz to 990 Hz. For varied frequencies the harmonic distortion is different due to switching speed. As frequency increase the harmonic distortion also increase. We found that the total harmonic distortion can be reduced to 1 % at the output with 330 Hz. [ABSTRACT FROM AUTHOR]

In an integrated DC-DC converter, voltage spikes are generated during the commutation of the power switches and they may cause the device malfunction if its magnitude is excessive. That occurs when, targeting high efficiency, very fast switching is implemented in a low voltage CMOS process, with higher impact when the converter output current is high. These conditions that cause spikes of significant magnitude, in the order of Volts, are common in modern DC-DC converters for portable equipment powered by batteries. Magnitude limitation of voltage spikes in hard switching converters is a hot research topic and the known solutions are surveyed here. Resonant switches topologies are frequently mentioned as an alternative to overcome voltage spikes in a DC-DC converter, but generally this solution is dismissed in integrated implementations. This paper investigates if the resonant topologies are an effective solution to overcome voltage spikes during the switches commutation in a buck converter. Two buck DC-DC converters using resonant switches are analyzed, namely a QR-ZCS topology and a QSW-ZVS topology. The analysis proceeds in two steps that can be easily applied to other resonant converters. Results show that resonant DC-DC converters also generate voltage spikes which magnitude is sometimes higher than that generated in a hard switching converter, and is superimposed to the overvoltage occurring in the resonant phase. This is an important result since resonant, or soft switching, converters are occasionally mistakenly mentioned as free of voltage spikes. [ABSTRACT FROM AUTHOR]

Some issues regarding the analysis of single-phase voltage rectifier operation will be presented in this paper. The switch is an uncontrolled-type, a diode in this case, which is considered as an ideal one. The expressions of the parameters characterizing the rectifier operation are computed in the paper. Their variations depending on load are also discussed. [ABSTRACT FROM AUTHOR]

Multilevel inverter is energy conversion device that is generally used in medium-voltage and high-power applications. It offers lower total harmonic distortion, switching losses and voltage stress on switches than conventional inverter. In this paper, a novel multilevel inverter topology with the decreased number of power switches is proposed, and its modulation technique is introduced. This multilevel inverter structure consists of the level module units to enhance the level of the output voltage. Since a level module unit consists of only a DC voltage source and a bidirectional switch, this structure allows a reduction of the system cost and size. Effectiveness of the proposed topology has been demonstrated by analysis and simulation. [ABSTRACT FROM AUTHOR]

Guidelines for moisture level measurement, moisture data interpretation, and moisture control in gas-insulated switchgear (GIS) are provided. [ABSTRACT FROM PUBLISHER]

The energy distribution industry is giving greater attention to smart grid solutions as a means for increasing the capabilities, efficiency and reliability of the electrical power network. The smart grid makes use of intelligent monitoring and control devices throughout the distribution network to report on electrical properties such as voltage, current and power, as well as raising network alarms and events. A further aspect of the smart grid embodies the dynamic rating of electrical assets of the network. This fundamentally involves a rating of the load current capacity of electrical assets including feeders, transformers and switches. The mainstream approach to rate assets is to apply the vendor plate rating, which often under utilizes assets, or in some cases over utilizes when environmental conditions reduce the effective rated capacity, potentially reducing lifetime. Using active intelligence we have developed a rating system that rates assets in real time based upon several events. This allows for a far more efficient and reliable electrical grid that is able to extend further the life and reliability of the electrical network. In this paper we describe our architecture, the observations made during development and live deployment of the solution into operation. We also illustrate how this solution blends with the smart grid by proposing a dynamic rating system for the smart grid. [ABSTRACT FROM AUTHOR]

Sub-THz oscillations in a n+-n0-n+ structure analogous to those observed in GaAs bipolar junction transistor (BJT) during its superfast switching are demonstrated numerically. Negative differential mobility at extreme fields is a necessary condition for those oscillations as well as in BJT. An anode domain serving as the source of impact-generated holes manifests itself in one of two possible regimes. Fist one is the oscillation-free steady-state mode, while in the second one periodical picosecond current oscillations appear due to generation and annihilation of unstable anode domain. Some conditions affecting transitions between oscillating and oscillation-free modes have been investigated. [ABSTRACT FROM AUTHOR]

Capacitive and ohmic RF MEMS switches are based on micron-sized structures moving under electrostatic force in a gaseous environment. Recent experimental measurements [4, 5] point to a critical role of gas-phase effects on the lifetime of RF MEMS switches. In this paper, we analyze rarefied flow effects on the gas-damping behavior of typical capacitive switches. Several damping models based on Reynolds equation [7, 8] and on Boltzmann kinetic equation [9, 6] are applied to quantify the effects of uncertainties in fabrication and operating conditions on the impact velocity of switch contact surfaces for various switch configurations. Implications of rarefied flow effects in the gas damping for design and analysis of RF MEMS devices are discussed. It has been demonstrated that although all damping models considered predict a similar damping quality factor and agree well for predictions of closing time, the models differ by a factor of two and more in predicting the impact velocity and acceleration at contact. Implications of parameter uncertainties on the key reliability-related parameters such as the pull-in voltage, closing time and impact velocity are also discussed. [ABSTRACT FROM AUTHOR]

In geophysical testing, resistivity method is already widely employed. However, in developing countries the available resistivity equipment is mostly 1D resistivity system which employs four electrode configurations to measure the resistivity of soils. The multi channel resistivity system is simply too expensive for ordinary private geophysical company. Only governmental offices whose main job is to do geophysical research can afford to purchase multi channel resistivity system. In order to suppress the cost of the Multi Channel Resistivity System, this research develops multi channel resistivity system with programmable multiplexer switch and makes use of the already available 1D resistivity equipment as current injector. The new system consists of National Instruments PXI with programmable multiplexer switch cards, an Analog to Digital card to read the data, multi wires take-out cables and thirty two electrodes. [ABSTRACT FROM AUTHOR]

The present paper reports the measurements of the arc interrupting capability and calculation of the electromagnetic force of an arc quenching chamber equipped with deion plates,. The interrupting capability of an ac current was measured to be about 350 A for four plates made of copper (condition named C1-4). Locating four deion plates made of iron at the same intervals (condition I1-4) led to the interrupting capability to increase to about 600 A. In contrast, positioning the same number of the plates at a wider interval (condition I1,3,5,7) resulted in further increase in the capability to 900 A. Calculation of the magnetic-flux density distribution in the cross-section of a cylindrical conductor revealed that placing the four plates produced more asymmetrical distribution for the condition I1,3,5,7 than for I1-4. Further calculation of the electromagnetic force applied to the conductor showed that arranging the deion plates gave a higher force under the condition I1,3,5,7 than under I1-4. [ABSTRACT FROM AUTHOR]

The article examines serial resonant inverter for heating fluids with parallel inclusion of inductor to the switching capacitor. The nature of the load requires the selection of an inverter with the best energetic performance. The purpose of this article is to analyze the methods for regulating the output power, respectively, the temperature of heated fluid. After a series of studies the authors have detail examined of different methods: change the switching capacitor - Ck, changing the ratio of the resonant frequency to switching frequency (a=ω/ωO), and changing the pulse width modulation (D=tu/T). Dependencies are obtained, which can be a suitable choice of the method under different regulatory requirements of the load. [ABSTRACT FROM AUTHOR]

A study of LCC resonant DC-DC converter with capacitive output filter is accomplished. To this end, a harmonic analysis is used. Expressions for determination of main quantities of the converter are obtained. The areas of commutation of the power switches are determined at both zero current and zero voltage. [ABSTRACT FROM AUTHOR]

In order to achieve the purpose of energy economization by reducing the operating voltage of an asynchronous motor when it's running at no load or light load, a new kind of intelligent energy-saving motor controller is designed in this paper. This controller judges different load conditions by collecting the operating current, and it has the function of tracking the load automatically in accordance with the current changes. The controller also can precisely achieve phase voltage regulation and obviously reduce the fluctuation of the operating current through carrying out the adaptive fuzzy-tuning PID control to power factor angle so as to adjust the trigger angle of the thyristors to following the changes of power factor angle timely and accurately. At last, we have done experiments and the results demonstrate that the controller successfully achieves the purpose of energy saving, and runs reliably and steadily. [ABSTRACT FROM AUTHOR]

Small slope switches with very small subthreshold swings have been proposed recently to overcome the IC power problem. In the case of these new devices the source/drain current controlled by the gate is either due to avalanche breakdown (IMOS) or band-to-band tunneling (TFET). The impact of these new transport mechanisms on noise is investigated. The performance of the IMOS is not very promising. Its noise is by orders of magnitude too large due to the avalanche breakdown and it consumes too much power. In the case of the TFET the noise is similar to conventional MOSFETs, but the gate/drain correlation coefficient of noise is larger. [ABSTRACT FROM AUTHOR]

Researchers at The University of Michigan have constructed and tested a 1-MA Linear Transformer Driver (LTD), the first of its type to reach the USA. The Michigan Accelerator for Inductive Z-pinch Experiments, (MAIZE), is based on the LTD developed at the Institute of High Current Electronics in collaboration with Sandia National Labs and UM. This LTD utilizes 80 capacitors and 40 spark gap switches, arranged in 40 “bricks,” to deliver a 1 MA, 100 kV pulse with 100 ns risetime into a matched resistive load. Preliminary resistive-load test results are presented for the LTD facility. Planned experimental research programs at UM include: a) Studies of Magneto-Raleigh-Taylor instability of planar foils, and b) Vacuum convolute studies including cathode and anode plasma. [ABSTRACT FROM AUTHOR]

We present the recent results of our research on the high power ultra-fast silicon RF switches. This switch is composed of a group of PIN diodes on a high purity silicon wafer. The wafer is inserted into a cylindrical waveguide under TE01 mode, performing switching by injecting carriers into the bulk silicon. Our current design uses a CMOS compatible process and the device was fabricated at SNF (Stanford Nanofabrication Facility). 300 ns switching time has been observed, while the switching speed can be improved further with 3-D device structure and faster driving circuit. Power handling capacity of the switch is at the level of 10 MW. The switch was designed for active X-band RF pulse compression systems — especially for NLC, but it is also possible to be modified for other applications and other frequencies. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Summarized results obtained in several experiments on active RF pulse compression at X-band using the Omega-P/NRL magnicon are presented. In these experiments RF energy is stored in two parallel-fed resonators and then discharged using switches activated with rapidly-fired plasma discharge tubes. New results with both transmission and reflection switches are reported, with peak power gains in the range of 8–10. The application of developed plasma switches for an electrically controlled switching of an existing passive pulse compressor SLEDII for increasing its efficiency is discussed. The low-power test of the plasma switch with a 35 m SLEDII delay line is described. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

What’s there, and how much? Given some data, which of an object’s possible components are present, and at what quantity? By their nature, digital ON/OFF problems can lack continuity, and the likelihood function may well have awkward properties that inhibit many of today’s algorithms. A solution to some of these problems is to use nested sampling, which explores the state-space more directly, and can be rather easier to implement as well as having more power. Exploring the plausible patterns of switching involves digital choices, which can be interpreted in terms of a competition between transition engines that supply plausible exploratory steps. When quantitation is included, it is usually helpful to marginalise over the quantities being changed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Single-wall carbon nanotube suspension in D2O was used as a passive Q-switch for self mode-locking in flash-lamp pumped solid state lasers with different active media providing the output radiation with different wavelengths: YAG:Nd (λ=1064 nm), YAP:Nd (λ=1340 nm) and Nd-doped glass (λ=1055 nm). © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Gamma-irradiation effects on the electrical parameters of the Diode AC switch (DIAC; PHI37 500) and Silicon Controlled Rectifier (SCR; 2N4444) devices have been studied in detail, where gamma-dose up to 137 × 106 rad was found to cause a serious permanent damage on their electrical characteristics. A pronounced increase in the break-over voltage (from 31.5 to 35 V), holding-current (from 13 to 53 mA) and holding voltage (from 22 to 32 V) of the DIAC is noticed. Besides, a severe decrease in the dynamic break-over voltage range (from 10 to 2.5 V) and negative resistance (from -750 to -168 ohm) is also observed. Exposing the SCRs to gamma-radiation causes their turn-on voltage and forward voltage drop values to increase from 0.8 to 2.8 V and from 1.4 to 4.5 V, respectively. Additionally, the holding current increases to 18 mA although its initial value is 3.5 mA. For the two devices, the linear dependence and high sensitivity of their electrical parameters to gamma-dose suggest the application of such devices in the field of radiation dosimetry. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]