Type Of Breaker Research Articles

The influence of toe geometry on toe armour stability for conventional rubble mound breakwaters

Rubble mound breakwaters have toe structures that provide support to the armour layer and prevent damage to the structure from scouring. In this way, toe failure may be regarded as one of the primary failure modes of rubble mound breakwaters. Several formulae have been proposed for toe stability with conflicting results owing to the neglect of factors such as storm duration and armour layer slope. In the present study, a statically stable rubble mound with rock armoured toe was tested under irregular waves. The effects of wave height, wave period, armour layer slope, water height in front of the structure, water height above the toe, and toe width on the hydraulic stability of a toe structure are investigated. Toe width was found to be ineffective on toe stability, while the relative depth was found as an effective parameter for the toe stability. Greater toe damage was observed by increasing wave height and storm duration. The results highlighted the necessity for a new stability number involving the type of wave breaker on the armour slope with a critical Iribarren value of 4.1. Based on the data from the present study and the findings of another study, new formulae have been developed for estimating toe damage in rubble mound breakwaters. Evaluating the proposed formula using other researchers’ data and formulae highlighted its strengths.

Design and research of a new type of electromagnetic vacuum circuit breaker

Design and research of a new type of electromagnetic vacuum circuit breaker

Study on the influence of mechanism dispersion on transient recovery voltage distribution of modular DC vacuum circuit breakers

AbstractA simulation analysis and an experiment are carried out to investigate how the gap difference between the breaks of a direct current vacuum circuit breakers with multi‐breaks (MB‐DC VCB) caused by the mechanism dispersion of the breaker influences the distribution of TRV among the breaks. An interruption model of MB‐DC VCB, combining the continuous transition model, is established to analyse the rising rate of transient recovery voltage and the dielectric strength recovery speed of the breaks for MB‐DC VCB under different gap difference conditions. Based on the experimental platform of dual break DC vacuum circuit breaker breaking, the correctness of the simulation model is verified on a DC VCB with the double‐breaks interruption experimental platform. Moreover, a model is applied to the non‐synchronous interruption simulation of a DC VCB with three‐breaks. The relationship between the TRVs of the breaks under different gap difference conditions is analysed using the comparative analysis method, obtaining the maximum gap difference at the moment of breaking failure. The results of this study show that large‐gap breaks have a higher TRV than small‐gap breaks (the fracture of the action delay module), with double fractures reaching 1.4 times and triple fractures reaching a maximum of 1.52 times; the ability of small‐gap breaks to withstand TRV is weak, giving rise to re‐breakdown or even interruption failure; as the number of fractures increases, the maximum gap difference also increases. Improving the synchronous interruption ability of the MB‐DC VCB is conducive to improving the interruption performance and interruption success rate of this type of a circuit breaker.

The energy dissipation topology and characteristics of GaInSn liquid metal and ZnO resistors based on high-voltage DC circuit breakers

High voltage direct current (HVDC) circuit breakers play a very crucial role in HVDC transmission systems. Energy dissipation circuit branches are the main part of the HVDC breaker. The volume and size of energy dissipation branches are the bottlenecks of the HVDC breaker, and the existing energy dissipation schemes can not meet the lightweight requirements. In this work, a combined energy dissipation scheme based on gallium indium tin (GaInSn) liquid metal and ZnO resistors is proposed for the energy dissipation branch of a circuit breaker. Firstly, the self-shrinking of GaInSn liquid metal mechanism is analyzed and the energy dissipation characteristics at different stages are investigated. The variation patterns of short circuit current, arc voltage, resistance and other parameters in the process of liquid metal arcing and energy dissipation are obtained. Secondly, the circuit model of liquid metal in arcing and energy dissipation process is established. The equivalent nonlinear time-varying conductance of the arcing process of the liquid metal dissipative element is simulated by combining the volt-ampere characteristic curves of the liquid metal dissipative module. Finally, the topology of energy dissipation circuit branches combined by GaInSn liquid metal and ZnO resistors is proposed. At the same time, the HVDC breaker model combined by a hybrid DC circuit breaker and energy dissipation circuit branches is constructed. The energy dissipation ratio and distribution law of GaInSn liquid metal and ZnO resistors in the composite type of circuit breaker are verified. The composite dissipation improves the overall energy dissipation density of the circuit breaker compared to the conventional ZnO resistors energy dissipation.

Investigation on the fault monitoring of high-voltage circuit breaker using improved deep learning.

Mechanical faults are the main causes of abnormal opening, refusal operation, or malfunction of high-voltage circuit breakers. Accurately assessing the operational condition of high-voltage circuit breakers and delivering fault evaluations is essential for the power grid's safety and reliability. This article develops a circuit breaker fault monitoring device, which diagnoses the mechanical faults of the circuit breaker by monitoring the vibration information data. At the same time, the article adopts an improved deep learning method to train vibration information of high-voltage circuit breakers, and based on this, a systematic research method is employed to identify circuit breaker faults. Firstly, vibration information data of high-voltage circuit breakers is obtained through monitoring devices, this vibration data is then trained using deep learning methods to extract features corresponding to various fault types. Secondly, using the extracted features, circuit breaker faults are classified and recognized with a systematic analysis of the progression traits across various fault categories. Finally, the circuit breaker's fault type is ascertained by comparing the test set's characteristics with those of the training set, using the vibration data. The experimental results show that for the same type of circuit breaker, the accuracy of this method is over 95%, providing a more efficient, intuitive, and practical method for online diagnosis and fault warning of high-voltage circuit breakers.

Sistem Switching pada Automactic Transfer Switch (ATS) menggunakan Arduino UNO

Panel is a form of alternative energy that is widely used by humans today to be managed into electrical energy. Solar panels are made of semiconductor materials, especially silicon which is coated by a special additive. When sunlight approaches the cell, the electrons will be released from the silicon atoms and flow to form an electrical circuit so that electrical energy can be generated. The results of the study, where the transfer or switching carried out by the relay was orderead by the coding of the arduino uno. At the time before the transfer of switching, the arduino uno will delay a few seconds before switching the source. Where this ATS perfomance is controlled throught a magnetic force from an oen condition to a closed condition. As abreaker and a power connector, this tool has a material in the from of connecting contact point has a large size so that it can distribute large power loads. Then the contact point has a large size so that it can distribute large electric currents, one example of a type of breaker and connector ia an AC and DC relay as an automatic regulating device. From the results of the analysis it is concluded that the Switching Automatic Transfer Switch work process can be carried out by the relay on the order of the coding from Arduino UNO automatically

High-Performance and Economical Forced Resonant DC Circuit Breaker: Topology, Design, and Development

A dc circuit breaker (DCCB), which can interrupt a fault current, is the key equipment in a voltage source converter-based high-voltage dc (VSC-HVDC) transmission system. However, the existing DCCBs cannot balance economy and high reliability, thus preventing their large-scale application. This article proposes a new type of forced resonant mechanical circuit breaker (FR-MCB) that can generate an unlimited number of zero crossings to meet the requirements of low cost and high performance. To improve the performance of interrupting a fault current, a control strategy is proposed to offset the adverse effects of the delay in switching the insulated-gate bipolar transistor (IGBT) on and off. Moreover, the parameter optimization method is studied to further reduce the cost of the FR-MCB. Finally, an 80-kV/10-kA prototype with high reliability and a much lower cost than those of the existing hybrid circuit breaker (HCB) and MCB schemes is developed, providing a new technical route for improving the economy of dc fault protection.

Numerical Simulations of Waves Breaking over a Rectangular Submerged Reef Consisting of a Double Step: Analogies with massive Natural Wave Breaking over Abrupt Bathymetries

The aim of this article is not to study any practical design for a breakwater device nor to show the evidence of a particular event when waves break over a varying bathymetry, but to promote a paper showing an interesting idea of wave decomposition prior to impact, used in an experimental and numerical study published by Yasuda et al. (Proceedings 25th international conferences coastal engineering, pp 300–313, 1996) and Yasuda et al. (Coast Eng J 41(2): 269–280, 1999. We investigated the new type of breaker, proposed by Yasuda et al. (1996), by detailing several geometric aspects which lead to the unusual size and behavior of some very large plunging jets generated when waves break above some drastic changes of bathymetry. We thoroughly investigated all geometrical aspects of the breaking process, to propose a classification of the breaker types which were observed in our numerical results. We indicated the influences of the reef parameters (steps heights and lengths) on the subsequent breaking process. We also showed that the air entrainment was indeed much larger during the composite breaker occurrence.

Mechanical Fault Diagnosis of High Voltage Circuit Breaker based on Improved GSO-SVM Algorithm

The vibration signal generated by the transmission and impact of mechanical components of circuit breaker has chaotic performances, which is difficult to be analysed by conventional signal processing methods. The phase space reconstruction of vibration signal is worked on, and the signal reconstruction parameters are calculated by mutual information method and Cao algorithm respectively. The vibration signal is reconstructed into a high-dimensional space, and its permutation entropy is calculated as a feature vector. Support vector machine (SVM) is used to identify the failure type of circuit breaker, and PSO improved GSA hybrid algorithm is used to optimize the parameters of SVM so as to obtain high recognition accuracy. The experiment is carried out with the measured vibration signal of the typical operation state of the circuit breaker. The results show that the characteristics of circuit breaker vibration signals can be extracted accurately with the combination of phase space reconstruction and permutation entropy. By using PSO-GSA-SVM, the fault types of circuit breakers can be identified quickly and effectively, and the problems of path distortion, energy leakage and mode overlap of existing diagnosis methods can be solved.

Analysis of Suspended Potential Discharge Defects by SF6 Decomposition Products

The type and content of SF6 decomposition products are directly related to the type, location and degree of fault. Based on the analysis of the abnormal SF6 gas decomposition product content and discharge type of 126kV Porcelain Column type circuit breaker, the potential fault of the circuit breaker is judged to be suspension potential discharge fault. After disassembling the circuit breaker, it is found that the abnormal phase of the insulation rod is deformed, the pin become thin, and there are solid decomposition products, the sulfides and fluoride, which are mainly composed of iron, aluminum, chromium and manganese, further confirm that the potential fault of the circuit breaker is suspension potential discharge fault. The forming process and reaction mechanism of the suspended potential discharge fault are analyzed. Once the fault occurs, its function will promote the development of the fault. The influence of the suspension potential discharge fault on the performance of the circuit breaker is also analyzed. When the suspension potential discharge fault exists, it will cause the abnormality and even affect the normal operation of the circuit breake.

Effect of The Shape of Balloon Breaker on Yarn Tension during Unwinding from COPS Part ( I).(Dept.T)

In this work the yarn tension was measured during withdrawing the yarn from stationary cops. The value of yarn tension was measured under the effect of the following parameters: - Distance between cops and yarn guide (without using balloon breaker) - Type of balloon breaker - Linear density of yarn The value of yarn tension during direct unwinding from cops can be reduced by varying the distance between cops and yarns guide. It was found that the small distance between cops and yarn guide is suitable, since the level of yarn tension is low. In case of using balloon breaker the value of yarn tension can be reduced by using a balloon breaker with triangular cross section.

Effect of The Dimensions of Balloon Breaker with Triangular Cross Section on Yarn Tension(Part II) (Dept.T)

In this work the yarn tension was measured during withdrawing the yarn from stationary cops. The value of yarn tension was measured under the effect of the following parameters: - Distance between cops and yarn guide (without using balloon breaker) - Type of balloon breaker - Linear density of yarn The value of yarn tension during direct unwinding from cops can be reduced by varying the distance between cops and yarns guide. It was found that the small distance between cops and yarn guide is suitable, since the level of yarn tension is low. In case of using balloon breaker the value of yarn tension can be reduced by using a balloon breaker with triangular cross section.

Evaluation of triethanolamine-cashew nutshell liquid derivatives as crude oil emulsion breakers

Three bio-based crude oil emulsion breakers have been prepared from agricultural waste by chemical treatment of cashew nutshell liquid (CNSL) extract with triethanolamine via a one-pot reaction at 120 ℃. The triethanolamine-ester derivatives were characterized by Fourier Transform–InfraRed spectroscopy. Their effectiveness as crude oil emulsion breakers were investigated experimentally using the bottle test method. The effect of solvent type, water content, and concentration of the emulsion breaker, was used to study the demulsification process and determine their demulsification efficiency at a temperature of 60 ℃ for a contact time of 180 min. A commercial demulsifier, PhaseTreat 4633 (PT-4633) was used as a benchmark. Performance evaluation of the prepared emulsion breakers revealed their effectiveness in descending order as: triethanolamine dianacardate (TED) > triethanolamine trianacardate (TET) > triethanolamine anacardate (TEA). The data reveals that their emulsion breaking efficiency increases with increasing emulsion water content, and concentration. PT-4633 exhibited better demulsification efficiency than the triethanolamine-esters in xylene across the concentration and water content studied. Improved water separation was however observed for the triethanolamine-esters in butanol, as triethanolamine trianacardate (TET) performed better than PT-4633 at 10 ppm to 20 ppm at 30% water content with a water separation of 83.33% and 80% respectively. The evaluated triethanolamine ester derivatives exhibited better emulsion breaking potentials in butanol than xylene at shorter times, which may be due to the synergistic effect of butanol. Therefore, butanol could be used as a sustainable solvent substitute for xylene in demulsifier formulations.

PERFORMANCE PREDICTION OF HYDRAULIC BREAKERS IN EXCAVATION OF A ROCK MASS

The demand for the usage of hydraulic rock breakers in excavating rock masses has increased recently for environmental and economic reasons. The conventional method (i.e., drill and blasting technique) has many restrictions due to environmental aspects. In this paper, we propose a methodology for the prediction of the performance of hydraulic rock breakers in the excavation of a rock mass. The case study area is located in Northwest Egypt on the shoreline of the Mediterranean Sea. Extensive site investigation was implemented using exploration boreholes showing that the majority of the site is limestone with lenses of sands. Based on the collected rock properties, mapping of both the rock quality (RQD) and the uniaxial compressive strength (UCS) for the rock mass was conducted. Such mapping of the mechanical properties helps in the zoning of a rock mass and grouping the similar rock zones of nearly matched properties. Due to economic and machinery availability concerns, this study focuses on very small, small, and medium capacity hydraulic breakers. For each type of rock breaker, calculations of the net breaking rate (NBR) are implemented for each group of the rock with similar properties. The challenge of this methodology is that the excavation of the rock mass shall be implemented in a very limited time frame (only one year ≈ 300 workdays). Therefore, two scenarios of light-duty and medium rock breakers are applied providing the number of machines required with specifications and working days. The first scenario is assigned to medium duty machines, while the second scenario concerns very small to small rock breakers. In general, such a sequence could be adopted for other cases with different rock mass properties, hydraulic breakers specifications and any desired time frame.

Operation Characteristics for the Superconducting Arc-Induction Type DC Circuit Breaker

The multi-terminal direct current network is expected to commercialize while carrying out projects related to DC power systems worldwide. Accordingly, it is necessary to develop a DC circuit breaker required for the DC power system. A DC circuit breaker should be developed to protect the DC power system and the consumer from the transient state on the line in any case. Currently, the use of power semiconductors increases the performance of DC circuit breakers. However, power semiconductors are expensive and suffer series of losses from frequent failures. Therefore, the DC circuit breaker must have a reliable, stable, and inexpensive structure. We proposed a new type of arc-induction type DC circuit breaker. It consists of a mechanical blocking contact, an induction needle and a superconducting magnet. It blows the arc with an induction needle using the Lorentz force according to the high magnetic field of the superconducting magnet. The arc-induction needle absorbs the arc and flows through the ground wire to the ground to extinguish the arc. We established this principle of arc induction as a mathematical model. In addition, the Maxwell program was used to secure data of electric and magnetic fields and apply them to mathematical models. The results obtained through numerical analysis were analyzed and compared. As a result, we confirmed that the magnitude of the force exerted on the electrons between the mechanical contacts with the superconducting magnets increased about 1.41 times and reasoned the arc-induction phenomenon out numerically.

Wave Breaker Types on a Smooth and Impermeable 1:10 Slope

This research identified the types of wave breaker on a non-overtoppable, smooth and impermeable 1:10 slope under regular waves. Experimental tests were carried out in the Atmosphere-Ocean Interaction Flume of the Andalusian Institute for Earth System Research (University of Granada). Using the experimental space [log(h/L)–log(H/L)] and the alternate slope similarity parameter [χ = log (h/L H/L)], a complete set of breaker types was identified. Four types of wave breaker were then added to Galvin’s classification. Our results showed that the value of the Iribarren number was not sufficient to predict the expected type of wave breaker on the slope. Except for spilling and early plunging breakers, no biunivocal relationship was found between Ir and the type of breaker. The data obtained in the physical model were further enriched with the results of the flow characteristics and the wave energy transformation coefficients obtained with the IH-2VOF numerical model on a 1:10 impermeable slope. This research study, presented in this paper, showed that the Iribarren number is not a convenient wave breaking similarity parameter.

Development of Fast Acting Electronic Circuit Breaker

The rapid increase in population has more demand and consumption of electrical energy in the market, use of equipments such as electrical and electronic components are also costlier. In order to protect the system from overload, or short circuit here is one possibility, which is by fast acting electronic circuit breaker. A circuit breaker is an automatically operating switch designed to shut down the power supply when it is overloaded. The tripping depends on the current passing through the CT’s which is connected in series with load. The project is designed to develop the power supply which shuts down when it is overloaded by using a fast acting electronic circuit breaker. The concept of developing a electronic circuit breaker came into focus realizing that the conventional circuit breakers such as MCB’s and fuse take longer time to trip. Therefore for sensitive loads it is very important to activate the tripping mechanism within short period of time. We know that the Modern technologies are paramount to provide operational reliability and financial profitability, so it is very important to develop an electronic circuit breaker by using a micro controller arduino. Here an electronic circuit breaker is designed using arduino in which program is dumped and a particular is set so that the system can shut down when it is overloaded. Here the voltage is sensed and rectified to DC and then it is compared with a preset voltage by a level comparator to generate an output that drives a relay to trip the load. The relay is preferred in place of semiconductors because such solid state switches would invariably fail in case of accidental short circuits. This project is designed to overcome the drawback of thermal type of circuit breaker like MCB based on a thermal bimetal lever trip mechanism which is very slow. This project is based on the current sensing across a series element typically a CT (Current Transformer). The current sensed which is compared against the preset value proportional to the voltage by comparator which is inbuilt in arduino to generate an output that drives a relay to trip the load very fast.

2D water-wave interaction with permeable and impermeable slopes: Dimensional analysis and experimental overview

The main objective of this research is to characterize and quantify the prevalent physical processes in the energy transformation of a regular wave train when it interacts with permeable and impermeable breakwaters. Two sources of experimental data are considered: (a) numerical experiments on an undefined impermeable rigid slope, using the numerical model (IH–2VOF), and (b) physical experiments on a non-overtoppable permeable breakwater with a cube armor layer and a porous core of finite width in a 2D wave flume. A revised dimensional analysis reveals that the relative water depth, h/L, and the incident wave steepness, H/L, at the toe of permeable and impermeable breakwaters are the key factors to define and optimize the experimental space (HI/L, h/L). Moreover, the product of (h/L) (HI/L) can be applied to identify the type of wave breaking and the domains of wave energy transformation, and to quantify the reflected and transmitted energy coefficients and the dissipation rate (KR2,KT2,D∗). Fitting an experimental curve (i.e. a sigmoid function) to the impermeable data, the slope is a plotting parameter. The same conclusion is obtained for a permeable breakwater; in addition the wave energy coefficients depend on the relative breakwater width B*/L, and the relative core grain size and D50,p/L, and armor unit diameter, Da/L. Because the range of the design factors spans several orders of magnitude, a log-transformation provides a well behaved experimental space [ln(h/L), ln(H/L)] which is likely of benefit to verify the wave breaker type and the related dissipation-reflection-transmission on slopes. Finally, this study shows that there is not a biunivocal relationship between the Iribarren number, Ir, and the type of breaker, the reflection and transmission coefficients and the bulk dissipation. Therefore, Iribarren's number is not a sufficient similarity parameter for the analysis of wave breaking, and related flow characteristics on slopes.

Protecting A Low Voltage Direct Current System Using Solid-State Switching Devices for DC Grid Applications

LVDC transmission has fewer distributional losses than AC distribution, integrating renewable sources, greatly increasing the mix of clean energy sources in the standard grid in the next decade and this has become a trend that is likely to continue. As an additional benefit, DC electrical power is oftentimes seen as beneficial to applications that use cleanly generated, renewable power. Considering DC power system design, and focusing on fault protection and the systems DC circuit breaker, are system priorities. Only solid-state circuit breakers (SSCB) should be considered to obtain advanced system topography. A new type of solid state circuit breaker is being developed as a new power device for LVDC power networks to replace the EMCB. The only suitable candidate for this task is the insulated gate bipolar transistor (IGBT). Development of DC grid protection allows for the development and improvement of new power electronic devices, focusing in on the application for medium to low voltage DC grids, a rapidly acting switching function as well as fault current limiting features. To avoid nuisance tripping, fault current limiting function can be satisfactorily accomplished by extending the elapsed time using the same control circuit. This paper introduces a novel circuit breaker model for LVDC, which utilizes a coupled inductor circuit breaker, and a mathematical model of IGBT has been developed.

A Compound Current Limiter and Circuit Breaker

The protection of sensitive loads against voltage drop is a concern for the power system. A fast fault current limiter and circuit breaker can be a solution for rapid voltage recovery of sensitive loads. This paper proposes a compound type of current limiter and circuit breaker (CLCB) which can limit fault current and fast break to adjust voltage sags at the protected buses. In addition, it can act as a circuit breaker to open the faulty line. The proposed CLCB is based on a series L-C resonance, which contains a resonant transformer and a series capacitor bank. Moreover, the CLCB includes two anti-parallel power electronic switches (a diode and an IGBT) connected in series with bus couplers. In order to perform an analysis of CLCB performance, the proposed structure was simulated using MATLAB. In addition, an experimental prototype was built, tested, and the experimental results were reported. Comparisons show that experimental results were in fair agreement with the simulation results and confirm CLCB’s ability to act as a fault current limiter and a circuit breaker.