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Effect of Circuit Breaker Shunt Resistance on Chaotic Ferroresonance in Voltage Transformer
Advances in Electrical and Computer Engineering , 2010, DOI: 10.4316/aece.2010.03012
Abstract: Ferroresonance or nonlinear resonance is a complex electrical phenomenon, which may cause over voltages and over currents in the electrical power system which endangers the system reliability and continuous safe operating. This paper studies the effect of circuit breaker shunt resistance on the control of chaotic ferroresonance in a voltage transformer. It is expected that this resistance generally can cause ferroresonance dropout. For confirmation this aspect Simulation has been done on a one phase voltage transformer rated 100VA, 275kV. The magnetization characteristic of the transformer is modeled by a single-value two-term polynomial with q=7. The simulation results reveal that considering the shunt resistance on the circuit breaker, exhibits a great mitigating effect on ferroresonance over voltages. Significant effect on the onset of chaos, the range of parameter values that may lead to chaos along with ferroresonance voltages has been obtained and presented.
Improving Transient Recovery voltage of circuit breaker using Fault Current Limiter  [cached]
Amir Heidary,Hamid Radmanesh,Seyed Hamid Fathi,Hamid Reza Rajabi Khamse
Research Journal of Applied Sciences, Engineering and Technology , 2012,
Abstract: This study investigates influence of Fault Current Limiter (FCL) on short-circuits current level of substation bus bar splitter circuit breaker and its TRV. An approach for TRV evaluation is developed and applied for proposed power system as shown in this study. FCL circuit is connected to the power system in order to limit TRV. The limiter circuit consists of two equal windings which are turned around unique magnetic core. One of the windings is connected in series with the power system network and the other is connected to the network via series capacitor and power electronic switches. During normal operating condition, both tyristors are in on state and current of the primary and secondary windings are equal. This causes zero impedance of the limiter. During fault, faults current cause the power electronic switch to turn off which increases the limiter impedance. By increasing the limiter impedance, amplitude of TRV decreases substantially. The novel method presented in this study is a cheap and successful scheme.
Influence of dc Component during Inadvertent Operation of the High Voltage Generator Circuit Breaker during Mis-Synchronization  [PDF]
Kadri Kadriu, Ali Gashi, Ibrahim Gashi, Ali Hamiti, Gazmend Kabashi
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.53022

This paper analyses the synchronization problem of a generator onto power system without satisfying synchronization condition. The main focus of the paper is on the impact of the dc component of the current in the high voltage circuit breaker during its close-open operating cycle. Using real time measurements of currents/voltages and angles during the close-opening cycle of high voltage generator circuit breaker and the impact of the dc component of current in context of interrupting large magnitude of current from the circuit breaker. In addition, the paper describes a study case model and the results of simulations performed using the software EMTP-ATP of an actual incident that occurred during the inadvertent synchronization of a large 339 MW, 24 kV generator to the grid.

Simulation Model of Shipboard Low Voltage Molded Case Circuit Breaker Based on PSCAD/EMTDC  [PDF]
Jing Huang, Bing Shen, Feng Yang
Journal of Power and Energy Engineering (JPEE) , 2014, DOI: 10.4236/jpee.2014.24072
Abstract: A simulation model of shipboard low voltage molded case circuit breaker (MCCB) is developed based on power system simulation software PSCAD/EMTDC. The motion characteristic of the magnetic instantaneous acting trip based on electromagnetic characteristic analysis and Cassie arc model are applied into the simulation model to describe the dynamic behavior of the MCCB
during short-circuit protection. The results of short-circuit interruption experiments verify the simulation model. It demonstrates that the simulation model has good prospect in optimizing the design and protection performance of MCCB.
Analysis and Calculation of the Screw Spring Contact for High-voltage Circuit Breaker

- , 2016,
Abstract: 触指是高压断路器最核心的部件,计算其接触压力、分析滑动摩擦力的变化是研究断路器机构动态特性的关键。以螺旋弹簧触指的结构特点为基础,列出弹簧触指标准化尺寸。将一个节距的弹簧触指简化为一端固定的当量悬臂梁,建立了触指径向变形量和接触压力的变化方程,运用辛普森数值积分法进行计算,考虑不同型号触指参数对额定圈数的影响,得到触指滑动摩擦力的变化规律。
Contact is the core of the high-voltage circuit breaker, calculations of the contact pressure and analysis of the sliding friction change are the key points for the study of dynamic characteristics of high-voltage circuit breaker mechanism. In this paper, standardized dimensions of spring contact were listed based on structural features of screw spring contact. On the basis that one pitch of spring was considered as an equivalent cantilever, governing equations of radial deformation and pressure of spring contact were established and calculated by using Simpson numerical integration method. the changing rule of sliding friction was received by considering the effects of different type contact parameters on the rated laps of contact at the same time
Application of BJT as a bidirectional switch for low voltage circuit protection  [PDF]
G. R. Padmini,M. Satyam,K. Lalkishore,P. A. Govindacharyulu
Journal of Engineering and Applied Sciences , 2010,
Abstract: In this paper the function of an all electronic circuit breaker has been demonstrated. Till recently the alternatives to electromechanical and magnetic circuit breakers are very few. Solid state devices are reliable and have high life time. This circuit breaker is demonstrated with BJT as a bidirectional switch. The operation of the bidirectional switch is analyzed for different operating conditions to determine the limitations of this design. Bidirectional switches with TRIAC, IGBT are commercially available however circuit breaker with BJT as a bidirectional switch is a new approach for low voltage circuit protection.
Approaching the Processes in the Generator Circuit Breaker at Disconnection through Sustainability Concepts  [PDF]
Cornelia A. Bulucea,Marc A. Rosen,Doru A. Nicola,Nikos E. Mastorakis,Carmen A. Bulucea
Sustainability , 2013, DOI: 10.3390/su5031161
Abstract: Nowadays, the electric connection circuits of power plants (based on fossil fuels as well as renewable sources) entail generator circuit-breakers (GCBs) at the generator terminals, since the presence of that electric equipment offers many advantages related to the sustainability of a power plant. In an alternating current (a.c.) circuit the interruption of a short circuit is performed by the circuit-breaker at the natural passing through zero of the short-circuit current. During the current interruption, an electric arc is generated between the opened contacts of the circuit-breaker. This arc must be cooled and extinguished in a controlled way. Since the synchronous generator stator can flow via highly asymmetrical short-circuit currents, the phenomena which occur in the case of short-circuit currents interruption determine the main stresses of the generator circuit-breaker; the current interruption requirements of a GCB are significantly higher than for the distribution network circuit breakers. For shedding light on the proper moment when the generator circuit-breaker must operate, using the space phasor of the short-circuit currents, the time expression to the first zero passing of the short-circuit current is determined. Here, the manner is investigated in which various factors influence the delay of the zero passing of the short-circuit current. It is shown that the delay time is influenced by the synchronous machine parameters and by the load conditions which precede the short-circuit. Numerical simulations were conducted of the asymmetrical currents in the case of the sudden three-phase short circuit at the terminals of synchronous generators. Further in this study it is emphasized that although the phenomena produced in the electric arc at the terminals of the circuit-breaker are complicated and not completely explained, the concept of exergy is useful in understanding the physical phenomena. The article points out that just after the short-circuit current interruption by the generator the circuit-breaker (when the GCB has been subjected at the metal contact terminals to the high temperature of a plasma arc, up to 50,000 K) between its opened contacts, there arises the transient recovery voltage (TRV) which constitutes the most important dielectric stress after the electric arc extinction. Since the magnitude and shape of the TRV occurring across the generator circuit-breaker are critical parameters in the recovering gap after the current zero, in this paper, we model, for the case of the faults fed by the main step-up transformer, the
利用开断模型分析引弧板对低压断路器 电弧运动的影响
Influence of Different Arc Run??on End Tab on the Arc Movement Process of Low Voltage Circuit Breaker with Interruption Model

- , 2016, DOI: 10.7652/xjtuxb201610005
Abstract: 为了描述电弧在跑弧道上运动的动态过程,得出引弧板对低压断路器灭弧性能的影响规律,提出了一种基于开断模型的描述电弧在跑弧道(含引弧板)上运动全过程的分析方法。首先建立了一种基于多场耦合的对低压断路器开断过程进行仿真的方法,该方法通过对多体动力学仿真软件ADAMS进行二次开发,实现了开断过程中电路、电弧、气吹、电动斥力、复杂机械运动等多场域的相互耦合;然后以某带引弧板的低压断路器为分析对象,利用所提出的仿真方法,对电弧从起燃、运动、转移到熄灭的全过程进行了计算仿真,分析了不同引弧板形状对低压断路器开断性能的影响,并通过实验验证。计算与实验结果表明,钩状引弧板的弧形轮廓在迎着电弧运动方向上具有更大的接触面积,且弧角朝栅片方向弯曲符合电弧的整体运动趋势,有利于电弧在弧根转移后进一步进入灭弧栅片,从而减少触头的烧蚀和提升电弧进入栅片的效果。
To describe the dynamic process of electric arc on the arc run??on plate to yield the influencing law of the arc run??on end tab on the breaker interruption performance, an analysis strategy based on the interruption model of low voltage circuit breaker is proposed for arc movement on the arc runner with arc run??on end tab. Firstly, a multi??field coupled calculation model that enables to simulate the interruption process of low voltage circuit breaker is constructed. Secondly developing the multi??body dynamic simulation software ADAMS, a set of differential equations describing the coupling relations among electric circuit, magnetic field, puffer effect, complex mechanical movement and dynamic arc model are established. This model is used to simulate the arc movement process undergoing arc striking, moving, transferring and extinguishing. The influences of different structures of arc run??on end tabs on the interruption performance of low voltage circuit breaker are analyzed and verified by the tests. Both calculation and experiment results demonstrate that the hook??like arc run??on end tab has a larger contact area than the flat end tab towards the arc movement direction, that the arc angle of the hook??like end tab bends to the direction of splitter plates conforming to the overall movement trend of the electric arc, and the arc root on hook??like end tab is thus easier to jump onto the arc run??on plate than on the flat end tab to consequently decrease the contact erosion
Design and Implementation of an Intelligence Circuit Breaker Communication Module Based on Modbus Protocol
基于Modbus 协议的智能断路器通信模块设计与实现

LUO Yi-Feng,DAI Yu-Xing,LI Peng,WANG Wei-Guo,

计算机系统应用 , 2010,
Abstract: The design of Communication Module for intelligent circuit breaker based on the Modbus protocol is introduced according to the technical demands of intelligent low voltage circuit breaker with communication capability.The form of networking and mechanisms of Modbus communication,as well as Modbus protocol stack software implementation are expounded.The power circuit and RS485 interface circuit are also presented.The module is effective to achieve the centralized monitoring and long-distance communications.
Ramandeep Singh,Baljinder Singh
International Journal of Computers & Technology , 2013,
Abstract: The purpose of this paper is to examine the significant developments in MV and LV switchgear technology over the last few decades and why they are only recently beginning to benefit the users. A recent development now has sufficient field experience to show how through innovative design it has been possible to vastly improve an auto-reclosing circuit breaker. The author believes that the same innovative ideas will soon be applied to all types of switchgear. The next generation of military switchgear is likely to be developed for the Electric Warship. Irrespective of which distribution supply is used the next generation of switchgear should benefit from the new technology. Calibration of Miniature Circuit Breaker takes a lot of time. Calibration is done to satisfy the International Standards so that all the MCBs are standardized. In this paper we concerned with decreasing this calibration time of MCBs whose rated current is less than or equal to 32 Amps. Calibration can be done by two methods, wiz, and Dual current and single current parameter method. This paper also deals with the decrease in the Calibration time and increase in Production efficiency by the use of later method which is a modification of the former one proposed and implemented here. This is done by employing faster motor for the calibration. A recent development now has sufficient field experience to show how through innovative design it has been possible to vastly improve an auto-reclosing circuit breaker. The author believes that the same innovative ideas will soon be applied to all types of switchgear.
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