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Coaters sections are challenging to tune during the commissioning of a paper machine. This paper presents a detailed mechanical-electrical model of a one-coater section which includes a linear, operating point model of the sheet in the different spans, all the drivetrain components, and the vector controlled ac drives. The sheet model considers tail widening as well as the effect of coating and drying on the sheet elastic constant, activation of the torque current control and the beginning of coating. The developed model allows for complete evaluation of the different transient events including paper slack due to load impacts. Results show that the best performance of the drives is obtained operating the spans with even sheet tensions, which reduces and/or eliminates the operation of the drives in regeneration or braking zones.

J.A. Moral-Munoz holds a FPU scholarship (AP2012-1789) from the Spanish Ministry of Education., Citation classics offer an outlook on those papers that have attracted great and historical interest by a research community and that could be also considered the basis of the research field. A new approach, which is called H-Classics, has been developed to identify such highly cited papers. It is based on the H-index and is sensitive to both the own characteristics of the corresponding research discipline and its evolution. The present study provides a useful insight into the development of the intelligent transport systems research field, revealing those scientific actors (authors, countries, and institutions) that have made the biggest research contribution to its development., Spanish Government AP2012-1789

Many end users of rotating machinery equipment rely on coast-down and run-up vibration monitoring tests to analyze the vibration characteristics of a machine. However, if the user does not have a full understanding of these tests, the results can be misunderstood. This paper discusses, in depth, what these tests indicate and more importantly, what they do not indicate. It shows how a fundamental understanding of rotordynamics (natural frequencies and forced response vibration) is needed to make practical evaluations of rotating machine design and field performance.

The Runout of a shaft is defined as the deviation of the measured surface from an ideal circle rotating around its rotational axis. The total runout can be split into two main components: the mechanical and the electrical runout. The electrical runout depends on the metallurgical state of the shaft which can only be altered to a certain degree after the forging and heat treatment processes are finished. Especially large shafts for electric motors are prone for high electrical runout, because material imperfections are moved to the center of the shaft by the forging process. As there is an unfavorable ratio between bearing diameter and the largest diameter of the shaft, these imperfections will be in the area of the new shaft surface after machining. Statistics have proven that material inhomogeneity generating an electrical runout occurs in almost all kinds of steel. This paper will provide some information about how to eliminate uncertain material properties causing the electrical runout. One measure will be presented in detail including test results.

This paper introduces a microrobotic platform to make, manipulate and break individual paper fiber bonds. An individual paper fiber bond is the construction unit of a paper sheet and its properties affect the strength of the entire network of a paper sheet. In one hand, conventional laboratory tests on paper fiber bonds are mainly performed in a hand-sheet level. On the other hand, reported methods for paper fiber bond strength tests in individual bond level are either direct which are manual, laborious and have a low throughput or indirect which require data interpretation. The microrobotic platform presented in this paper performs direct and individual tests on paper fiber bonds. Making, manipulating and breaking individual paper fiber bonds are accomplished successfully demonstrating the first steps towards individual bond strength measurement.

The condensers influence on turbines thermal efficiency were researched in this paper. The optimization model for the system of condensers, turbines, cooling water and cooling water towers fan was proposed based on the basic model of turbines, condensers and cooling water. One paper mill power plant was taken as a case to verify the optimization model; the result showed that the optimization model was practical and useful for paper mill power plant.

In the context of rotating electrical machines, air gap is the physical separation between the rotor and stator core. The role of air gap is not as simple as first appears. Air gap design has evolved beyond uncomplicated mechanical distance into the consideration of a combination of various physical restrictions, electrical factors, and performance criteria. Various complex interdependent relationships and practical constraints are presented and evaluated.

Aiming at the disadvantage of insufficient heat supply of traditional heat pump system, this paper introduced a new kind of heat pump dry system for paper machine, which adopted the blowing steam control solution and a new control algorithm. This system improved the paper machinepsilas steam utilization ratio and automation lever, especially on the aspects of economizing on energy and sheet-broke treatment. This system also successfully solved the dry sectionpsilas condensate drain blockage problem. Proved through practice, it is worthwhile to popularize.

A method is proposed to predict the shape of a paper model of a three piece brassiere cup, which consists of several cloth and wire parts. Currently, the shape of each part is determined by creating a paper model and then refining the model. This process is repeated until the desired shape is achieved. However, predicting the 3D shape with a simulation would improve design efficiency. As a model is made of paper, each part is assumed to be inextensible and its surface is represented as combination of developable surfaces. The potential energy of a cup and geometric constraints imposed on the cup are formulated by use of the normal curvature and the direction of a generatrix of each developable surface. Minimizing the potential energy under geometric constraints derives a stable shape of the cup model. The computed and measured cup shapes coincided qualitatively.

The #2 Paper Machine at Sappi's Skowhegan, Maine Plant (USA) started up in September of 1986. It is a 300 inch wide coated free sheet paper machine driven by a 450 foot long lineshaft. Powering the lineshaft is a 4500 horsepower steam turbine. Due to an electrical power failure in 1996, the machine's lineshaft oversped and substantial damage occurred to the turbine's rotor and stator. This paper describes how five weeks of paper machine downtime was avoided by replacing the turbine with a 4000 horsepower electric motor.

Oil-impregnated paper bushing (OIP) is one of the key devices in transformer. Recently, several severely failure of OIP initiated explosion that destroyed large network transformers. A high expense of failures urged people to research the condition monitoring of the insulation defect of OIP. In this paper, the insulation defect of OIP is classified statistics based on the fault positions sourced by the CIGRE brochure and the China electric grid. Most bushing failures are caused by moisture entering the bushing through leaky gaskets or other openings. A comprehensive detection method which is combined the relative measuring method of dissipation factor with the partial discharge method for partial discharge of OIP is presented directing to the serious moisture defect of insulation moisture. It is applicable to the condition monitoring of insulation defect of bushings. It may be provide valuable reference for the condition monitor and maintain of OIP for the operation of the power system.

Recently, there has been strong interest in printed robots and paper electronics. Printing is an adequate manufacturing method for the mass production; robots manufactured by printing can be low cost, rapidly creatable and easy to design. Paper is one of smart materials with high water absorbency and strength; it is easily mass-produced at low cost. Many inexpensive and flexible devices were created in paper electronics. Therefore, we propose paper mechatronics that merges printed robots and paper electronics. We used a commercial ink jet printer with water-based ink for self-folding of paper; the paper was folded automatically along the printed line to make the robot body. The paper robot was equipped with a printed electrothermal actuator that consists of epoxy resin covered by conductive ink. The epoxy resin was heated by Joule heat of the conductive ink under a driving voltage of 8 V. The self-folding of experimental paper robot took 15 minutes to construct the body and the robot demonstrated a locomotion at 6.5 mm per step. I. INTRODUCTION

Lifetime of a transformer is determined by the condition of its oil paper insulation. Presence of moisture in the insulation reduces the dielectric strength and hence the remaining life. During the entire period of operation of transformer, moisture diffusion between oil and paper takes place, this causes the transformer to operate in a state of thermodynamic non equilibrium. Paper insulation of a transformer serves as the prime source of water in transformer. Oil moisture content can be directly measured using Karl Fischer Titration method. But determination of paper moisture will involve the collecting of paper sample from the transformer which will make the test destructive. Hence paper moisture is estimated from the standard equilibrium curves. Recently, pole values determined from the traditional linear model of the insulation structure have been used to serve as a basic guide for assessing the condition of oil paper insulation system of a transformer. Theoretically the RC branches of the linear equivalent model with lower time constant reflects the condition of insulation of oil and higher time constant branch reflects the condition of solid insulation. From this basic idea pole location of different branches are calculated and reported in this article. This present work attempts to assess the condition of insulation by locating position of the poles, and how pole locations vary with paper and oil moisture as well as temperature.

Cross cutter for paper or board is a facility that produces sheets of the desired length from a reel of web coming from the paper or board production line. Reliable operation, high speed of the web during cutting, and high accuracy of the sheet dimensions are common requirements. Mechanical assemblies of many existing machines are in good condition, offering possible extension of the service life, provided that drives and control system are modernized. The paper presents the characteristics and requirements of basic subsystems of the paper-board cross cutter from the control system perspective. Drag-link mechanism which provides the variation of the instantaneous speed of the cutter blades, necessary for proper operation of the cutter is described and analyzed. Experimental results obtained on a real, commercial paper-board cross cutter are presented in the paper. The results show that high accuracy of the sheet length can be achieved.

This paper introduces a microrobotic platform to manipulate and characterize individual paper fibers. Mechanical characterization of individual paper fibers determines the key parameters which affect the quality of paper sheets. Current laboratory tests are based on bulk paper fiber measurements. This paper presents a microrobotic platform which is able to characterize the flexibility of individual paper fibers directly, not in bulk amount and using indirect estimations. The flexibility of three different pulp samples is measured and the experimental results are reported.

Oil-paper insulation system is the most common insulation method of high-voltage apparatus. As the event of air-gap discharge can lead to aging and disruption of the insulation system, awareness of emergence and development of air-gap discharge in time could be helpful in finding internal latent fault of oil-paper insulation system. The paper does research on the air-gap discharge in the oil-paper insulation, and uses kernel principal component analysis method to reduce the dimension of statistical parameters and to extract new characteristic parameters. The sample signals at different times during the development process of discharge are adopted to cluster the new characteristic parameters. The air-gap discharge development process can be divided into four stages according to the information generated at different periods of the process combined with the clustering results. The four stages can be defined as: incipient discharge, developing discharge, constant discharge, pre-breakdown.

This paper presents an application that is designed to control the process of paper manufacturing in order to obtain a constant thickness for the resulting paper. The application teaches a system to control a thickness regulating member used in the manufacture of sheet products. The position of the slice lip is controlled by a number of actuators positioned along the slice lip and connected to it and to the head box. The system is composed of a Siemens S7–300 PLC connected to a Daytronic equipment. Also a TP270 operating panel is connected in order to allow users to view the state of the entire system and also set the position of the actuators.

Flow process line, producing honeycomb paperboard, installed a paper holder in general use. The paper holder is used to install fiber containers and provide continuous paper. Original paper holder is of low degree in automation and behindhand, which leaded low production efficiency, even destroyed paper. A new device of paper holder has been designed, which mainly depends on simulation software to design and control. Now the device had been adopted in product line of honeycomb paper processing.

This is an overview for proposing, writing, and presenting papers for the PCIC (Petroleum and Chemical Industry Committee) Technical Conference. It is intended to describe the process for proposing papers, and provide suggestions for writing and presenting papers at the PCIC Conference.

This paper introduced the structures of the common forms of packaging products, and introduced briefly the idea of finite element analysis and ANSYS. They are the key to solve the problem of this paper. This paper is based on this, and used the finite element analysis software ANSYS to static compression simulation analysis to the commonly used structure of paper-pulp model. Through the structural parameters of the study and analysis, this paper discussed the effects of the changes of the geometric angle and height on the limit pressure and the limit load of the model, and hoped to use research findings to provide a useful reference to the design of packing systems.

This paper deals with partial discharge measurements in oil-filled distribution transformers. Measurements are performed using antenna sensors, bearing in mind that these transformers are almost never equipped with bushing taps, so that alternative means for partial detection need to be devised. A simplified model is presented to investigate the emission pattern associated with partial discharge phenomena inside the transformer. The model is validated through measurements and computer simulations, and serves the purpose of designing an optimum sensor. Eventually, PD measurements on field on distribution transformers are discussed.

Heat tracing is most often associated with winterization of piping, tanks and instrumentation. As such, its role in a pulp or paper mill's preventive maintenance program can be easily understood. However, many year-round plant functions, some critical to plant operation, depend on proper heat tracing system performance. This paper addresses several aspects of heat tracing applications that deserve routine attention to improve the systems' overall performance and maintainability.

Paper insulated lead covered (PILC) cables provide the backbone of underground power distribution in the United States and other parts of the world. Efficient replacement of aged PILC is a looming challenge for the utility industry. Interdigital dielectrometry sensors that measure the dielectric properties of PILC cable are presented. Such sensors may be used to perform low cost health assessment of excavated cable samples. An overview of the theoretical groundwork is presented along with steady state and transient experimental results.

A numerical method that predicts the paper velocity at the roller transfer unit in an electrophotographic system is presented including the roller slip characteristics and the tension in the paper. The roller slip characteristics are derived from the measurement of the relative velocity between the roller and a paper under an external force. The paper feeding simulation is used to calculate the tension in the paper among the registration rollers, the roller transfer unit and the fuser rollers. The paper velocity at the roller transfer unit is predicted solving the equilibrium equations between the traction given by the transfer roller and the photoreceptor drum and the tension in the paper. The predicted velocities agree well with those from experiments, which is based on the time interval sensing of the pattern of lines printed on papers.

The load change of locomotive transformer used in the electric rail road is not smooth and regular. Its overload coefficient is also changeable, sometimes might be either zero or up to 3.0. The situation could cause the partial temperature rising in the transformer, extremely, the temperature, in short time, can be higher than 140/spl deg/C, even might reach 160/spl deg/C. It brings about new problems to the insulation of the transformer. Despite of having enough experience standard in the IEC which has been admitting, yet the thermal aging behavior of higher than 140/spl deg/C about oil-impregnated paper has not substantial experiment law to be abided by the designer and manufacturer. In this paper, some information is published about thermal aging characteristic of the oil-impregnated paper at 160/spl deg/C.

Oil impregnated creped kraft electrical insulating paper has electrical, mechanical and other characteristics which encourage its use in certain areas of oil immersed electrical insulation structures. While such applications are not necessarily novel, this paper presents the theoretical background and provides dielectric performance data for typical crepe paper insulation structures up to about 150 KV BIL. Specific dielectric performance data of these structures are presented as a function of the number of layers of creped paper and of the amount or degree of creping. Associated or resulting product design, product reliability, and other benefits are reviewed.

Insulation paper is primarily used in electric motors as slot cells, coil separators and phase insulation in integral horsepower equipment. The slot cell being defined as the basic ground insulation that provides mechanical and dielectric barriers from the magnet wire to the stator core. This definition emphasizes that the insulation paper forming the slot cell is mainly ground insulation.

Creped kraft paper covered magnet wire, when used in oil-filled transformers should give high impulse ratio, high impulse breakdown stress, and excellent AC breakdown stress.

Consideration is directed toward electromagnetic compatibility as viewed from the control aspect. Emphasis is placed upon an inter-system approach to the improvement of the over-all electromagnetic environment.

Since the early days of electricity supply (1890), impregnated paper based cables have been used for transmission and distribution purposes.1 Besides a long record of cable reliability, paper insulation has unique characteristics such as a ruggedness which provides easy taping and subsequent bending of the finished cable and a porous matrix which allows easy flow of the impregnant assuring a virtually void free composition with a high breakdown strength. However, the inherent electrical properties of the oil impregnated paper composition give rise to a limited power transmission capability for paper-oil insulated power cables at extra high voltage. This limitation has stimulated research on new transmission systems and new materials. This report is concerned with one of these efforts, namely, synthetic paper insulation.

In composite materials, the laminating industry has been built on the principle of locating things where they would do the most good. Way back in 1922 at General Electric Company I began to appreciate that the same base materials in the same proportions would give twice as much strength if they were disposed in laminate fashion than if they were randomly mixed. Throughout the years, these structures have been applied, originally to give greater strength and stiffness; but more recently through the whole gamut of qualities, to toughness and controlled permeation of films. Let me review some of those earlier days with you.

Fiber Modified Isomica provides the electrical design engineer the tools needed to overcome many critical insulation problems at a reasonable cost. The unimpregnated nature of the tape coupled with its physical strength makes it suitable for many taping applications previously not considered for reconstituted mica products. The very high mica content suggests a practical way of obtaining the reliability of mica insulation in a wide variety of rotating electrical apparatus.

Centre sealing process has been utilized in various assembling applications just as for basic holding. Be that as it may, to guarantee the procedure honesty for solid fixing is significant for higher efficiency, the utilization of robots and robotized frameworks is basic. A framework is depicted in which a robotized focus fixing framework is coupled together with the rollers to guarantee repeatable preparation. A workpiece might be carried on the single-pivot table. Wood pulp is made to roll over the rollers with the help of Brushless DC motor. The entire process is efficiently controlled by AT Mega 128 Microcontroller. Non oven sheets come through the rollers. The sealing process is achieved with the help of sealing paste and thermo compression process. It is being cut at the given dimensions of the non-oven sheets to the desired length and it is been disposed to the other end of the roller. The process continues until the desired products obtained. The proposed system is self-controlled and monitored by the controller.

In this paper, a 400kVA, 11/0.433kV Cast resin transformer (CRT) insulation system is considered for optimization. Due to its numerous advantages, the design and manufacturing technology for CRT is demanding, which can only be fulfilled if the design and manufacturing is free from any defects. The reliability and life of the CRT is defined by the life of its insulation system which is again a function of thermal and electrical stresses. To meet the allowable criteria for temperature rise is relatively an easy task for design engineers. Thus, within a window of 30 years, the reliability and life of CRT remains the function of electrical stresses only. Any activity of partial discharge (PD) in solid insulation leads to degradation of the solid insulation and premature failure. In the event of PD, time to failure depends on PD energy, PD resistivity of the materials and dielectric gap. Optimization of electric field and ensuring a void-free insulation system is must to avoid the premature failure of CRT. The electric field in CRT; more specifically, in high voltage winding depends on the electrical stresses in inter-layer insulation and end insulation. Insulation between two layers of high voltage winding is termed as layer insulation, whereas insulation between coils of high voltage wingdings and insulation to earth is termed as end insulation. At microscopic level, turns per layer (differential turns), insulation thickness between layers, and conductor radius decides the electrical stresses. Whereas for end insulation, the spacing between coils and coil-to-earth potential is deciding factor for electrical stresses. This paper addresses the design and analysis of inter-coil insulation system with finite element method (FEM) using 2D-ElecNet software by Infolytica Corporation. This software can be used for all types of electrostatic and electromagnetic analysis.

In this paper, we introduce the application of Japanese origami art to the floating system of unmanned helicopter model for the case of emergency landing. The “origami floating system” is integrated compactly in the helicopter and expands by an electronic controlled system when the helicopter lands on water. We tested our proposed floating system using three types helicopters, with the origami made from waterproof paper. The results indicate that the proposed system is feasible for helicopter and other aerial vehicles. In addition, several origami balls were constricted as floating devices for the helicopter. The correlation between the diameter of inflated ball and the size of origami paper sheet, along with the effects of the weight of helicopter on the water, are also investigated in detail.

The presence of condensate inside the dryer cylinders results in a significant increase in the power and torque required until the condensate transitions to the rimming stage. This paper evaluates the effect of the condensate during the starting of a dryer section using the experimental curves reported by several authors, as well as a dimensionless model of the input power as a function of the condensate quantity and roll velocity. Through the evaluation of a nine-cylinder dryer section for various condensate quantities and varying number of cylinders containing condensate, a comparison is made to the power requirements of several actual paper machine dryer sections undergoing various starting procedures. These comparisons indicate that if the percent condensate (condensate volume/full cylinder volume ×100) in the range of 0.5%-1%, or greater, is nominally assumed to be present, then the sizing of the section drive capacity must take into consideration the additional indrive load resulting from this condensate. Options are proposed to consider the effect of the condensate without increasing the Technical Association of the Pulp and Paper Industry recommended drive capacity of dryer sections.

With the urbanization thriving in China, electric cables are gradually replacing the overhead line and widely used in urban distribution grid. Meanwhile, fault rate of electric cables has increased in recent years. Owing to the harsh environment the electric cables worked at, most of them experienced high humidity, even immersion in water, which cause lots of practical problems. That is, inner layer of electric cables is easy to be damped, leading to insulation faults eventually. In this paper, a heating cycle voltage test platform was designed and three serious damp 10kV XLPE cables were selected. The heating cycle voltage test was used to heat the damp cables, evaporating moisture gradually. The variation of insulation resistance and dielectric loss tangent, due to the evaporation of moisture, was obtained by measuring these parameters during different periods of the heating cycle voltage test. With the heating cycle voltage test proceeding, the internal moisture of cable seeped from the place around the joint gradually and the insulation state was improved. Finally, an equivalent circuit model of damp cable has been proposed to qualitatively analyze the affects of moisture on the insulation of cable theoretically.

In this paper authors presented the research of textile electroconductive materials, which can be used to construction sensory textronic shirt to breath frequency measurement. The paper describes a method of measuring resistance of contact point and contact line of two electro conductive threads in textile knitted structures, which is known as transition resistance. This resistance is the input value to the modeling. The full paper also will be present some results of measurements carried out on unique measuring stands. The model of resistance connection in knitted structure in Matlab program will been also describe.

Insulation is a fundamental part of electric machines as it provides suitable electrical isolation between the different parts and sub-components. Developing techniques for analysing properties of insulation is extremely useful for the assessment of operating conditions, insulation quality and degradation (state of health). This paper investigates a novel non-invasive experimental approach to characterise phase-to-phase and phase-to-ground insulation by measuring electrical impedance and derived parameters (capacitance, dissipation factor) over a wide frequency range (100 to 2 MHz) at various different temperatures. Due to its simplicity the method lends itself better to an electrostatics interpretation compared with the typical twisted pair approach. Analysis is presented for the method which show its effectiveness under different operating conditions. This work has important applications in the area of condition monitoring of insulation using impedance based measurements.

The More Electric Aircraft (MEA), complete with the More Electric Engine (MEE) is a concept that has been introduced by aircraft and engine manufacturers to reduce the reliance on hydraulic and pneumatic systems while reducing fuel costs. However, these concepts have brought a requirement to increase system voltage which in turn challenges electrical insulation systems. The insulation system must withstand these higher voltages in more severe conditions such as the high temperature environment present in the engines. Electrical machines are critical on the more electric aircraft and the reliability of these machines must be high while the weight and volume are constrained. For MEE high temperature applications (up to 450°C), inorganic materials will be used as wire insulation since traditional organic materials cannot withstand such high temperature. Although inorganic insulation materials have been used for extended periods in other high voltage applications, their electrical behavior are not fully understood especially as part of aerospace electrical machine insulation system. This paper will detail the results of initial testing that seeks to understand the basic electrical performance of three inorganic wire candidates. The results will be used as a benchmark for further tests in order to evaluate critical ageing mechanisms for inorganic electrical machine insulation systems used in an aerospace environment. The performance of the electrical insulation used in all candidate wires is presented and compared. SEM scanning has been performed to examine differences in the insulation layer structures of the materials. Analysis has then been based on both measurement data and scanning results. All the tests have been performed before and after a limited number of thermal cycles and at the low pressure conditions i

Today rapid prototyping techniques make it possible to convert CAD models directly into paper laminated workpieces, plastic workpieces or metal sintered workpieces, but are restricted to dimensions of 500/spl times/500/spl times/500 mm. The robot, as a 6 to 8 axis milling machine, allows fast and economical manufacturing of high-volume workpieces of model materials. The robot may also be used as a tool for net-shape treatment, for grinding and for other surface treatments. Several examples of modeling and of tooling high volume workpieces, used in ship engineering and for paper production machines, in connection with the problems of calibration, of generating datas and the of graphical interactive operation are presented.

This paper based on the theory of transient electromagnetic method to establish the model of multi-layer columnar medium, deduce and solve the model, calculate the formation of the induced electromotive force. Through the software simulation, the different electrical parameters on the influence of the induced EMF were visually observed, which can determine the feasibility of the method, and provide a new method for the detection of residual oil.

This paper based on the heat generation of iron core and windings of transformers, makes a detailed analysis of production costs of iron core and load losses and the influence on top oil temperature and hot-spot temperature of transformers. It also explains clearly the meanings of parameters in winding hot-point temperature equation recommended by GB/T 15164-1994 Loading Guide for Oil-immersed Power Transformers. And adjustments and revisions are made on the winding index and oil and fat item to get more reasonable corresponding physical significance of them. At the end, a comparison is made between the recommended equation calculation results and improved equation in loading guide. Although there is a similar tendency of hot-point temperature of the two and the calculation results are not in great different, a more reliability is in improved equation.

Basic concepts and recent developments of HYDROMATRIXreg-technology for the exploitation of hitherto untapped low head hydro potential was presented. The installation of HYDROMATRIXreg-modules into existing dams is described as well as the cost benefits - compared to conventional turbine-generator-units - for the dam owner. Some of the physical laws governing the growth of hydro machinery are discussed and the regions of applicability of the technology are sketched. The permanent magnet excited synchronous StrafloMatrixtrade-unit was contrasted to the original concept employing directly driven induction machines in the full paper. Several examples of built HYDROMATRIXreg-plant are given.

The use of an oil-free design for 6kV power capacitors has not been realized previously, primarily from an economical point of view. Recently, however, the oil-free design is strongly recom mended for service entrance equipment in buildings and underground commercial facilities from the standpoint of fire prevention. Two insulation systems are feasible for the production of oil free power capacitors, a molded insulation system or a gas insulation system. Based on the resistance to thermal cycling, economy, and ease of handling, we selected the gas insulation system. This paper reports the results of various tests performed to select a dielectric system for high-voltage gas-insulated capacitors. A possible dielectric system for gas-insulated capacitors was considered to be one of the following: 1. CF-type capacitor; A roll of polypropylene (PP) film and alu minum foil, or 2. MF-type capacitor; A roll of metallized PP film.

In this paper, based on the concrete configuration of the medium voltage vacuum switch cabinet, the 3D mathematical model of electric field has been established for computing and analyzing the insulation performance. And the distributions of electric field at different locations and displacement angles have been obtained using finite element method (FEM). The locations of the maximum electric field strength and the weak insulation have been found. Moreover, by taking some improvement measurement has successfully solved the practical insulation problems.

A soft covered roll is deformed when nipped with a hard roll or another soft roll. This deformation affects the roll speed such that it must be accounted for in the regulation scheme. The deformation of the soft roll also has an effect on the torque distribution between the rolls in the nip. These applications are explained.