About: Circuit breaker is a research topic. Over the lifetime, 47182 publications have been published within this topic receiving 231295 citations. The topic is also known as: breaker & electrical breaker.
Papers published on a yearly basis
TL;DR: In this paper, the authors propose a handshaking method to locate and isolate the faulted dc line and restore the MTDC without telecommunication, which is shown to be more economical than the dc circuit breakers.
Abstract: A VSC-MTDC (multi-terminal dc) system consists of voltage-source converters (VSCs) connected to a dc network at their dc terminals. The MTDC is most vulnerable to a dc fault which paralyses all the VSCs until the dc fault is cleared. As dc circuit breakers are expensive, this paper proposes a solution based on extinguishing the dc fault current by opening all the ac-circuit breakers (ac-CBs) which the VSCs are already equipped with on the ac-sides. However, it is necessary to identify which dc line is the faulted line (in case it is a permanent fault) so that it can be isolated by fast dc switches (which are much more economical than the dc circuit breakers), prior to restoring the MTDC system by re-closing all the ac-CBs. This paper presents the handshaking method, which locates and isolates the faulted dc line and restores the MTDC without telecommunication.
TL;DR: In this paper, the authors summarize the state of knowledge of the effects of power system harmonics on equipment, including thermal overloading, disruption, and dielectric stressing, and quantitatively describe the effects.
Abstract: The authors summarize the state of knowledge of the effects of power system harmonics on equipment. The general mechanisms presented are thermal overloading, disruption, and dielectric stressing. Quantitative effects are presented or referenced whenever possible. However, many of the effects are can only be qualitatively described. The types of equipment considered are adjustable speed drives, capacitors, circuit breakers, fuses, conductors, electronic equipment, lighting, metering, protective relays, rotating machines, telephones, and transformers. >
TL;DR: In this paper, the effect of the dynamic voltage restorer (DVR) on a distribution test facility in Kyndby, Denmark is investigated under both faulted and non-faulted system states, for a variety of linear and nonlinear loads.
Abstract: The dynamic voltage restorer (DVR) has become popular as a cost effective solution for the protection of sensitive loads from voltage sags. Implementations of the DVR have been proposed at both a low voltage (LV) level, as well as a medium voltage (MV) level; and give an opportunity to protect high power sensitive loads from voltage sags. This paper reports practical test results obtained on a medium voltage (10 kV) level using a DVR at a distribution test facility in Kyndby, Denmark. The DVR was designed to protect a 400-kVA load from a 0.5-p.u. maximum voltage sag. The reported DVR verifies the use of a combined feed-forward and feed-back technique of the controller and it obtains both good transient and steady-state responses. The effect of the DVR on the system is experimentally investigated under both faulted and nonfaulted system states, for a variety of linear and nonlinear loads. Variable duration voltage sags were created using a controllable LV breaker fed by a 630 kVA distribution transformer placed upstream of the sensitive load. The fault currents in excess of 12 kA were designed and created to obtain the required voltage sags. It is concluded the DVR works well in all operating conditions.
TL;DR: In this article, an earthed bipole HVDC grid was modeled in PSCAD, and using simulation results, the necessity of di/dt limiting inductors to contain the rise of fault currents within the capacity of current hybrid dc breakers was demonstrated.
Abstract: Different HVDC grid types and the respective protection options are discussed. An earthed bipole HVDC grid was modeled in PSCAD, and using simulation results, the necessity of di/dt limiting inductors to contain the rise of fault currents within the capacity of current hybrid dc breakers is demonstrated. The impact of different inductor sizes on current rise was studied. A fault detection and localization scheme using the rate of change of voltage measured at the line side of the di/dt limiting reactors is proposed. The protection system was modeled and tested under different fault types and locations. The results show that the proposed method of HVDC grid protection is feasible using the current hybrid dc breaker technology. A systematic procedure for setting the necessary protection threshold values is also demonstrated.
TL;DR: Breaker type, for waves on smooth concrete slopes, depends on beach slope m, wave period T, and either deep-water or breaker height, H 0 or Hb as discussed by the authors.
Abstract: Breaker type, for waves on smooth concrete slopes, depends on beach slope m, wave period T, and either deep-water or breaker height, H0 or Hb. For forty-three varied laboratory conditions, breaker type can be sorted fairly well by either of two dimensionless combinations of these variables, an offshore parameter, H0/(L0m2) or an inshore parameter, Hb/(gmT2). As either of these parameters increases, breaker type changes from surging or collapsing to plunging to spilling. For the offshore and inshore parameters, respectively, the surge-plunge transition values are about 0.09 and 0.003 and the plunge-spill transition values are about 4.8 and 0.068. The deep-water heights in the offshore parameter were computed from linear, wave-generator theory. Breaker type data were obtained from films of breaking waves for conditions that produced a dominant breaker type, free from interference by secondary waves.
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