scholarly journals Investigation and Numerical Simulation of a High-Current AC Circuit Breaker

2019 ◽  
Vol 6 (3) ◽  
pp. 235-238
Author(s):  
I. Murashov ◽  
V. Frolov ◽  
A. Kvashnin ◽  
J. Valenta ◽  
D. Simek ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
High Speed ◽  
Circuit Breaker ◽  
Moving Mesh ◽  
Electrical Characteristics ◽  
High Current ◽  
Spectral Diagnostics ◽  
Current Voltage ◽  
Time Calculation

The article is devoted to the study of the high-current AC circuit breaker. The results of the study are presented for various configurations of the arc divider. The study includes methods of spectral diagnostics and high-speed camera shooting synchronized with the electrical characteristics of the circuit breaker (current, voltage) in time. The obtained results allow to determine the composition of the plasma and dynamics of changes in the composition of the discharge in time. Calculation of the plasma composition and properties is made according to the obtained data, which makes it possible to take into account the products of circuit breaker materials ablation in numerical simulation. Non-stationary two-dimensional mathematical model with a moving mesh is developed. The obtained results allow to correct and verify the developed mathematical model of the circuit breaker operation. The evaluation of the arc divider influence is presented in the article.

scholarly journals Mechanisms Responsible for Arc Cooling in Different Gases in Turbulent Nozzle Flow

2017 ◽  
Vol 4 (3) ◽  
pp. 234-240 ◽  
Author(s):  
Y. Guo ◽  
H. Zhang ◽  
Y. Yao ◽  
Q. Zhang ◽  
J. D. Yan
Keyword(s):  
Material Properties ◽  
High Speed ◽  
Gas Flow ◽  
Ohmic Heating ◽  
Circuit Breaker ◽  
Fault Current ◽  
High Current ◽  
Physical Mechanisms ◽  
Current Zero ◽  
Different Gases

A high voltage gas blast circuit breaker relies on the high speed gas flow in a nozzle to remove the energy due to Ohmic heating at high current and to provide strong arc cooling during the current zero period to interrupt a fault current. The physical mechanisms that are responsible for the hugely different arc cooling capabilities of two gases (SF<sub>6</sub> and air) are studied in the present work and important gas material properties controlling the cooling strength identified.

Verification of Near-Interface Traps Models by Electrical Measurements on 4H-SiC n-Channel Mosfets

2013 ◽  
Vol 740-742 ◽  
pp. 533-536 ◽  
Author(s):  
Viktoryia Uhnevionak ◽  
Christian Strenger ◽  
Alex Burenkov ◽  
Vincent Mortet ◽  
Elena Bedel-Pereira ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Fixed Charge ◽  
Interface Traps ◽  
Electrical Characteristics ◽  
Electrical Measurements ◽  
Mobility Degradation ◽  
Current Voltage ◽  
Degradation Models ◽  
Electrical Data

4H-SiC n-channel lateral MOSFETs were manufactured and characterized electrically by current-voltage measurements and by numerical simulation. To describe the observed electrical characteristics of the SiC MOSFETs, Near-Interface Traps (NIT) and mobility degradation models were included in the simulation. The main finding of the simulation is that two models for the NIT states in the upper part of the SiC bandgap are able to describe the electrical data equally well. In one of them, acceptor-like traps and fixed charge are considered while in a newly developed one, donor-like traps are taken into account also.

scholarly journals Approximate Single-Diode Photovoltaic Model for EfficientI-VCharacteristics Estimation

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Jieming Ma ◽  
Ka Lok Man ◽  
T. O. Ting ◽  
Nan Zhang ◽  
Sheng-Uei Guan ◽  
...  
Keyword(s):  
High Speed ◽  
Model Simulation ◽  
Approximate Model ◽  
Electrical Characteristics ◽  
Modeling Methods ◽  
Proposed Model ◽  
Current Voltage ◽  
Iterative Procedures ◽  
Behavior Models ◽  
Simulation Time

Precise photovoltaic (PV) behavior models are normally described by nonlinear analytical equations. To solve such equations, it is necessary to use iterative procedures. Aiming to make the computation easier, this paper proposes an approximate single-diode PV model that enables high-speed predictions for the electrical characteristics of commercial PV modules. Based on the experimental data, statistical analysis is conducted to validate the approximate model. Simulation results show that the calculated current-voltage (I-V) characteristics fit the measured data with high accuracy. Furthermore, compared with the existing modeling methods, the proposed model reduces the simulation time by approximately 30% in this work.

scholarly journals Influence of Varying Gaps Between TMF Contacts on Constricted High Current Vacuum Arcs

2019 ◽  
Vol 6 (1) ◽  
pp. 103-106
Author(s):  
B. Kühn ◽  
B. Weber ◽  
D. Gentsch ◽  
M. Kurrat
Keyword(s):  
High Speed ◽  
Industrial Development ◽  
Circuit Breaker ◽  
Metal Vapor ◽  
High Speed Camera ◽  
High Current ◽  
Medium Voltage ◽  
Vacuum Circuit Breaker ◽  
Vacuum Test ◽  
Transversal Magnetic

The behavior of high current arcs in vacuum circuit breaker (VCB) is interesting for research and industrial development purpose which lead to further products. To improve the interruption capability of VCB, two approaches to control the arc have been proven successful. Applying transversal magnetic fields (TMF) on the arc is use for industrial VCB in medium voltage ranges. For greater gap distances the behavior of the arc is less thoroughly investigated. <br /> In this paper, the appearance of metal vapor arcs drawn by common TMF contacts in a vacuum-test-interrupter is investigated. An adapted drive mechanism enables to interrupt a fixed current with varying gaps from 5 to 25 mm and a constant opening time. Breaking operations with a 50 Hz current are observed with a high speed camera. With increasing gap distance a changed arc appearance can be observed. The goals of this work are to be understood as a feasibility study for optical evaluation methods for vacuum arcs under TMF.

Hydrodynamic Performance and Appendage Considerations of Wave-Piercing Planing Craft Overlapping Waves and Porpoising

2019 ◽  
Author(s):  
Sang-Won Kim ◽  
Sang-Eui Lee ◽  
Gyoung-Woo Lee ◽  
Kwang-Cheol Seo ◽  
Nobuyuki Oshima
Keyword(s):  
Numerical Simulation ◽  
Pressure Distribution ◽  
High Speed ◽  
Numerical Study ◽  
Hydrodynamic Performance ◽  
Moving Mesh ◽  
Navier Stokes ◽  
Hull Form ◽  
Wave Condition ◽  
Planing Craft

Abstract This work addresses the numerical study of wave-piercing planing hull and related hydrodynamic performance as the appendages. From the half century ago, the interest in high-speed planing crafts has been advanced toward maintaining performance stably. The main reasons to make it hard are instability motion occurring from porpoising and wave condition. Porpoising is mainly due to overlap the heaving and pitching motion with certain period, which is caused by instable pressure distribution and changing longitudinal location of center of gravity. In addition, in wave condition, encountering wave disturbs going into planing mode. This paper presents numerical results of wave-piercing planing hull in porpoising and wave condition. Numerical simulation is conducted via Reynolds Averaged Navier-stokes (RANS) with moving mesh techniques (overset grid), performed at different wave condition. The results for the behaviors of wave-piercing hull form are practically presented and investigated in this study. The understanding of these phenomena is important for design of appendages of wave-piercing hull-form.

scholarly journals Analysis of Electromagnetic Processes Inside the Arc Interrupting System of a High-current Circuit Breaker

2017 ◽  
Vol 4 (2) ◽  
pp. 161-164 ◽  
Author(s):  
I. Murashov ◽  
V. Frolov ◽  
D. Ivanov ◽  
A. Kvashnin
Keyword(s):  
Mathematical Model ◽  
Short Circuit ◽  
Circuit Breaker ◽  
Electric Arc ◽  
High Current ◽  
Electromagnetic Processes ◽  
Contact Position ◽  
Short Circuit Currents

Description of electromagnetic processes inside an arc interrupting system of high-current circuit breaker is presented in article. Non-stationary mathematical model of the circuit-breaker operation (short-circuit currents mode) is developed. The main regularities of the displacement of the electric arc inside an arc chute are established. The influence of the movable contact position on the conditions for the displacement of the electric arc is presented. Also, the influence of the arc chute material on the motion and interrupting of an electric arc (alternating and direct currents) is established.

Numerical simulation of bubble dynamics in central region of streamer

2018 ◽  
Vol 13 (3) ◽  
pp. 11-22 ◽  
Author(s):  
A.A. Aganin ◽  
A.I. Davletshin ◽  
T.F. Khalitova
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Central Region ◽  
Cavitation Bubble ◽  
High Speed ◽  
Hydrodynamic Interaction ◽  
Bubble Dynamics ◽  
Numerical Technique ◽  
Spherical Bubbles ◽  
Strong Expansion

A mathematical model and a numerical technique for studying strong expansion and collapse of cavitation bubbles located in the central region of a streamer where the bubbles are almost motionless are developed. They are essentially efficient combinations of the models and techniques previously created by the authors for calculating the dynamics of interacting weakly-non-spherical bubbles in a streamer and the dynamics of a single axisymmetric bubble. The first model and technique are applied at the low-speed stage of expansion and compression of bubbles where their hydrodynamic interaction is significant. The second ones are used at the final high-speed stage of their collapse where the interaction is inessential. The simplest case of the streamer comprising three bubbles is considered as an example to illustrate the features of the developed model and numerical technique. It is shown that under the strong expansion and collapse of an initially spherical cavitation bubble, the presence of neighboring bubbles can substantially deflect the bubble cavity vapor dynamics from what is realized inside a similar but single bubble.

Analysis of electrical characteristics of the four-quadrant converter in high speed train considering pantograph-catenary arcing

2016 ◽  
Vol 231 (2) ◽  
pp. 185-197
Author(s):  
Fei Lin ◽  
Xiaofan Wang ◽  
Zhongping Yang ◽  
Hu Sun ◽  
Wenzheng Liu ◽  
...  
Keyword(s):  
Direct Current ◽  
High Speed ◽  
Electrical Characteristics ◽  
High Speed Train ◽  
Arc Model ◽  
Output Torque ◽  
Current Voltage ◽  
Direct Current Voltage ◽  
Contact Surfaces ◽  
Four Quadrant

Pantograph–catenary disconnection occurs quite frequently in high-speed situations. Pantograph arcing has a significant impact on the contact surfaces and power quality. This article focuses on the effect on the electrical characteristics of the four-quadrant converter of pantograph arcing. An arc model which combines Cassie’s arc model with Mayr’s arc model is built. This article mainly researches the influence of the pantograph arcing on the four-quadrant converter in different durations. Pantograph arcing leads to voltage pulse in voltage, as well as the harmonics in the current of the alternating current side. At the same time, the direct current voltage decreases when the arc occurs. Therefore, it can ultimately decrease the output torque and increase the torque pulsation of the motor.

Study of anode spot transient processes of a high-current vacuum arc with high-speed spectroscopy and videorecording

2021 ◽  
Vol 64 (1) ◽  
pp. 112-117
Author(s):  
A.V. Schneider ◽  
◽  
S.A. Popov ◽  
E.L. Dubrovskaya ◽  
A.Y. Yushkov ◽  
...  
Keyword(s):  
High Speed ◽  
Arc Discharge ◽  
Circuit Breaker ◽  
Vacuum Arc ◽  
Charge Composition ◽  
High Current ◽  
Anode Region ◽  
Anode Spot ◽  
Vacuum Circuit Breaker ◽  
Switching Characteristics

The processes of plasma formation in the anode region of a high-current vacuum arc discharge are of high actuality in terms of improving the switching characteristics of vacuum circuit breaker. In present paper the dynamics of the radiation spectrum of anode region was recorded with the system that allows time scanning of a spectrum. In parallel, there was high-speed videorecording. The obtained data clearly show changes in the charge composition of the anode spot plasma in the process of changing discharge forms.

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