High-voltage Elements Research Articles

On Optimization of Manufacturing of Bipolar Heterotransistors Framework Circuit of a High-voltage Element or to Increase Their Integration Rate: On Influence Mismatch-induced Stress

In this paper, we introduce an approach to decrease dimensions of bipolar heterotransistors framework a circuit of a voltage divider biasing common emitter amplifier. Framework of the approach, we consider manufacturing of the divider in heterostructure with specific configuration. Several specific areas of the heterostructure should be doped by diffusion or by ion implantation. After this doping, dopant and/or radiation defects should be annealed by using optimized scheme. We also consider an approach to decrease value of mismatch-induced stress in the considered heterostructure. To make prognosis of technological process and obtain recommendations to optimize the process, we introduce an analytical approach to analyze mass and heat transport in heterostructures with account mismatch-induced stress.

On Optimized Manufacture of Bipolar Hetero transistors in a High-Voltage Element or for Increasing of their Integration Rate. Accounting Mismatch-Induced Stress

On Optimized Manufacture of Bipolar Hetero transistors in a High-Voltage Element or for Increasing of their Integration Rate. Accounting Mismatch-Induced Stress

Busbars for the Switchgears and Internal Connections of the Power Plants and 6- to 750-kV Substations

The use of rigid noncorona busbars with the air insulation, gas-filled current leads, and current leads with the polymeric insulation to connect various high-voltage elements at plants and substations allows providing a decrease in the electric energy losses, increase in reliability and safety of operation, as well as improving the ecological situation at the plants and substations. Compactness of the busbars is provided due to the use of new insulation media (first and foremost, electrically high-strength gases and polymeric dielectrics), as well as improvement of the technology of production and use of these materials. At present, various types of high-voltage current leads are used: shielded air busbars, busbars with the cast polymeric insulation, and sealed shielded current leads with the basic high-strength gas insulation. Engineering solutions in which insulation media with low dielectric permeability are used and the buses are made noncorona with rated operating voltage are applied to reduce the losses in the busbars.

On Approach to Increase Density of Field-Effect Heterotransistors Framework Circuit of a High-Voltage Element OR by Optimization of Technological Process

On Approach to Increase Density of Field-Effect Heterotransistors Framework Circuit of a High-Voltage Element OR by Optimization of Technological Process

On Optimization of Manufacturing of a High-Voltage Element AND with Two Inputs Based on Heterostructures to Increase Density of Their Elements. Influence of Miss-Match Induced Stress and Porosity of Materials on Technological Process

On Optimization of Manufacturing of a High-Voltage Element AND with Two Inputs Based on Heterostructures to Increase Density of Their Elements. Influence of Miss-Match Induced Stress and Porosity of Materials on Technological Process

On Approach to Optimize Manufacturing of Field-Effect Heterotransistors Framework Circuit of a High-Voltage Element OR to Increase Their Integration Rate. On Influence Mismatch-Induced Stress

On Approach to Optimize Manufacturing of Field-Effect Heterotransistors Framework Circuit of a High-Voltage Element OR to Increase Their Integration Rate. On Influence Mismatch-Induced Stress

Calculation of Low-Frequency Magnetic Field Distribution of a Transformer Station in Stationary State

This paper describes one way of assessment of exposure level to electromagnetic fields of secondary electronic equipment or personnel in or close to high-voltage facilities. Assessment of fulfilling criteria regarding allowable values of magnetic flux, according regulations, was gained by numerical calculation and experimental measurement, considering geometrical configuration of high-voltage facility elements. Correct identification of electromagnetic disturbances of transmission lines has for a result optimal geometrical disposition of electronic equipment inside a high-voltage facility. Comparing a calculation results and results of experimental measuring on particular example of high-voltage facility, can lead to a conclusion that expensive measuring can be avoided, through standardization of a mathematical model and through numerical calculation of low-frequency magnetic field distribution even in conditions of the most complex geometry. Having in mind a number of locations where interaction between high-voltage facility and electronic equipment and personnel exists, a clear intention of authors, for reducing expenses of recording interaction level, is visible.

Risk and Consequences of Transformer Explosions and Fires in Nuclear Power Plants / Ryzyko I Konsekwencje Wybuchów Transformatora I Pożarów W Elektrowniach Jądrowych

Abstract The high failure frequency and the resultant reliability and safety implications in recent years of transformers, in particular at nuclear power plants (NPP), required an in-depth assessment. Fires of main transformers are considered as critical because of the large quantity of oil in contact with high voltage elements. Therefore, these phenomena have been investigated in more detail using the information from the OECD FIRE database for NPP. 12.8 % of all fires and, thus, the most frequent fire source in this database are transformer fires, mainly fires of high voltage oil-filled transformers. Thus, possible diagnostic measures to avoid such events and enhance the reliability currently discussed in Germany are shortly described. Moreover, consequences of transformer failures with respect to a reliable electric power supply are addressed.

Control system of a linear induction accelerator of an X-ray complex: Structure, hardware, and test performance

The structure, operation logic, and hardware tools of the control system of a linear induction accelerator for an X-ray complex are considered. The hardware developed in the CompactPCI standard for the control system is described. The possibility of embedding of smart microelectronic equipment into high-voltage elements of the facility is analyzed.

High-voltage solar elements based on polycrystalline silicon

Problems connected with developing designs of high-voltage solar elements (SE) with vertical p- n transitions on the basis of polycrystalline silicon and also the results of analysis of new experimental data are considered. The photoelectric characteristics of SE with unilateral and bilateral illumination are presented. The prospects of using these SE in solar modules with parabolic-spherical and parabolic-cylindrical radiation concentrators are discussed.

High-voltage elements of a tandem accelerator with vacuum insulation

The design of a tandem accelerator with vacuum insulation intended for obtaining a proton beam with an energy of 2.0 MeV and a direct current of several tens of milliamperes is described. Calculated and experimental data obtained in tests of both a glass-ceramic feedthrough insulator for a voltage of 1.0 MV and high-voltage vacuum accelerating gaps with electrodes of area of tens of square meters are presented. Issues of optimizing high-voltage aging of the tandem in the cases of its complete and partial breakdowns are considered. The first experimental results of tests of the breakdown strength of individual high-voltage elements and the tandem as a whole are presented.

High-Voltage Gaps in a Tandem Electrostatic Accelerator with Vacuum Insulation

Theoretical and experimental results on the development and testing of a system of high-voltage vacuum accelerating gaps with electrode areas of several tens of square meters are presented. The energies stored in individual gaps may reach several tens of joules. The work is carried out as part of a program aimed at the development of a tandem electrostatic accelerator with vacuum insulation designed for a proton energy of 2.5 MeV and current of several tens of milliamperes. Optimization of the high-voltage part of the tandem with respect to the overvoltage arising in high-voltage elements of the tandem during its full or partial breakdown and to the energy stored in capacitors formed by the vacuum accelerating gaps and related elements of the tandem is considered. Experimental data on the electric strength of a 45-mm vacuum gap for different energies released in the breakdown are presented. For an electric field intensity of several tens of kilovolts per centimeter, the value of the field-emission current in a high-voltage gap with electrodes of a large area is estimated.

20.3: Super‐High Luminance Light‐Source Device with Carbon Nanotube Emitter

AbstractCarbon nanotubes (CNTs) have been attracting considerable attention as field emitters. An excellent performance of carbon‐nanotubes as field‐emitters was demonstrated using a high‐voltage FED element at Society for Information Display (SID) in 1998 where a lighting element for outdoor large size display and a flat panel were presented with the screen printed nanotube cathode. After that, we reported experimental results of a light source tube which was able to be emitted luminous flux of more than 1000lm in prospect at International Display Workshops'00 (IDW'00).In this paper, we described a light‐source device which performed super‐high luminance with special multi‐walled nanotubes (MWNTs) called nanografiber (NGF) as field emitters. The electrodes passed through electrons was improved for more uniform landing to the phosphor screen. X‐ray shield and cooling for phosphor screen were investigated for a practical use and life‐time confirmation. The device was experimentally applied to one of projection displays with liquid crystal display (LCD) as light sources.NGF cathodes have been tested under dc driving condition with high current and high anode voltage(25–30kV) against high voltage ion bombardment. The degradation of phosphors has been tested to maintain super‐high luminance under high density electron irradiation and efficient cooling.

11.3: Invited Paper: Lighting Elements of Carbon Nanotube Field Emission Display

AbstractEach year the Society awards the Display of the Year Award to several display devices that exhibit leading edge technology or innovative solutions to an information display need. The following paper provides a summary of a Display of the Year award recipient from 1999 and 2000 SID conferences. The display described Carbon‐nanotube(CNT) Field Emission Display(FED) has produced the first commercial product as a lighting element, which is a 1‐pixel 20mm‐diameter cylindrical device intended to replace existing externally similar thermionic (CRT‐type) lighting elements used in outdoor displays and other high‐brightness applications.An excellent performance of carbon‐nanotubes as field‐emitters was demonstrated using a high‐voltage FED elements at SID in 1998 where a light‐source tube for outdoor large size display and diode type flat panel were presented with the screen printed nanotube cathode.After that, an x‐y addressable high‐luminance FED panel was introduced at IDRC in 1999. The experimental panel was performed ca.7×105 cd/m2 green light at 6kV, ca.1mA/cm2 dc‐driving condition.The results show the excellent performance of carbon nanotube FED as flat panel displays which are applicable to large size TV devices. This panel will be not only suitable for future TV display but also light‐sources for field sequential color LCDs.The CNT FED lighting‐element module is exciting not only because it is the first commercial implementation of CNT technology, but because it could pave the way for new generations of FED products.

Design of a high-power NMR probe for low-temperature studies.

A low-temperature, high-power NMR probe head design is described which eliminates the problem of electric arc discharge commonly experienced during radiofrequency pulse cycling in a helium environment. A polychlorotrifluoroethylene (Kel-F) coil former, fitted with a solenoid coil, is heat-shrunk onto stainless-steel flanges and spot-welded inside a stainless-steel probe head assembly connected to a hollow coaxial transmission-line probe shaft. By this means, the sample coil and all high-voltage elements can effectively be isolated in a vacuum, while at the same time permitting good thermal contact between the sample and cryogenic gas. This design was used in NMR studies in the 4.6 K < or = T < or = 77 K temperature range for RF pulse durations < or = 50 ms (and longer for low RF amplitudes) and amplitudes up to approximately 60 G.

Ionization in the magnetized ionosphere surrounding a high voltage sphere

The interaction of a high-voltage element with the ionospheric plasma at LEO altitudes is an area of current interest because of the anticipated use of high-voltage power sources on future space platforms. Depending on the current collection characteristics, an exposed high-voltage element can lead to power losses or arcing. In an effort to elucidate high-voltage current collection characteristics, there is an ongoing series of rocket and laboratory experiments involving the interaction of high-voltage spheres with an ambient plasma. In support of this effort, we solved the time-dependent, three-dimensional, nonlinear fluid equations for ions and electrons and the Poisson equation in order to study the initial response of a partially-ionized, magnetized plasma to positive high-voltage spheres. Our emphasis was on the effect that collisions and impact ionization have on the sphere-plasma interaction. Different neutral densities (10 11–10 14 cm −3), species (Ar, Ba, O, N 2), and magnetic field strengths were considered. Our simulations indicate that a rapidly rotating electron density torus tends to form around a high-voltage sphere embedded in magnetized partially-ionized plasma. Since the electrons orbit the sphere before striking it, the high toroidal density and long travel time lead to enhanced collisional and ionization rates (relative to the no B -field case), which act to modify the torus, sheath, and current collection characteristics. The high toroidal density and long travel time also reduce the neutral density (pressure) requirement for a discharge, by an order of magnitude. Depending on the applied voltage, neutral gas pressure, and magnetic field, we obtained steady toroidal configurations both with and without ionization, a toroidal discharge, and a spherical discharge. These results are in qualitative agreement with measurements.

Accuracy of calculations of electrostatic fields by means of measuring high voltage

When developing means of measuring high voltages it is necessary to know the accurate values of the parameters of the electrostatic fields produced in these devices by electrodes of complex shape. This enables one to eliminate corona and leakage currents over the surface of the insulation in the construction, and it is necessary in order to determine the metrological characteristics of the means of measurement. When designing electrostatic voltmeters and comparators for the absolute measurement of high voltage [i] the problem of determining the partial capacitances of the sensitive elements of the means of measurement is therefore an extremely important one. A calculation of the field-strength distribution over the height of a resistive pulse-voltage divider enables one to determine such an important divider characteristic as the response time [2] etc. Since it is extremely difficult to measure the field strenth experimentally, and in the immediate vicinity of the surface of high-voltage elements is often impossible in the present state of measurement technique, theoretical methods are of considerable importance. For this purpose the method of expansion in series in nonorthogonal functions [3] is widely used; this is called the method of equivalent charges in the electrical literature [4]. In particular, this method has been used to investigate the properties of resistive voltage dividers [2], capacitive dividers [5] etc. The method of expansion in series in orthogonal functions consists in representing the solution of Laplace's equation

Measurements of the Electrical Niose Produced in the Carrier Band by a DC Converter

As part of a program to develop better tools for predicting noise levels from DC converters, a series of measurements were made of the noise levels produced by the Arrowhead converter of the Square Butte project. In this paper both measurement techniques and measurement results are presented. Voltages were measured on both the ac and the dc systems and on both the line and valve sides of the smoothing reactor and converter transformers. Valve side measurements were made possible by a divider that uses a bushing as the high voltage element. Operation of a noise meter is discussed and a circuit shown that allows quasi-peak levels to be measured with an instrument that normally does not provide a quasi-peak function. Quasi-peak levels are shown to be 7-12 dB higher than average levels. Effects of meter bandwidth are discussed. Internal resonances in the smoothing reactor are shown to be the cause of pronounced peaks and valleys noted on line side measurements. The data suggests that a simple 1/f curve of appropriate magnitude may be a sufficient model of the frequency dependent noise produced by the valves.

150 V High Voltage Linear IC Technology

A new structure, called a Semi-Well Isolation (SWI) IC structure, suitable for high voltage IC and its process technologies are developed for 150 V consumer ICs. The SWI structure has an epitaxial layer of two different thicknesses, and different impurity profiles if desirable. High voltage elements are formed in the thick portion, the isolation region and small signal elements are formed in the thin portion. As results, both high voltage transistors and low voltage ones are optimized separately on the same chip. A color TV vertical deflection output IC, which operates from a transformerless voltage source, is developed using the SWI structure.

Mechanical features of the electrostatic deflector for the Berkeley 88-inch cyclotron

The mechanical features of the electrostatic deflector are described. The deflector channel starts as close as possible to the dee. It must deflect the particles enough to clear the leg of the magnet. The channel width at entrance is 5/32 in. (0.4 cm) and at exit is 1/2 in. (1.3 cm). The nominal voltage is 63 kV. The deflector is 108 deg long. It is built of four segments, two in the outer high-voltage element and two in the inner ground element. The channel elements are water-cooled welded Inconel. Each of the two high-voltage elements is separately cantilevered from an insulating bushing. The whole assembly is built like a drawer. The floor of the drawer is a 1/2-in. sheet of K-Monel. Bearings throughout are Teflon-impregnated sintered bronze. A moving 1/4-scale model of the deflector elements is installed in the control room. It reproduces automatically all motions of the deflector in the cyclotron. The initial deflector is equipped with a standard metal fixed septum. A sawmill septum is being developed to replace the standard septum when and if desired. This sawmill septum consists of two metal rotating disks.