The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
A.f. Holland - One of the best experts on this subject based on the ideXlab platform.
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Behaviour of solid state technology in transient and Surge Protection systems
IEE Colloquium on Lightning and EMC, 1996Co-Authors: A.f. HollandAbstract:The purpose of this document is to discuss the various solid state technologies in popular usage, and as the basis of Surge Protection modules employed to protect sensitive equipment from transient and Surge overvoltages. The terminology's, behaviour and selection of such devices can lead to confusion when seeking a solution to a specification need such as BS6651, IEC 801-5 etc. and most importantly to satisfy the actual application requirement. (8 pages)
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Behaviour of solid state technology in transient and Surge Protection systems
IEE Colloquium on Lightning and EMC, 1996Co-Authors: A.f. HollandAbstract:The purpose of this document is to discuss the various solid state technologies in popular usage, and as the basis of Surge Protection modules employed to protect sensitive equipment from transient and Surge overvoltages. The terminology's, behaviour and selection of such devices can lead to confusion when seeking a solution to a specification need such as BS6651, IEC 801-5 etc. and most importantly to satisfy the actual application requirement.
Francois D. Martzloff - One of the best experts on this subject based on the ideXlab platform.
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Update on a Consumer-Oriented Guide for Surge Protection | NIST
1999Co-Authors: Francois D. Martzloff, D. Nastasi, K. O. PhippsAbstract:Caught among contradictory stories on the need for Surge Protection as well as unsupported anecdotes of Surgerelated failures found in some editorial advertising, the typical consumer is in a quandary on how to best allocate personal resources to protect the expensive electronic equipment found in a modern household. To help provide some answers to this quandary, a team of experts had previously developed a basic engineering Recommended Practice on Surge Protection of residential electronics. The value of the theoretical concepts presented in the Recommended Practice is illustrated by two case histories where such concepts were not applied. In addition, “post mortem” examinations have been performed on appliances turned in as having failed as a result of a lightning Surge. Those appliances that were in fact not damaged by lightning, although part of a claim settlement, were tested for Surge immunity.
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Coordinating cascaded Surge Protection devices: high-low versus low-high
IEEE Transactions on Industry Applications, 1993Co-Authors: Francois D. MartzloffAbstract:Cascading Surge Protection devices located at the service entrance of a building and near the sensitive equipment are intended to ensure that each device shares the Surge stress in an optimum manner to achieve reliable Protection of equipment against Surges impinging from the utility supply. However, depending on the relative clamping voltages of the two devices, their separation distances, and the waveform of the impinging Surges, the coordination may or may not be effective. Computations with experimental verification of the energy deposited in the devices for a matrix of combinations of these three parameters is provided. Results show coordination to be effective for some combinations and ineffective for some others, which is a finding that should reconcile contradictory conclusions reported by different authors making different assumptions. From these results, improved coordination can be developed by application standards writers and system designers.
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Coordinating cascaded Surge Protection devices: high-low versus low-high
Conference Record of the 1991 IEEE Industry Applications Society Annual Meeting, 1991Co-Authors: Francois D. MartzloffAbstract:Cascading Surge Protection devices located at the service entrance of a building and near the sensitive equipment are intended to ensure that each device shares the Surge stress in an optimum manner to achieve reliable Protection of equipment against Surges impinging from the utility supply. However, depending on the relative clamping voltages of the two devices, their separation distance, and the waveform of the impinging Surges, the coordination may or may not be effective. The authors provide computations with experimental verification of the energy deposited in the devices for a matrix of combinations of these three parameters. Results show coordination to be effective for some combinations, and ineffective for some others, a finding that should reconcile contradictory conclusions reported by different authors making different assumptions. From these results, improved coordination can be developed by application standards writers and system designers.
Lance Warren Russell - One of the best experts on this subject based on the ideXlab platform.
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dynamic Surge Protection an approach to handling unexpected workload Surges with resource actions that have lead times
Distributed Systems: Operations and Management, 2003Co-Authors: Ed Lassettre, David Wiley Coleman, Steve Froehlich, Lawrence S Hsiung, Todd W Mummert, Mukund Raghavachari, Geoffrey Parker, Yixin Diao, Joseph L Hellerstein, Lance Warren RussellAbstract:Today’s information technology departments have significantly varying demands for resources due to unexpected Surges in subscriber demands (e.g., a large response to a product promotion). Further complicating matters is that many resource actions done in response to Surges (e.g., provisioning or de-provisioning an application server) have substantial delays (lead times) between initiating the resource action and its taking effect. This paper describes dynamic Surge Protection, an approach to handling unexpected workload Surges in systems that have lead times for resource actions. Dynamic Surge Protection incorporates three technologies: adaptive short-term forecasting, on-line capacity planning, and configuration management. The paper includes empirical results from evaluations done on a research testbed, including favorable comparisons with a threshold-based heuristic. The results from an extended test also show that service objectives can be maintained cost-effectively.
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DSOM - Dynamic Surge Protection: An approach to handling unexpected workload Surges with resource actions that have lead times
Self-Managing Distributed Systems, 2003Co-Authors: Ed Lassettre, David Wiley Coleman, Steve Froehlich, Lawrence S Hsiung, Todd W Mummert, Mukund Raghavachari, Geoffrey Parker, Yixin Diao, Joseph L Hellerstein, Lance Warren RussellAbstract:Today’s information technology departments have significantly varying demands for resources due to unexpected Surges in subscriber demands (e.g., a large response to a product promotion). Further complicating matters is that many resource actions done in response to Surges (e.g., provisioning or de-provisioning an application server) have substantial delays (lead times) between initiating the resource action and its taking effect. This paper describes dynamic Surge Protection, an approach to handling unexpected workload Surges in systems that have lead times for resource actions. Dynamic Surge Protection incorporates three technologies: adaptive short-term forecasting, on-line capacity planning, and configuration management. The paper includes empirical results from evaluations done on a research testbed, including favorable comparisons with a threshold-based heuristic. The results from an extended test also show that service objectives can be maintained cost-effectively.
Nihal Kularatna - One of the best experts on this subject based on the ideXlab platform.
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Surge Protection Standards and Practices
Design of Transient Protection Systems, 2019Co-Authors: Nihal Kularatna, Alistair Steyn Ross, Jayathu Fernando, Sisira JamesAbstract:Abstract Given an overview of power quality issues and background to the simple circuit concepts used in designing Surge Protection systems in Chapter 1, this chapter discusses the standards and practices used in developing and testing Surge protector devices (SPD). Transients discussed in this book are short-duration, high-amplitude (positive or negative) and generally nonrepetitive signals superimposed on the AC or DC power supply inputs. In general, transients that get induced on the equipment inputs could be due to several different reasons, such as inductive switching, lightning, electrostatic discharge, or electromagnetic pulses. All these are very unpredictable random occurrences. Electrostatic discharge may occur due to build up of static charge on the human body with voltages as high as 20,000 V. These can generate transients with rise times as fast as 2 kV/ns. Electromagnetic pulses due to nuclear activities where gamma rays could be released can cause transients with rise times around 5 kV/ns, while lightning activity-related transients can generate signals with rise times around 600 V/ns. Given the statistical nature of these different types of transients, SPD developers and manufacturers are guided by a set of standards and practices as summarized in this chapter.
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A supercapacitor based enhancement technique for stand-alone Surge Protection circuits
Industrial Electronics (ISIE), 2013 IEEE International Symposium on, 2013Co-Authors: Jayathu Fernando, Nihal KularatnaAbstract:With the International Technology Roadmap for Semiconductors predicting below-25nm feature-size VLSIs, powered by DC power supplies of less than 1V, Protection against transients has become mandatory for modern electronic systems. Surge Protection circuits are usually designed using non-linear devices such as metal oxide varistors and semiconductor devices and these devices are rated for short-term energy absorption, based on transient waveforms defined by standards such as IEEE C62.41. Despite their very low voltage DC ratings, supercapacitors are characterized by large time constants and significant continuous energy absorption ratings. This paper presents details of a patent-pending technique where multi-winding magnetic core with a supercapacitor based energy absorber stage can be combined with the commonly used non-linear devices, for enhanced Protection. Comparison of the supercapacitor-enhanced circuit together with a commercial Surge Protection circuit is provided.
Liann-be Chang - One of the best experts on this subject based on the ideXlab platform.
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Improved Surge Protection of flip-chip gallium nitride-based HEMTs by metal-semiconductor-metal two-dimensional electron gas varactor
2014 International Symposium on Electromagnetic Compatibility Tokyo, 2014Co-Authors: Liann-be Chang, Chien-fu Shih, Tung-wuu Huang, Chu-yeh Tien, Ping-yu KueiAbstract:AlGaN/GaN high electron mobility transistor (HEMT) was designed with improved Surge Protection characteristic through the use of a MSM-2DEG varactor connected in series to the gate of HEMT. Under an ESD Surge stress of 1100 V or below, the HEMT incorporating this Protection feature doesn't exhibit any change because the Surge stress can be directly blocked by the MSM-2DEG varactor. Furthermore, flip-chip (FC) technology was also used to further improve the thermal performance and reliability of HEMTs. The heat generated in the two-dimensional electron gas (2DEG) channel of HEMT flows directly through the interconnect metal to the submount, and hence improve the thermal conduction. Based on these results, the proposed flip-chip HEMT with MSM-2DEG varactor can effectively improve the Surge Protection characteristics.
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Improvement of Surge Protection by Using an AlGaN/GaN-Based Metal–Semiconductor–Metal Two-Dimensional Electron Gas Varactor
Japanese Journal of Applied Physics, 2012Co-Authors: Yi-cherng Ferng, Liann-be Chang, Chun-yu Cheng, Ping-yu Kuei, Lee ChowAbstract:In this paper, a varactor with metal–semiconductor–metal diodes on top of the (NH4)2S/P2S5-treated AlGaN/GaN two-dimensional electron gas epitaxial structure (MSM-2DEG) is proposed to the Surge Protection for the first time. The sulfur-treated MSM-2DEG varactor properties, including current–voltage (I–V), capacitance–voltage (C–V), and frequency response of the proposed Surge Protection circuit, are presented. To verify its capability of Surge Protection, we replace the metal oxide varistor (MOV) and resistor (R) in a state-of-the-art Surge Protection circuit with the sulfur-treated MSM-2DEG varactor under the application conditions of system-level Surge tests. The measured results show that the proposed Surge Protection circuit, consisted of a gas discharge arrester (GDA) and a sulfur-treated MSM-2DEG varactor, can suppress an electromagnetic pulse (EMP) voltage of 4000 to 360 V, a reduction of 91%, whereas suppression is to 1780 V, a reduction of 55%, when using only a GDA.
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Improvement of Surge Protection by Using an AlGaN/GaN-Based Metal-Semiconductor-Metal Two-Dimensional Electron Gas Varactor
Japanese Journal of Applied Physics, 2012Co-Authors: Yi-cherng Ferng, Liann-be Chang, Chun-yu Cheng, Ping-yu Kuei, Lee ChowAbstract:In this paper, a varactor with metal–semiconductor–metal diodes on top of the (NH4)2S/P2S5-treated AlGaN/GaN two-dimensional electron gas epitaxial structure (MSM-2DEG) is proposed to the Surge Protection for the first time. The sulfur-treated MSM-2DEG varactor properties, including current–voltage (I–V), capacitance–voltage (C–V), and frequency response of the proposed Surge Protection circuit, are presented. To verify its capability of Surge Protection, we replace the metal oxide varistor (MOV) and resistor (R) in a state-of-the-art Surge Protection circuit with the sulfur-treated MSM-2DEG varactor under the application conditions of system-level Surge tests. The measured results show that the proposed Surge Protection circuit, consisted of a gas discharge arrester (GDA) and a sulfur-treated MSM-2DEG varactor, can suppress an electromagnetic pulse (EMP) voltage of 4000 to 360 V, a reduction of 91%, whereas suppression is to 1780 V, a reduction of 55%, when using only a GDA.
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On chip Surge Protection for GaN-power LEDs by ZnO thin film varistor
Gallium Nitride Materials and Devices III, 2008Co-Authors: Liann-be Chang, Yuan-hsiao Chang, Yuan-shun Chang, Ming-jer JengAbstract:High ESD endurance capability is an important issue for the extensive application of power light emitting diodes (LEDs). Conventional ceramic varistor based on sintered bulk zinc oxide (ZnO) with various metal oxides as additives have widely used in Surge Protection device by grounding the excessive current for a long time. Those sintered bulk ZnO devices are known to exhibit high nonlinearity coefficient (α>50) and good reliability for many commercial applications. However, sintering manufacture method limits the practicability of integrating bulk ZnO varistor with other semiconductor devices. In this research, we report on the thin-film ZnO produced by sputtering system and post-heat treatment which have shown good varistor characteristics. The nonlinear coefficients (α) in the correspondent current -voltage (I-V) curve can up to 50 at a high electric field of 1.1 kV/cm, and, with efficiently resolving thermal generated by high injected current, this thin film varistor can conduct current to the density as high as 20A/cm 2 successfully. In addition, our thin film varistor devices combined with power LEDs by gold wires bonding revealed an improved electrostatic discharge (ESD) ability of up to 400V apparently. This wire bonding configuration will be modified to a flip-chip LED with the ZnO/Si submount in the future. Sputtering and annealing are two commonly used processes in general semiconductor manufacture procedures which are adopted in our ZnO thin film deposition. Therefore, our proposed method have provided a new possible solution to integrate not only LEDs but also other semiconductor devices with thin film varistor owning Surge Protection capability, especially to accomplish an on-chip Surge Protection.