High-power Switching Devices Research Articles

Interface Protection and Energy Management System for Microgrid using Internet of Things

The restructuring of power systems, performance enhancements in the renewable energy generation technologies and evolutions in power electronics based high power switching devices has collectively facilitated the technical realization of microgrids in power systems. Reduction in Peak power demands on the main grid, good voltage regulation and utilization of renewable energy sources are the important technical benefits of Micro Grids with Distributed Energy Resources(DERs). Control and protection of micro grids during its various operating modes are very essential for the secure and reliable operation of microgrid interfaced main grids. Isolation of micro grids after a fault in main grid and energy management during mode transition are the important challenges of micro grids. The power electronics based micro grids requires faster isolation of faulty parts hence the operating time of the control and protection systems need to be faster. Hence this paper proposes a method for interface protection and energy management using Internet of Things (IoT).

Identification of Novel Short BaTiO3-Binding/Nucleating Peptides for Phage-Templated in Situ Synthesis of BaTiO3 Polycrystalline Nanowires at Room Temperature.

Ferroelectric materials, such as tetragonal barium titanate (BaTiO3), have been widely used in a variety of areas including bioimaging, biosensing, and high power switching devices. However, conventional methods for the synthesis of tetragonal phase BaTiO3 usually require toxic organic reagents and high temperature treatments, and are thus not environment-friendly and energy-efficient. Here, we took advantage of the phage display technique to develop a novel strategy for the synthesis of BaTiO3 nanowires. We identified a short BaTiO3-binding/nucleating peptide, CRGATPMSC (named RS), from a phage-displayed random peptide library by biopanning technique and then genetically fused the peptide to the major coat protein (pVIII) of filamentous M13 phages to form the pVIII-RS phages. We found that the resultant phages could not only bind with the presynthesized BaTiO3 crystals but also induce the nucleation of uniform tetragonal BaTiO3 nanocrystals at room temperature and without the use of toxic reagents to form one-dimensional polycrystalline BaTiO3 nanowires. This approach enables the green synthesis of BaTiO3 polycrystalline nanowires with potential applications in bioimaging and biosensing fields.

(Invited) Current Topics in Electronic Devices Based on Wide Band-Gap Semiconductors for Power Applications and Energy Efficiency

Wide-bandgap power semiconductor devices offer enormous energy efficiency gains in a wide range of potential applications. As silicon-based semiconductors are fast approaching their performance limits for high power requirements, gallium nitride (GaN), silicon carbide (SiC), and diamond, with their superior electrical properties are likely candidates to replace silicon in the near future. Along with higher blocking voltages wide-bandgap semiconductors offer breakthrough relative circuit performance enabling low losses, high switching frequencies, and high temperature operation. The progress of the development of high voltage, high current wide-bandgap power switching devices in the APRA-E SWITCHES program is reviewed. The performance of various rectifiers and transistors, which have been demonstrated, is discussed. Material and processing challenges and reliability concerns for wide-bandgap power devices are also described. A glimpse into the future trends in device development and commercialization is offered.

(Invited) Current Topics in Electronic Devices Based on Wide Band-Gap Semiconductors for Power Applications and Energy Efficiency

Wide-bandgap power semiconductor devices offer enormous energy efficiency gains in a wide range of potential applications. As silicon-based semiconductors are fast approaching their performance limits for high power requirements, gallium nitride (GaN), silicon carbide (SiC), and diamond, with their superior electrical properties are likely candidates to replace silicon in the near future. Along with higher blocking voltages wide-bandgap semiconductors offer breakthrough relative circuit performance enabling low losses, high switching frequencies, and high temperature operation. The progress of the development of high voltage, high current wide-bandgap power switching devices in the ARPA-E SWITCHES program is reviewed. The performance of various rectifiers and transistors, which have been demonstrated, is discussed. Material and processing challenges and reliability concerns for wide-bandgap power devices are also described. A glimpse into the future trends in device development and commercialization is offered.

Development of a prototype T-shaped fast switching device for electron cyclotron current drive systems

A T-shaped high-power switching device composed of circular corrugated waveguides with three ports and double dielectric disks made of sapphire was proposed as a fast switching device based on a new principle in electron cyclotron current drive systems. This switching device has the advantages of operating at a fixed frequency and being compact. The design of the prototype switch was obtained by numerical simulations using a finite-difference time-domain (FDTD) method. The size of these components was optimized for the frequency band of 170 GHz. Low-power tests were carried out in a cross-shaped model.

On the construction of power quality control systems

Some aspects of the construction of power quality control systems in power supply systems are discussed. The basic requirements for quality factors of electric power are determined, the conditions of joint parallel operation of energy consumers are considered, and analysis of traditional ways of solving the emerging problems is carried out. The advantages and disadvantages of power quality control systems related to the capabilities of new technologies with application of high-power semiconductor switching devices (GTO and IGCT thyristors, MOSFET and IGBT transistors) are considered. The application of computer technology in power quality control systems makes it possible to use rather complicated and effective algorithms of numerical processing of signals and significantly increase the accuracy of correction of disturbances in electric networks. The advantages and disadvantages of industrial plants constructed in the form of a controlled reactor with a dc magnetic bias and a reactor with a thyristor key are considered. Two types of devices to compensate for possible disadvantages are identified: devices using fully controlled keys and devices ones using artificial commutation and incompletely controlled power keys. A brief analysis of the known methods of electric power quality control is implemented. Recommendations for the establishment of power quality control systems are suggested in which the parameters of software depend on the solution algorithm of a posed problem, while the algorithm itself depends on the method of control and mathematical laws on which it is based. The method of control determines the structure of the power quality control system, while the software determines the basic operations of information processing, their quantity, the scheme of data processing, the volume data flows, etc.

Research on automatic current sharing control methods for control power supply

High-power switching devices in control power supply have different saturated forward voltage drops and the inconsistency of turning on/off times and they lead to the inconsistency in the external characteristics of the inverter modules in parallel operation. Modules with good performance in external characteristics undertake more currents and lead to overloading status and modules with bad performance in external characteristics stay in light-loading status, which increases the thermal stress of module undertaking more currents and influences the service life of high-power switching devices. Based on the simulation analysis of the small-signal module using control power supply automatic current sharing method, it is able to find out the characteristics of current-sharing loop control, namely, slow response speed of the current-sharing loop, which is beneficial for improving the stability of the entire control power supply system.

Integrated Computational Investigation of Photoconductive Semiconductor Switches in Pulsed Power Radio Frequency Applications

Successful integration of linear-mode photoconductive semiconductor switches (PCSS) into RF pulsing antenna sources may yield higher switching speeds and improved power efficiency over conventional switching methods, while also reducing size/weight. This paper presents a multiphysics computational methodology for studying linear-mode PCSS in a high-power antenna system, with a focus on extrinsically triggered widebandgap materials. A comparison with the existing literature reveals crucial performance sensitivities to photon absorption models, as well as encouraging results for the potential of PCSS as high-power switching devices.

NEW CONFIGURATIONS FOR HYBRID FILTERS TO IMPROVE POWER QUALITY

Reforms in Power Sector have given an opportunity to the consumer to demand Quality Power. Unbalance, Distortion and poor regulation in the supply voltage have detrimental effect on the life of equipment and leads to poor efficiency in operation. Variable speed drives, Electric Traction and Furnace Loads inject harmonic currents into the supply system creating Bus voltage distortion. Even linear loads connected to this Bus will experience distorted load currents. These high frequency currents do not generate any useful output but produce over heating of motors, increased reactive power demand and ripples in the generated torque causing vibrations, leading to failure and poor performance efficiency. So there is a need for bypassing the load current harmonics generated by nonlinear loads from entering the system Bus Conventionally passive tuned filters connected to the Bus are used for bypassing the harmonics, but these filters have many limitations and become less effective under some operating conditions. Advent of high frequency, high power switching devices has given rise to new tools to mitigate the harmonic distortion in the Bus Voltage by freewheeling the harmonic currents, these are generally called as Active Filters. There are many configurations of these filters. Many of the limitations faced by tuned passive filters are overcome by the use of Active filters, but by combining the tuned and active filter the reliability and affectivity in improving power quality is enhanced, these are called Hybrid Filters. This paper briefly deals with two new configurations of Hybrid filter, one based on Pulse Width Modulation (PWM) operated Voltage Source Converter and the other on Current Controlled Converter. Results of performance of these two filters applied to a simple distribution system with a nonlinear load are given.

Progress in High Voltage SiC and GaN Power Switching Devices

The present status of the development and commercialization of SiC and GaN power devices for power electronics applications is presented. The technology obstacles and needs as well as future trend in these power devices are also discussed.

A 69-mΩ 600-V-Class Hybrid JFET

A hybrid silicon-carbide junction-gate field-effect transistor (HJT: hybrid JFET) is proposed. The HJT consists of a silicon-carbide (SiC) normally-on vertical JFET and a low-voltage normally-off silicon metal-oxide-semiconductor field-effect transistor (Si-MOS: silicon MOSFET). These two devices are connected by bonding wire as a cascode circuit [1] and packaged in a TO-3P split-lead-frame package with the same pin arrangement as conventional silicon power devices, which can thus be easily replaced by the proposed HJT. The vertical JFET has a steep-junction deep-trench structure in its channel region. This structure gives a low on-state resistance of under 60 mΩ and breakdown voltage of over 600 V with the die size of 6.25 mm2. Since the deep-trench structure also lowers the cutoff voltage of the JFET, required minimum breakdown voltage of the Si-MOS is reduced and on-state resistance of the Si-MOS is lowered. The HJT demonstrated on-state resistance of 69 mΩ and breakdown voltage of 783 V. These results indicate that the proposed HJT is a strong candidate for low-resistance high-power switching devices.

기판전압에 따른 나노와이어 Junctionless MuGFET의 전류-전압 특성

In this paper, a current-voltage characteristics of n-channel junctionless and inversion mode(IM) MuGFET, and p-channel junctionless and accumulation mode(AM) MuGFET has been measured and analyzed for the application in high speed and low power switching devices. From the variation of the threshold voltage and the saturation drain current with the substrate bias voltages, their variations in IM devices are larger than junctionless devices for n-channel devices, but their variations in junctioness devices are larger than AM devices for p-channel devices. The variations of transconductance with substrate biases are more significant in p-channel devices than n-channel devices. From the characteristics of subthreshold swing, it was observed that the S value is almost independent on the substrate biases in n-channel devices and p-channel junctionless devices but it is increased with the increase of the substrate biases in p-channel AM devices. For the application in high speed and low power switching devices using the substrate biases, IM device is better than junctionless devices for n-channel devices and junctionless device is better than AM devices for p-channel devices.

Growth of Bulk GaN and AlN: Progress and Challenges

GaN-based optoelectronic and electronic devices such as light-emitting diodes (LEDs), laser, and heterojunction field-effect transistors (HFETs) typically use material grown on foreign substrates such as sapphire, Si, and SiC. However, thermal and lattice mismatch present prevent attainment of quality films deemed necessary by ever increasing demand on device performance. In fact in LEDs intended for solid state lighting, internal quantum efficiencies near 100% might be needed, and further these high efficiencies would have to be retained at very high injection current levels. On the electronic device side, high radio-frequency (RF) power, particularly high-power switching devices, push the material to its limits. Consequently, as has been the case for other successful semiconductor materials systems, native substrates must be developed for the GaN family. In this paper, various approaches such as high-pressure nitrogen solution (HPNS), ammonothermal, and Na flux methods, and an intermediary technique called the hydride vapor phase epitaxy (HVPE; to a lesser extent as there is a review devoted to this technique in this issue) along with their strengths and challenges are discussed.

Radiofrequency ablation with a high-power generator: Device efficacy in an in vivo porcine liver model

Purpose: The purpose of this study was to test the feasibility and efficacy of using a high-power generator with nondeployable electrodes to create large zones of coagulation in an in vivo porcine liver model.Methods: With approval from our institution's research animal care and use committee, 12 female swine (mean weight = 55 kg) were anesthetized and received RF ablation at laparotomy. Twenty-nine ablations were performed in four groups using: (i) a conventional 200-W generator and cluster electrode (n = 4), or an experimental prototype 250-W generator and (ii) a single, 17-gauge electrode (n = 9), (iii) a cluster electrode (n = 8) or (iv) three electrodes spaced 2.0 cm apart in a triangular configuration (n = 8). In the three-electrode group, power was applied by switching between electrodes using a prototype switching device. All electrodes were internally cooled. Ablation zone size, shape and generator data from each group were compared using a mixed-linear model with animals modeled as random effects.Results: The high-power generator was able to increase significantly the zone of coagulation. Mean (±SD) ablation diameter was largest in the switched group (4.31 ± 0.7 cm) followed by the cluster (3.98 ± 0.5 cm) and single-electrode (3.26 ± 0.5 cm) groups. Mean diameter in the high-power single-electrode group was no different than the low-power cluster group (3.25 ± 0.4 cm, p = 0.98). Circularity measures were high (>0.75) in all groups.Conclusions: Coupling a high-power generator and switching device is feasible. At higher powers, the switching device creates larger zones of ablation than cluster or single electrodes. Single-electrode ablations created with the prototype high-power generator were equivalent to those produced with the cluster electrode at conventional lower powers.

GROWTH OF SiC SUBSTRATES

In recent years SiC has metamorphisized from an R&D based materials system to emerge as a key substrate technology for a significant fraction of the world production of green, blue and ultraviolet LEDs. Emerging markets for SiC homoepitaxy include high-power switching devices and microwave devices. Applications for heteroepitaxial GaN-based structures on SiC substrates include lasers and microwave devices. In this paper we review the properties of SiC, assess the current status of substrate and epitaxial growth, and outline our expectations for SiC in the future.

SiC Bipolar Power Devices

AbstractThe successful commercialization of unipolar Schottky rectifiers in the 4H polytype of silicon carbide has resulted in a market demand for SiC high-power switching devices. This article reviews recent progress in the development of high-voltage 4H-SiC bipolar power electronics devices.We also present the outstanding material and processing challenges, reliability concerns, and future trends in device commercialization.

Application of All Solid-State Pulsed Power Generators to Equipment Using Plasmas

Recently, high-repetition-rate all-solid-state pulsed power generators with long life time and high reliability, have been developed for industrial applications with plasmas, such as high-repetition-rate pulsed gas lasers, high energy density plasma (EUV sources) and water discharges. Nowadays, power semiconductor device technology can improve the performance of fast and high-power switching devices. In practical systems, however, semiconductor switches are used with the assistance of magnetic switches because the semiconductor switches are not capable of driving the usual generators by themselves. These generators consist of semiconductor switches, step-up pulse transformers and magnetic switches. Progress of all-solid-state pulsed power generators is reviewed with particular emphasis on industrial applications with plasmas.

Importance of the “secondary breakdown energy” parameter in high–power switching transistors

The necessity in estimating the secondary breakdown energy of switching–type transistors is substantiated. The issues of improvement of reliability of high–power switching devices in bipolar transistors are considered.

High Speed and High Functional Inverter Power Supplies for Plasma Generation and Control, and their Performance

The Rapid development of high power and high speed semiconductor switching devices has led to their various applications in related plasma fields. Especially, a high speed inverter power supply can be used as an RF power source instead of conventional linear amplifiers and a power supply to control the magnetic field in a fusion plasma device. In this paper, RF thermal plasma production and plasma heating experiments are described emphasis placed on using a static induction transistor inverter at a frequency range between 200 kHz and 2.5 MHz as an RF power supply. Efficient thermal plasma production is achieved experimentally by using a flexible and easily operated high power semiconductor inverter power supply. Insulated gate bipolar transistor (IGBT) inverter power supplies driven by a high speed digital signal processor are applied as tokamak joule coil and vertical coil power supplies to control plasma current waveform and plasma equilibrium. Output characteristics, such as the arbitrary bipolar waveform generation of a pulse width modulation (PWM) inverter using digital signal processor (DSP) can be successfully applied to tokamak power supplies for flexible plasma current operation and fast position control of a small tokamak.

Generation Technologies of High Repetition Rate Pulsed Power.

Recently, high repetition rate, long lifetime, and high reliability pulsed power generators have been developed using semiconductor switches. We have studied and developed an all solid-state pulsed power generator for industrial applications such as a high repetition rate pulsed gas laser and a pulsed ozonizer. Recently, semiconductor power device technology has improved the performance of fast high-power switching devices. However, the semiconductor switch is still not sufficient to drive the pulse laser and the pulse ozonizer directly. Therefore, the semiconductor switch can be used in practical application with the assistance of a magnetic switch and a gate driving technique. This all solid-state generator consists of a semiconductor switch and a magnetic switch. The progress of high repetition rate pulsed power generators is reviewed herein, with particular emphasis on pulse power conditioning by solid-state switching techniques.