Arc Reignition Research Articles

Study on the influence of transverse magnetic field on the arc and reignition characteristics of HVDC relays

It is of great significance to clarify the influence of transverse magnetic field (TMF) on arc control in high-voltage direct current (HVDC) relays. In this paper, the influence of TMF in a wide range of 0–140 mT on the arc characteristics of HVDC relays is studied, the experimental observations of arc reignition are carried out and the effect of arc reignition on contact erosion, the criterion of arc reignition and the mechanism of TMF enhancement on arc reignition are further analyzed. The results show that the TMF enhancement is beneficial for shortening the arc voltage stagnation duration and accelerating the speed of arc elongation, arc dispersion and dispersed arc motion, thereby improving the arc extinguishing performance. However, higher TMF leads to more severe and earlier arc reignition, as also shown in the experimental observations. The arc reignition further causes a sudden drop in arc voltage, prolonged arc duration and uneven contact erosion. To evaluate the occurrence of arc reignition caused by TMF enhancement, a simplified breakdown criterion is proposed through the defined characteristic variable C¯(t) . Based on this, the mechanism by which the TMF enhancement more easily causes arc reignition is explained, that is the higher TMF leads to an earlier and faster increase in C¯(t) and slightly reduces the breakdown threshold C¯∗(t5,D) . Further, measures to suppress the arc reignition are proposed.

Extended Pantograph–Catenary Arc Modeling and an Analysis of the Vehicular-Grounding Electromagnetic Transients of Electric Multiple Units

As the operating speed of electric multiple units (EMUs) in high-speed railways increases, pantograph–catenary (PC) detachment arcing occurs frequently. The resulting vehicular-grounding electromagnetic transients are related to the dynamic characteristics of the arc length. During large detachment, the processes of arc extinction and arc reignition may occur, resulting in more severe train body (TB) over-voltages and adverse effects on some vehicular electronic devices. As an extension of the previous works, this paper aims to establish a suitable PC arc model to examine the TB transient voltages. To begin with, the arc length dynamic characteristics are reasonably analyzed to deduce the relationship between the detachment distance and the arc length via the chain arc model. Then, the dynamic characteristics of the arc length are introduced, and an arc modeling scheme is proposed to elaborate the vehicle-grid electric power model for EMUs encountering various arcing scenarios. Based on this, the transient over-voltages are analyzed, accounting for both the arc extinction and arc reignition, as well as the mutual influences of multiple detachments in a short time. The influential factors, including arc length characteristics, phase angle, excitation inductance, and grounding parameters, are also involved in the performed analyses.

Defect recognition of oil‐pressboard insulation based on frequent arc reignition phenomenon under switching impulse voltage

AbstractIn the past three years, a number of oil‐immersed ultra‐high‐voltage shunt reactors have experienced discharge defects when being put into operation, resulting in an overload of acetylene. However, detecting and identifying these discharge defects caused by switching impulse voltage is challenging under steady‐state conditions. This poses unpredictable and difficult‐to‐assess safety risks for the longterm operation of the equipment and subsequent transient processes. Hence, comprehending the discharge behavior of oil‐pressboard (PB) insulation under switching impulse voltage and devising a method to identify defects becomes crucial. This study focuses on investigating the frequent arc reignition (FAR) pattern exhibited by typical defects under both standard and oscillation switching impulse voltages. The objective is to uncover the mechanism behind FAR and propose a defect recognition strategy suitable for transient processes. The study reveals the FAR process will occur at least once during the breakdown process; the FAR phenomenon is the weakest in the surface defect with a weak vertical electric field. The average recovery voltage percentage and the average discharge interval of the FAR process decrease with increasing impulse amplitude or oscillation frequency. Additionally, the average number of discharges decreases with higher oscillation frequency, while it initially increases and then decreases with increaseing amplitude. Based on the analysis of the number of FAR processes and their variation in terms of amplitude or discharge interval, a method for recognizing oil‐PB defects during switching transient processes is developed and successfully applied to a case study involving acetylene overload in a 1000 kV shunt reactor.

Combined Effect of the Parameters of Vacuum Interrupter and L-C Circuit Upon Arc Re-Ignition in HVDC Circuit Breakers

Combined Effect of the Parameters of Vacuum Interrupter and L-C Circuit Upon Arc Re-Ignition in HVDC Circuit Breakers

A novel triple capacitor multi-level submodule MMC topology with fault current clearing capability

In the high voltage direct current system based on modular multilevel converter (MMC-HVDC), the half-bridge submodule (HBSM) has become the preferred submodule for significant projects due to its convenient control and low cost. However, the DC short-circuit protection performance of MMC-HVDC will seriously restrict its development in areas such as overhead lines, high voltage, and large capacity. This article proposes a triple capacitor multi-level submodule (TCMSM) topology of modular multilevel converter with DC fault-blocking capability. It utilizes at least one-third of the module capacitance in the bridge arm to reverse to suppress DC fault current and turn off the diode. At the same time, the unidirectional conductivity of the diode can also prevent arc reignition at the fault point. The article also conducted in-depth research on the DC short-circuit fault elimination mechanism of this topology, and compared its performance with other topologies. Through analysis, it can be concluded that TCMSM reduces the initial investment and operating costs by reducing the number of devices inside the module while possessing the fault current blocking ability. Finally, MATLAB/Simulink was used to simulate and verify the proposed new topology, and its performance was analyzed.

Study on impact of gap difference on plasma distribution of direct current vacuum circuit breaker with double-break

During the fault current breaking process of a mechanical direct current vacuum circuit breaker (DC VCB) with double-break (DB), the mechanism’s dispersion can result in a gap difference between the two breaks. A DB DC VCB breaking experiment platform is constructed in order to investigate the impact of gap difference on plasma distribution during the DB DC VCB breaking process. During the experiment, a high-speed camera is used to capture the vacuum arcing process at the two breaks under varying gap difference conditions. Then, the arc feature parameters and their variations during the zero-zone process are extracted using image processing techniques, and the distribution patterns of plasma and arc energy at the two breaks are analyzed and compared. When there is no gap difference between the two breaks of the experimental DB DC VCB, there are no significant differences in arc energy and the sizes of high-, medium-, and low-temperature plasma zones between the two breaks. When there is a gap difference between two breaks, the break with the smaller gap has larger high and medium-temperature plasma zones, more concentrated arc energy, higher particle concentration, lower arc diffusion velocity and arc energy decay velocity, and a greater amount of residual plasma after the extinguishing of the arc. When the gap difference exceeds a certain threshold, energy spots appear on the contact surfaces, and a high concentration corridor of residual particles remains between the contacts after the current crosses zero, forming a breakdown weak point that eventually leads to arc re-ignition (hence interruption failure) under the action of transient recovery voltage.

Investigation on Multiple Reignitions Caused by Vacuum Circuit Breaker Switching Off Shunt Reactor Considering Contact Travel in Offshore Wind Farms

The dielectric recovery strength (DRS) of vacuum circuit breaker (VCB) interrupter is closely related to the travel characteristic of contact, which determines the overvoltage caused by switching off shunt reactor (SR) in offshore wind farm (OWF). Firstly, the travel characteristic of contact is analyzed in detail. A field experiment of 35 kV substation is performed and the relationship between contact travel and DRS in different periods is obtained. Then, a novel VCB model considering the travel characteristic is proposed and used to study the arc behavior of the VCB interrupter. The mechanism of multiple reignitions and the sensitivity analysis for switching overvoltage are discussed. Finally, a hybrid method of grey relational grade (GRG) and response surface method (RSM) is employed to optimize the contact travel in order to suppress arc reignition. A group of optimal travel parameters of VCB contact are obtained for minimizing the overvoltage peak.

Simulation and Protection of Reignition Overvoltage in Wind Farm Considering Microscopic Dielectric Recovery Process of Vacuum Circuit Breaker

The high amplitude and steep overvoltage generated by the breaking of the vacuum circuit breaker in the wind farm damages the inter-turn insulation of the transformer. There is a certain difference between the simulation results of the traditional reignition model and the measured overvoltage. It is necessary to improve the simulation model to simulate the overvoltage condition of the transformer more accurately and then select appropriate overvoltage protection measures. In this paper, based on the physical process of dielectric recovery during the opening process of the vacuum circuit breaker, a model of dielectric strength recovery is built to simulate the arc reignition of the vacuum circuit breaker. The model was applied to compare the overvoltage protection effects of RC snubbers, surge arresters, and choke coils. The simulation results show that the overvoltage amplitude and reignition times calculated by the model proposed in this paper are closer to the measured values. Compared with the traditional linear curve reignition model, the accuracy was increased by 24% and 51.2%, respectively. The parameter value of RC snubbers, the connection mode of surge arresters, and the combination mode of choke coil have an influence on overvoltage suppression. Finally, a suitable suppression scheme is proposed by installing a combined arrester on the high-voltage side of the transformer and connecting a choke coil in series, which can limit the phase-to-ground voltage and the phase-to-phase voltage to 2.43 p.u and 3.24 p.u, respectively, and reduce the steepness from 157.2 kV/μs to 22.3 kV/μs.

Research on VFTO Simulation Analysis of 1000 kV GIS Test Circuit Considering Dynamic Arcing Model

In the research process of very fast transient overvoltage (VFTO), the accuracy of the switching arc model largely determines the calculation results of VFTO. How to more accurately simulate the arc striking and extinguishing process of the arc during the action of the disconnector is the key issue in the study of the arc model. In this article, the ATP-EMTP electromagnetic transient program was used to simulate arc damping with a series connection of a fixed-value resistance and a time-varying inductance, and the built-in MODELS module was used for programming to simulate the reignition and extinguishing process of the arc based on the gaseous dielectric theory and the energy balance theory. The model was applied to a 1000 kV gas insulated substation (GIS) test circuit. The relationship between the arc damping and arc voltage and current was analyzed, and the arc reignition law during opening and closing is studied. The arcing law obtained is compared with the experimental results of the existing literature, and the accuracy of the simulation model is verified. Simultaneously, the influence of the opening speed of the disconnector on VFTO was analyzed by simulation. The results show that when the opening speed is less than 0.7 m/s, the maximum value of VFTO in the test circuit increases with the increase in opening speed. After the VFTO amplitude reaches the maximum and continue to increase the opening speed, the VFTO amplitude decreases. This law is consistent with the experimental results of the existing literature, which proves that the arc model built in this article has a certain engineering application value.

Hybrid plasma modeling of the interaction between the vacuum arc jet and the hot metallic particle near the current zero

In this paper, the interaction between the vacuum arc plasma jet and the hot metallic particle near current zero was investigated by numerical simulation. A vacuum arc plasma jet model was developed using the hybrid simulation method, in which electrons were considered as a massless fluid, while heavy particles such as atoms and ions were modeled as particles. In this model, the effect of the evaporation of metal atoms from the metallic particle was considered. Additionally, the Monte Carlo collision method was used to model inelastic collisions between electrons and heavy particles. The simulation results demonstrate that the metallic particle blocks the plasma jet, causing an asymmetric and nonuniform distribution in the plasma jet. Furthermore, some of the evaporated atoms from the hot metallic particle are converted into Cu1+ ions by ionization collisions with electrons. The drift velocity of Cu1+ ions coming from the ionization of metal vapor is much lower than that of highly energetic ions emitted from the cathode spot, making it difficult for them to be completely dissipated as soon as possible during the extinguishing phase. Moreover, the presence of a hot metallic particle causes an increase in the density of plasma in its surroundings, which increases the probability of arc reignition in the post-arc phase.

Characteristic analysis of the VCB operational overvoltage for high-speed trains considering arc reignition phenomenon

ABSTRACT Due to the constant pursuit for higher operating velocity, the traction power capacity for high-speed trains needs to be enlarged. When the train passes approach the insulating sections set between the two neighbouring contact lines carrying the traction current with different phases, the vehicle-mounted vacuumed circuit breaker (VCB) needs to be switched off. Generally, the arc may generate when connecting or separating the contacts, when switching on or off the VCB. In order to investigate the characteristics of the reignition overvoltage the ‘train-rail-catenary’ traction power supply model considering the reignition process between the VCB’s contacts is launched in this paper. The impact of the dielectric strength recovery rate between the contacts of the VCB on the number of reignition and the amplitude of the reignition overvoltage is analysed based on the experimental and simulation results. Ultimately, the corresponding restraining measures are proposed for suppressing the reignition overvoltage.

Characteristics of pantograph‐catenary arc under low air pressure and strong airflow

Pantograph-catenary arc fault is the primary factor threatening the stability of the power transmission for high-speed railway. The motion characteristics of the pantograph-catenary arc under low air pressure and strong airflow is significantly different from the case under atmospheric pressure. In this paper, an experimental platform of pantograph-catenary arc was built to investigate arc root position-time and arc column longitudinal drift height-time characteristic curves under different air pressures and airflow velocites. Via analysing the corresponding results, it can be found that there are different arc root–arc column traction mechanisms at different stages of arc development. The arcing time and arc root stagnation time under low air pressure are significantly longer than the case under atmospheric pressure, resulting in more serious electrode ablation. The arc column longitudinal drift velocity and height are greater with the increase of airflow velocity. Two typical irregular arc motion phenomena—arc root jumping and arc reignition are observed. To clarify the internal mechanism of the above phenomenon, a magnetohydrodynamics (MHD) model of the pantograph-catenary arc was lauched, the influence mechanism of the pantograph-catenary arc temperature and voltage are studied, and the physical process of arc temperature oscillation is analysed. The research results provide theoretical support for arc protection in high-altitude areas.

Phasor-Based Single-Phase Auto-Reclosing Scheme for Non-Compensated Transmission Lines

An approach to detect the secondary arc extinction is proposed here for single-phase auto-reclosing of non-compensated transmission lines. It consists on the analysis of the line side voltage phasors in the modal domain to safely and rapidly identify the presence and the extinction of secondary arc in the line. The procedure can also determine the arc re-ignition if it occurs during the line dead time. Since the proposed approach requires only the voltage phasors at one line terminal, it can be easily implemented in existing Intelligent Electronic Devices (IEDs) with no additional hardware or equipment requirement. Data from the Brazilian Power Grid were used to generate the case studies through the Electromagnetic Transients Program (EMTP). Moreover, field recordings were used to validate the proposed approach. A qualitative comparison with existing methods was accomplished and the obtained results reveal the proposed scheme efficiency, reliability and robustness.

Experimental Investigation of the Breaking Arc Behavior and Interruption Mechanisms for AC Contactors

For alternating current (ac) contactors, the direct consequences of breaking arcs are material erosion and its associated electrical contact failure. In this article, the ac arc of a commercial contactor is simulated experimentally and the relevant arc characteristic parameters are recorded. The effects of contact gap and point-on-wave at break (POW) on arc behavior, including arc voltage, conductance, arc duration, and termination voltage are investigated. In particular, the arc reignition phenomenon at small contact gaps is observed and explained. Finally, two interruption mechanisms of the ac arc (zero-crossing termination and mechanical ruptured termination) are revealed based on the variations in arc termination voltage as a function of POW.

A lumped-parameter model for sound generation in gas metal arc welding

It is found that the welding sound generated in Gas Metal Arc Welding (GMAW) can help human welders to improve welding quality; however, little work has been reported on the sound generation and prediction in GMAW processes. To investigate the sound generation in GMAW, this paper proposes a lumped-parameter model to predict the sound signals at the short-circuiting mode in GMAW, where the power source is modeled by a simple resistor–inductor electrical circuit and the metal droplet dynamics is modeled by a mass-spring model. The simulation results of the welding current, arc voltage, and sound signals are found to be in a reasonable agreement with the experimental measurements. Both simulation and experiment results show that the welding current increases from a base value in the arcing phase to a peak value in the short-circuiting phase first and then slumps to the base value; the voltage is close to zero in the short-circuiting phase corresponding to the current peaks and fluctuates in the arcing phase due to the uncertainties in the arc resistance; and an acoustic impulse is formed at each peak current and valley voltage in the short-circuiting phase, indicating that the sound generation is related to the energy release during the arc re-ignition process. The proposed lumped-parameter model can be used to investigate the effect of the input welding parameters on the welding sound.

Arc characteristics in short electrical arc high-efficiency milling for GH4169

To solve core problems of slow arc response and unstable combustion, arc movement characteristics and arc action rules in short electrical arc milling are studied using a high-speed acquisition system and the Phantom high-speed camera in this article. To improve arc reignition, the characteristic parameters of arc discharge are determined as a discharge gap of 0.053 mm and discharge time of 2180 μs. A short electrical arc milling experiment with nickel-based superalloy GH4169 is carried out, confirming that the continuous stable discharge of the arc can easily produce a material removal rate of 40 g/min and a tool wear ratio of 0.8%. An SU8010 scanning electron microscope and energy spectrum analyzer are then used to study the erosion mechanism of GH4169 in short electrical arc milling. This article aims to expand the processing range of short electrical arc machining in the field of special material processing to provide experimental and theoretical bases for the development of short electrical arc milling technology theory and methods.

Electromagnetic interference characteristics during switching operation in power distribution network

The disturbance problem caused by the transient electromagnetic field during high-voltage switching operation is the most typical. Electromagnetic interference can be coupled to the secondary circuit in a conductive and radiating manner, then, affects the reliability of the secondary-side circuit. The key to the simulation calculation of the operating switch overvoltage is the judgment and simulation of its opening and closing conditions. The arc current zero-crossing judgment signal, the arc extinguishing and reignition judgment signals are fused, and a control signal is recursively obtained for switching operation. By analyzing the transient process during switch operation, a simplified model for isolating and closing the no-load bus, an overvoltage calculation model, and a fast transient model for overvoltage time-frequency signals are established. The characteristics of the transient electromagnetic field generated when the no-load bus and the circuit breaker of the disconnector are charged to the no-load transformer are simulated. The mechanism of fast transient pulse group generated by switching operation is obtained. The maximum overvoltage amplitude generated during the disconnector’s switching, and the no-load bus is obtained by simulation. Comparing with the measured data, the laws of electromagnetic interference characteristics during switching operation in power distribution network are verified.

Suppression Measures for Overvoltage Caused by Vacuum Circuit Breaker Switching Off 10-kV Shunt Reactor

During the process in which a vacuum circuit breaker (VCB) switches off the shunt reactor (SR), an overvoltage with high amplitude and high frequency (HF) will occur because of current chopping and multireignition. To reproduce this switching overvoltage faithfully, the voltage and current characteristics of the VCB were analyzed in this work, based on the field test data from a 220-kV substation in Chongqing, China. Then, typical parameters of three basic factors mentioned in Helmer's VCB model, chopping current value, dielectric dynamic insulation strength, and HF current quenching capability, were selected after statistical analysis and an arc reignition model of VCB was established. Based on this presented model, the influences of the surge arrester, the resistor–capacitor (RC) snubber, and the installation positions and quantities of these protective devices on overvoltage suppression performance were studied in simulation. In addition, the field test using the surge arrester and the RC snubber as the suppression measures was performed again in the same substation. Finally, we derived the conclusion that the most suitable suppression scheme for overvoltage caused by VCB switching off 10-kV SR is installing two 12/32.4 kV surge arresters at the terminals of the cables for the SR and the substation transformer (ST).

Modelling a Disconnect Switch

Abstract This article presents a model to simulate disconnecting switches in transient studies. The distance between contacts of a disconnecting switch does not change instantaneously; it takes several seconds to complete the full movement from closed to open, or vice-versa. The disconnecting switches are able to operate with lower current amplitudes, so a disconnecting switch is operated only when the circuit breaker is in open position. However, even with the circuit breaker open, there is a current flowing through the grading capacitors. The grading capacitors in conjunction with the busbar capacitance form a capacitive divider, and there is a floating voltage in the busbar. When the contacts of the disconnecting switch move, the withstand voltage varies and an electric arc appears. This arc is unstable and is interrupted and reignited several times. Each arc reignition causes a sudden voltage change that propagates through the busbar and impacts any connected equipment. The developed model, with the withstand voltage variation and the electric arc behaviour taken into account, calculates the fast transient overvoltages originated during a disconnecting switch operation. The amplitude and waveform of these overvoltages may then be used to evaluate the impact on insulation ageing.

Development of switching performance evaluator and arc modelling tool for low-voltage switching devices

PurposeThe purpose of this paper is to investigate a reliable evaluator of arc re-ignition and to develop a numerical tool for accurate prediction of arc behaviour of low-voltage switching devices (LVSDs) prior to empirical laboratory testing of real products.Design/methodology/approachTwo types of interruption tests have been carried out in the investigation of re-ignition evaluators. Arc modelling tool coupled with the load circuit has been developed to predict arc characteristics based on conventional magnetohydrodynamics theory, with special attention given to Lorentz force acting on the arc column and surface phenomena on the splitter plate. The model assumptions have been validated by experimental observation of arc motion and current and voltage waveforms.FindingsIt is found that the exit-voltage across the switching device and the ratio of system to exit-voltage at the current zero point are reliable evaluators for prediction of re-ignition. Where the voltage ratio is positive, instantaneous re-ignition does not occur. Further, the probability of re-ignition is very low if the voltage ratio is in the rage of −1.3 to 0.Originality/valueIt is observed that the voltage ratio can be considered as a reliable global evaluator of re-ignition, which can be used for various types of LVSD test conditions. In addition, it is shown that arc modelling allows a good prediction of the current and voltage waveforms, arc motion as well as the exit-voltage, which can be used to obtain the evaluator of re-ignition.