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DC reactor type superconducting fault current limiter (SFCL) has drawn the interest of some researchers in developing such device and more research work is being carried out in order to make it practically feasible. We have pointed out one issue that is not properly examined yet on such a device during load changing time. As we know, it is very difficult to introduce DC bias voltage to the reactor coil of the bridge type SFCL and some researchers are developing such device without using DC bias current. In such a case, the voltage drop occurs at the load terminal during the load increasing time caused by the DC reactor's inductance. By using the Electro-Magnetic Transients in DC systems which is the simulator of electric networks (EMTDC) software we carried out analysis of first few half cycles of the voltage and current waveforms after the load is increased. We also performed the same analysis for fault conditions. The peak value of the waveforms is considered in calculating the voltage drop at load terminal during the load changing time. The analysis can be used in selecting an appropriate inductance value for designing such SFCL.

The acoustic environment, as well as the length and speed of the train, determine noise and vibration levels. The average intensity of the noise (assessing by SEL) varies from 83.9 to 104.1 dB/A: the highest intensity accompanies the passing of express (average 95.32 dB/A); the lowest intensity is measured during the passing of EMU (average 89.24 dB/A). Vibrations of the highest intensity are measured during the passing through free fields (0.750 mm.sec-1). Regardless of the bridge type, the level of vibrations varies between 0.032 - 0.067 mm.sec-1.

Preliminary experiments have been performed on our proposed saturated DC reactor type superconducting fault current limiter (SFCL). The proposed SFCL is similar to a DC reactor type but an additional control winding is used. The DC bias current in the control winding saturates the core. The B-H curve of a magnetic circuit shows that low inductance value can be achieved in saturated region and high value in unsaturated region. The inductance of the saturated reactor depends on type of magnetic material, core size, number of turns and biasing conditions. The advantage of this type of SFCL over the existing DC reactor type is that, it shows low inductance value at normal operation and high value during fault time. On the other hand, the present DC reactor type SFCL shows a fixed value of inductance both in normal and fault time. In our experiment, we observed the inductance behavior of the saturated reactor by changing the control current. In order to make the work simple and convenient we have chosen a ferrite core. The experimental results are presented in this paper.

A micro-accelerometer is accomplished by use of a bridge-type structure with a flexible fixed-end beam. A PtFe layer is attached on the beam center surface as a magnetic field source. Giant Magneto-Resistance (GMR) material is used to detect magnetic field variation at different heights arising from the motion of the beam. An inverse numerical scheme is proposed to inversely obtain beam fixed-end boundary conditions, which are also the displacement of the detected object. This scheme employs the Laplace transform and applies numerical techniques to its inversion. Numerical verifications show the proposed scheme is accurate, stable, and tolerates errors arising from measurement, calibration and manufacture. Performance of this sensor is analyzed and sensors of other dimensions satisfying the prescribed performance requirements are designed by the proposed inverse analysis scheme.

The article considers the influence of the air gap size between the linear motor elements on the stability of the traction drive of the movement mechanism of the trolley of the bridge type crane. The main factors affecting the air gap size and the causes of their occurrence are described. The technique of calculating the magnitude of air gap variation is described in relation to the general deformation of the crane metal structure. Recommendations on the need for installation of additional equipment for load trolleys of various designs are given. The optimal values of the length of the trolley base are proposed. Observance of these values ensures normal operation of the traction drive.

In this study, bridge-type micro-hotplates (MHP) with an SU-8 supporting layer were proposed for smart gas sensor applications. The proposed MHP consisted of a heating membrane with an area of 140 µm × 140 µm, and a 33 µm-thick SU-8 layer deposited on its bridges. Finite element method based simulation confirmed that the proposed MHP displayed good thermal isolation properties. The proposed MHP was successfully fabricated, and the properties of the MHP were characterized. Current–voltage characteristics revealed that the MHP temperature can reach 550 °C at 5 V. The temperature of the MHP was calculated from changes in the resistance of the heater. Power consumption of the MHP approximately corresponded to 13.9 mW for heating to 300 °C. This was comparable to the power consumption reported in the previous studies. Furthermore, a stable operation under a constant voltage was observed for 100 min. The properties of the MHP indicated that it could potentially be utilized for applications related to integrated gas sensors.

Direct Digital Converter (DDC) suitable for resistive sensor elements connected in the form of bridge provides a digital output proportional to quantity being sensed. However, such a DDC requires that all the four sensor elements are to be identical. If there is a mismatch between the sensor elements (nominal values of the four resistances not equal) the error in the output of the DDC increases drastically. We now present a modified DDC that can tolerate mismatch between the four sensing elements of a bridge type resistive sensor. While the worst case error observed from the conventional DDC scheme rises from ± 0.07% to ± 1.32 % (simulation studies) for a very low mismatch of 0.03 %, the worst case error observed from the improved DDC scheme proposed here is only ± 0.24%.

The cable-stayed bridge belongs to a typical multi-degree-of-freedom system which has complicated vibration characteristic. The seismic performance of the cable-stayed bridge cannot be estimated by classic pushover analysis methods because of the great effects of higher modes on it. The principal objective of this investigation is to propose a displacement-and-adaptive-spectra-based pushover analysis procedure (DASPA) which is based on inelastic displacement response spectra. The contributions of higher modes to response and the redistribution of inertia forces because of structural yielding and the associated changes in the vibration properties of the structure are considered in the procedure. According to the special bridge type for cable-stayed bridge, the post-yield displacement pattern is modified to approach practice (MDASPA). The seismic performance determined by DASPA and MDASPA is compared with nonlinear RHA procedure. The results indicate that the MASPA procedure provides more superior accuracy in estimating seismic performance for structures compared with DASPA procedure.

Full-scale data on the natural frequencies and the damping ratios of 114 highway bridges in China, and the dynamic characteristics monitoring data of four bridges under ambient excitation, have been collected and analyzed. The data indicate that the natural frequencies of the long-span bridges have power function relationships with the lengths of the main spans, whereas the damping ratios of the bridges scatter with the influence of the width of section, the piers, the material, the test environment, and the bridge type. Values of the damping ratios of different bridge types in China are proposed based on the collected data. With the increase in service ages, the natural frequencies of the bridges change little, whereas the damping ratios of the bridges decrease and tend toward stable after certain years. The forms of damage, the locations of damage, and the strengthening methods have a great influence on the changing of damping ratios.

Bridge-type inverted siphon is located at Yangdong reservoir in the Zixing county, Hunan province, its controlled basin area is 31000 mu. Inverted siphon pipe is single round pipe, inner diameter is 1.0 m, wall thickness is 0.21 m, adopts reinforced concrete structure. This paper uses universal finite element software to analyse bridge-type inverted siphon, and research stress and deformation distribution of inverted siphon during construction and operation period. Research results further verify rationality and safety of design scheme, can reliable reference basis for design and construction of inverted siphon structure. Analysis results show that, stress of bridge type inverted siphon is small, through reinforcement can meet design needs and strength requirement. Displacement of inverted siphon structure is small, can satisfy stiffness requirement. Analysis shows that inverted siphon structure is reasonable, safe and reliable.

The paper deals with the analytical estimation of bandwidth and device sensitivity of cantilever- and bridge-type monolithic piezoresistive and capacitive accelerometers using different beam models and of their design sensitivity due to the change of geometrical parameters. Using a simplified two-beams model, closed-form formulae have been derived to give the relationship between the rates of length, width and thickness of the beams and the lowest eigenfrequency characterizing the bandwidth as well as the physical sensitivity of the accelerometers. By means of symbolic derivation, a structural design sensitivity analysis has been carried out to obtain information for the optimal selection of the geometrical parameters.

In order to improve the luminous efficiency in ac PDP(Plasma Display Panel), we have suggested a new bridge type sustaining electrode which makes it possible to have free alignment between front and rear panels. The luminous efficiency of the ac PDP with suggested new sustaining electrode is improved by about 28 % compared with that of conventional sustaining electrode. However, the luminance of the ac PDP with the suggested electrode is kept the same with the conventional ones.

In high power applications, the fault current limiter has been discussed for many years because of some limitations of conventional circuit breakers. Many types of fault current limiter have already been introduced in papers. In this work, a simple bridge-type fault current limiter has been designed and constructed. The performances of the limiter have been tested successfully. In the bridge-type current limiter, a DC reactor appears in the line when the connected load is increasing. This causes a voltage drop across the load terminal during load changing. The DC reactor effect of the current limiter has been studied. Some experimental results regarding the reactor effect of the limiter have been considered and compared with the results obtained from computer simulation.

In order to improve the luminous efficiency of ac plasma display panel (PDP), a new bridge type sustaining electrode is suggested. The luminous efficiency of the ac PDP with suggested new sustaining electrodes is improved about 30% compared with that of conventional sustaining electrodes. Furthermore, the suggested ac PDP is maintained almost the same luminance with the conventional ones, and this type has a merit of free alignment between front and rear panels.

The acoustic environment, as well as the length and speed of the train, determine noise and vibration levels. The average intensity of the noise (assessing by SEL) varies from 83.9 to 104.1 dB/A: the highest intensity accompanies the passing of express (average 95.32 dB/A); the lowest intensity is measured during the passing of EMU (average 89.24 dB/A). Vibrations of the highest intensity are measured during the passing through free fields (0.750 mm.sec−1). Regardless of the bridge type, the level of vibrations varies between 0.032 – 0.067 mm.sec−1.

We report a rare case of stenotic double-orifice mitral valve of incomplete bridge type in a 40-year-old male. The fibrous bridge tissue between the leaflets was successfully split with a 24-mm Inoue balloon catheter using the stepwise dilation technique. Cathet. Cardiovasc. Intervent. 49:200-203, 2000.

In 1995, the great Hanshin-Awaji earthquake caused a large amount of destruction and structural failures. One example, whose mechanism is not fully clear, is the fracture of a bridge bearing of a Nielsen type bridge that does not occur under the ordinary static or dynamic loading conditions. The fracture probably resulted from very high stress due to an unexpected dynamic mechanism. In this paper, the 3-dimensional dynamic behavior of a Nielsen type bridge was analyzed by assuming a collision between the upper and the lower parts of the bearing, which might have occurred in the great Hanshin-Awaji earthquake. The numerical results show that an impact due to a relative velocity of 5∼6m/s between the upper and the lower parts of the bearing generates a stress sufficient to cause a fracture in the upper bearing. The observed features of the actual fracture surface was also simulated fairly closely.

The purpose of this study was to investigate the accuracy of interocclusal recording addition-type silicone rubber impression materials that reproduced intercuspation on mounting stone casts. A bridge type reference model, which could not maintain stable intercuspation without interocclusal records, was selected. The reference model was mounted on an articulator. Interocclusal records were taken on the reference model. The reference model could be separated from the articulator when interocclusal records were measured. For interocclusal records which were made from PRESIDENT JET BITE, EXABITE, Stat·BR, BITESIL, MEMOSIL, and MUSHPRINT between the upper and lower reference models, the occlusal heights of the reference model on the left molar of the abutment side, anterior teeth, and right molar were measured using an IP-Checker. In addition, the relationship of the reproducibility of intercuspation and the mechanical properties of materials was studied.The results were as follows:1. The occlusal height on the left molar was high; the occlusal height on the anterior teeth and the rightmolar were unchanged or low when the recording range was on the abutments. The occlusal height on the left molar and the anterior teeth were high; the occlusal height on the right molar was unchanged when the recording range was 1/3 of the dentition.2. The reproducibility of intercuspation of the interocclusal recording addition-type silicone rubber impression materials was excellent; however, MEMOSIL was inferior to the other materials. The occlusal height on the anterior teeth was greatly influenced by the recording range when BITESIL and MEMOSIL were used.3. It was surmised that the reproducibility of intercuspation was influenced by the compression set and the dimensional change of the interocclusal recording addition-type silicone rubber impression materials.

This paper presents the development of a new compact three-axis compliant stage employing piezoelectric actuators and a new flexure structure. A proposed stage works out-of-plane (Z, θx, θy) direction. The stage consists of 4 amplification flexures mounted piezoelectric actuators. New structure of flexure reduces height and enhances dynamic performance of stage. To certify excellent performance of the stage, comparison accomplished between conventional amplification flexure and new compact bridge type flexure. Modeling and optimal design of new type nano positioning stage performed. The optimal design is executed on the geometric parameters of the proposed flexure structure using Sequential Quadratic Programming. Experiments are carried out to verify the static and dynamic performance of the stage. The proposed out-of-plane nano-positioning stage has a Z-directional motion range 190 μm and a θx, θy-directional motion range ±2 mrad. The resolution of the stage is 4 nm, 40 nrad, and 40 nrad in the Z-, θx-, and θy-directional motions, respectively. The size of stage is 150 × 150 × 30 mm(3).

近年, 環境問題は世界的な関心を集めており, その研究が進められているが, 土木・建築の分野においても, 環境負荷に対する検討を行う必要がある. 本研究では, 橋梁架設時における環境負荷に対する評価も行えるように, エネルギー消費量及びCO2排出量の算出を行える橋梁形式選定支援システムを開発した. また, 本システムを用いて各橋種の環境負荷を算出し, その比較を行い, 現在の橋梁建設においてどの部分が最も大きな環境負荷を与えているかを示すとともに, どの橋種が環境に大きな負荷を与えているかを算出している. さらに, リサイクルを行うことによってどの程度環境負荷値を抑えられるかについても検討している.

Merged epitaxial lateral overgrowth (MELO) of silicon has been used to form 10 μm ± 0.5 μm thick, 420 μm long, and 170 μm wide single-crystal silicon beams for a four-bridge piezoresistive accelerometer. Buried SiO2 stripes are used to produce the near-perfect backside etch-stop for the silicon membrane, while the topside thickness control is established by the growth rate of 0.1 μm min−1. The MELO membrane technique produces an accelerometer that has low-doped high-quality single-crystal silicon beams. The measured sensitivity is 287 μV V−1 g−1, which is about twice that for a similar device, and the non-linearity is less than 4% up to 30g of acceleration.

The purpose of this study was to investigate the accuracy of interocclusal recording materials that reproduced intercuspation. Two types of stone casts for measuring were selected and mounted on the verticulator. One stone cast (Crown type) that was prepared for a single crownmaintained stable intercuspation. Another stone cast (Bridge type) that was prepared for a fixed partial denture could not maintain stable intercuspation. For interocclusal records, which were made from President Jet Bite, Exabite, Ramitec, Xanthano, Impression Paste and New Plastone between the upper and lower stone casts, the occlusal heights of the stone casts on the left molar of the abutment side, anterior teeth and right molar were measured using an IP-Checker. The President Jet Bite, Exabite and Ramitec elastic materials were studied to determine the influence of the recording extents.The results were as follows:1. The occlusal height of both stone casts was higher for the left molar and the anterior teeth than for the right molar.2. The occlusal height of the Bridge type was higher than the Crown type.3. The results suggest that interocclusal records made from addition type silicone impression materials have the best reproducibility of intercuspation and a smaller recording range has greater reproducibility of intercuspation.

We report a hierarchical piezoelectric tripod manipulator based on a reverse bridge-type displacement amplifier. The reverse bridge-type amplification mechanism is pre-strained by each piezo-stack actuator up to 60 μm and is cross-stacked in a series arrangement to make a compact and high-stroke manipulator having load-bearing characteristics. The designed manipulator with three degrees of freedom is compact with a height of 56.0 mm, a diameter of 48.6 mm and total weight of 115 g. It achieves a translational stroke of up to 880 μm in heaving motion and a tilting angle of up to 2.0° in rotational motion within the operating voltage and power range of the piezoelectric stack actuator. A key feature of the present design is built-in and pre-strained displacement amplification mechanisms integrated with piezoelectric stacked actuators, resulting in a compact tripod manipulator having exceptionally high stroke and load-bearing capacity.

The initial content of this paper presents results of a survey-based study that identified simplified displacement monitoring of railroad bridges under trains as the main research interest of railroad bridge structural engineers. The second part of this publication describes a railroad bridge classification towards structural health monitoring (SHM) applications, based on current structural engineering problems and challenges identified by the railroad industry for each railroad bridge type. Finally, this paper briefly describes ongoing research related to attempting to monitor railroad bridge deflections by means of using simplified wireless sensors, and preliminary field experimentation and proof of concept validations.

Aim It is the aim of this paper to consider the factors associated with the need for re-intervention on a conventional or resin-retained bridge, excluding recementation. Methods A data set was established consisting of patients, 18 years or older, whose birthdays were included within a set of randomly selected dates, one of which was chosen in each possible year of birth and whose restoration records contained the placement of one or more indirect restorations on courses of treatment with last date on the claim form after 31st December 1990, and with date of acceptance after September 1990 and before January 2002. For each patient treated with a bridge, the subsequent history of intervention on each tooth used as a bridge abutment was consulted, and the next date of intervention, if any could be found in the extended data set, was obtained. Thus a data set was created of bridge abutments which have been placed, with their dates of placement and their dates, if any, of re-intervention. Results Data for over 80,000 different adult patients were analysed, of whom 46% were male and 54% female. A total of 7874 abutments (6800 conventional and 1074 resin-retained) were obtained from the data over a period of eleven years. Factors which were found to reduce outcome of bridges included type of bridge, patient payment exemption status, patient attendance pattern and position of the bridge in the patient's mouth. Conclusions Survival of conventional bridge abutments has been shown to be 72% at 10 years, this being similar survival time to crowns. Various patient factors and bridge type were also found to influence survival.

We discuss long-term dynamical behavior of the solutions for the nonautonomous suspension bridge-type equation in the strong Hilbert spaceD(A)×H2(Ω)∩H01(Ω), where the nonlinearityg(u,t)is translation compact and the time-dependent external forcesh(x,t)only satisfy condition (C*) instead of translation compact. The existence of strong solutions and strong uniform attractors is investigated using a new process scheme. Since the solutions of the nonautonomous suspension bridge-type equation have no higher regularity and the process associated with the solutions is not continuous in the strong Hilbert space, the results are new and appear to be optimal.

In recent years, superconducting fault current limiter (SFCL) has become one of the forefront topics of current-limiting technology in the world. In this paper, the structure and working principle of several SFCLs which perform high in the actual power grid, such as resistance type, reaction type, hybrid type, magnetic shielding type, saturated iron core type, bridge type, active type and three-phase circuit reactance type. Through the analysis of the advantages and disadvantages of the SFCLs, the reference for further study of the SFCLs is provided.

The Omura Bay is situated in the central part of Nagasaki Prefecture, which yields many problems including traffic one between both the northern and southern parts and the eastern and western parts of the Prefecture.In this paper the authors proposed a concept of the Omura Bay Bridge in order to solve these problems, and considered on the concept from engineering point of view. Discussions werefocused on environmental, bathymetric and soil surveys, route location, bridge type and others. As the type of bridge, a pontoon type was considered to be more prominent than the other types owing to its working period and cost shortage, and if this type bridge were built here the Omura Bay Bridge will be welcomed to be a tourist route as the first one in this type in Japan.

The test of suspender tensioning force of suspender arch bridges is the key technology during construction stage and service stage of this bridge type. Calculation of suspender tensioning force based on measured natural frequency is the most beneficial and convenient method at present. Starting with basic principle of suspender vibration, influencing factors during the testing process of suspender tensioning force are analyzed in this paper. And based on existing research results, a test method of suspender tensioning force with high precision basis on vibration test is formed. Finally, relying on a suspender arch bridge, the formed method is verified.

Cable tension adjustment of suspender arch bridges is the key technology during the construction stages of this bridge type. Nowdays, there are some disadvantages of different degrees in commonly used cable tension monitoring methods during cable tension adjustment stage of suspender arch bridges. Therefore, the cable tention monitoring method of suspender arch bridges during cable tension adjustment basis on neural network algorithm is proposed. Strain and displacement in specific sections of arch ribs and stiffening girders are taken as input data in this method. While the cable tension is taken as output data. During the cable tension adjustment stage of suspender arch bridges, it only needs to collect the strain and displacement in specific sections, in order to analyze the cable tension. Finally, relying on a suspender arch bridge, the formed method is verified.

As pattern size becomes smaller, requirement for defect reduction is getting higher and higher. It is known that defects occur in various steps of lithography process. In this study, we focus on defects related to the resist dispense system. Of those defects, the most typical is bridge type defect which caused by foreign substances contained in resist film. The source of those is considered to be insoluble substances, such as resist gels, in resist liquid. So far, the conventional countermeasure has been the development of resist line filters (optimization of materials, shrinking of pore size, and so on). But, according to the recent reports and our experimental result, we can say that not only filter type but also filtration condition has certain influence on bridge type defect generation. In this study, we examine the influences of resist dispense system and its parameters on bridge type defect generation. This paper provides some experimental data and introduces our approaches to the optimization of resist dispense system and its effects.

Bridge type loops–water source heat pump with 4 functions that has bridge type connecting multi–loops, is made up of condenser, evaporator, fan coil unit, hot water tank, indirect heat exchanger and so on 5 hot equipments, by using the connection way of the bridge circuit and 5 pairs of control nodes and 4 T–valves to connect user terminals and water source; in order to control the change of water circulation in multi–loops, and to realize heating, air conditioning, hot water, air conditioning + hot water 4 functions.

The aim of this paper is to present two different types of MEMS switch structures developed in IMT: bridge and cantilever. For these two configurations were chosen different length of bridges and cantilevers; also, for the actuation pads used were considered different size. Finite Element Method simulations were performed in order to determine the pull-in voltage. Comparison between simulated and measured results will be presented for the bridge type switch structure.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This summary paper is a condensation of a full report which containns information on over 40 bridge projects in North America. The paper gives design, production and erection considerations, and other details for many of these bridges. It also includes a fully worked example of preliminary design of a 350 ft (106 m) long overpass, made of two equal spans. The example calculations are done by a handheld calculator without need for any specialized computer facility. Also included is reference to a PC-based computer software for detailed time-dependent analysis of this bridge type.

Double-orifice mitral valve is an uncommon anomaly of the mitral valve with a single fibrous annulus with 2 orifices opening into the left ventricle. Three major types of this anomaly are recognized: (1) the eccentric or hole type (accounting for about 85%), (2) the central or bridge type (about 15%), and (3) duplicate mitral valve, which involves 2 mitral valve annuli and valves, each with its own set of leaflets, commissures, chordae, and papillary muscles. However, some echocardiographic artifacts also may lead to interesting appearances. The duplicating of cardiac valves by refraction of the ultrasound beam or mirror images has rarely been reported. The authors present the duplication of a moving mitral valve associated with an echocardiographic refraction artifact.

A novel bridge type optoelectronic (OE) sample and hold circuit based upon current steering is presented for the first time and experimentally tested. Comparison between this circuit and a more conventional or direct OE sample and hold circuit which draws charge directly from the signal source shows that the bridge type is clearly superior in performance to the direct OE circuit. When a high speed signal is to be sampled with considerable precision, the bridge type OE sample and hold circuit offers high charging capability, much needed isolation, and reduced time jitter, distinct advantages over electronic sample and hold circuits. >

A novel three phase bridge type solid state fault current limiter (SSFCL) with coupling transformer has been developed, which can be operated in bi-directional current condition (such as operated in linking bus). The operation principle of the SSFCL and its control strategy are discussed in this paper. Problems raised especially in the bi-directional current condition are studied in detail. The performance of the SSFCL is verified through simulation and testing.

The stability properties and dynamic performances of the Hechang Bridge, which is a concrete filled steel tubes (CFST) arch bridge in Fujian, China are examined in this paper. The differences of stability and dynamic performance between basket type arch rib and parallel type arch rib are also discussed using three-dimensional finite element models. Furthermore, the influence of inclined angle for basket-type arch rib on stability and dynamic performance is also studied in this paper. It can be used for reference of similar bridges in selecting the bridge type, the bridges main structures, and the static and dynamic analyses that need to be performed.

National Bridge Inventory (NBI) data for bridges built from 1950 to 1987 were used to identify the 12 most common bridge types. Three of these types account for almost half of the bridges built in the United States during that period but have the highest percentages of structural deficiency as classified by Federal Highway Administration (FHWA) criteria. Many timber stringer and steel stringer bridges built during the 1980s already are classified as structurally deficient in the 1987 NBI. The most common deficiency on interstate bridges is the deck, whereas the most common deficiency on county bridges is the substructure. On the average, in a given state, the three most common bridge types account for two‐thirds of all bridges built within that state during the period 1950–1987. Data for six selected states show considerable variety in types of bridges built, percentages classified structurally deficient, and the most common deficiencies. Data for two adjacent states indicate differences in bridge perform...

A novel bridge type FCL (fault current limiter) with single controllable switch is proposed in this paper. The topologies and control strategies of the new FCL for single-phase and three-phase power systems are investigated in detail. The advantage of the new FCL includes simplicity in circuit and control method, low cost and high reliability. Simulations based on Psim 6 are carried out. A three-phase experimental model is constructed. Simulation and experiment results proved the validity of the new FCL.

A novel bridge type FCL (Fault Current Limiter) with single self-turn-off device is proposed in this paper. The topologies and control strategies of the new FCL for single-phase and three-phase power systems are investigated in detail. The advantage of the new FCL includes simplicity in circuit and control method, low cost and high reliability. Simulations based on Psim 6 are carried out. A three-phase experimental model is constructed. Simulation and experiment results proved the validity of the new FCL.

This paper reports on design, simulation and manufacturing of a novel millimeter wave MEMS switch structure. The switching operation utilize electrostatic force ? which was the only way for high reliability and wafer scale manufacturing techniques at high frequency. The switching element, a bridge type one, shows an actuation voltage of about 24.5V. Different geometries for the switching element were designed and manufactured. The switches exhibit low insertion losses (0.75dB@60GHz) with good isolation (>50dB@60GHz). The simulated and measured results were in a good agreement for the 60GHz frequency band.

A novel IGCT-based half-controlled bridge-type Fault Current Limiter is proposed in this paper. By substituting the half-controllable SCR in the rectifier bridge with self-turn-off device IGCT, the uncontrolled time of the Converter Bridge can be reduced from half a cycle to the delay time of the current measuring circuit. If the maximum current in the dc reactor is preset, the inductance, volume, weight and cost of the DC reactor can be reduced to one 32th of what it is in the SCR-based bridge type FCL in three phase power systems approximately. The magnetization time of the DC reactor is reduced. The control method is very simple. The dynamic performance of the proposal FCL can be improved. Topology and control strategies of the proposal FCL are described in detail. Simulations under each short circuit fault mode are carried out. An experimental model is constituted and tested. Simulation and experiment results proved the practicability and validity of the new FCL.