Investigation of arc roots of constricted high current vacuum arcs

Haas, W.; Hartmann, Werner

doi:10.1109/27.782266

Cited by 49 publications

(10 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The measurements of the arc velocity was done by , ) means of a high speed video camera (Phantom V7, Vision Research) for different contact diameters and arc currents, while arc root diameters were measured with a fast, single-frame, high resolution video camera [2]. A large diameter ( 200 mm) vacuum chamber used in [) these measurements allowed optical access of arc motion through a viewing port window.…”

Section: Methodsmentioning

confidence: 99%

“…(I), we get a weak dependence on ocwU: Hence, we have to make additional assumptions and/or use empirical relations for at least two more variables. The previous solutions of [1] and [2] are presented in the following, and compared to the new solution attempted in this work.…”

Section: B Momentum Balancementioning

confidence: 97%

“…QA,K= aO U I +FAK (2) The heat flux into the cathode is approximately twice as much as that into the anode due to the size of the cathode arc root [2].…”

Section: Arc Model a Energy Balancementioning

confidence: 99%

“…In particular, evaporation from the contacts and the corresponding cooling is treated quantitatively, using empirical relations from arc voltage and root diameter measurements at anode and cathode [2]. Heating, evaporation and cooling rates are determined quantitatively, in contrast to earlier work where simplifying assumptions had been made for these quantities [1], [3].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Thermodynamic Model of Moving Vacuum Arcs on Contrate Contacts

Branston

Haas

Hartmann

et al. 2006

2006 International Symposium on Discharges and Electrical Insulation in Vacuum

Self Cite

View full text Add to dashboard Cite

The behavior of constricted vacuum arcs on Radial Magnetic Field (RMF) contacts in vacuum tubes of medium voltage circuit breakers strongly determines the breaking capacity of these contact systems. The movement of these arcs under the influence of the RMF is investigated with the help of a one-dimensional (1D) thermodynamic model of the arc and its interaction with the contact surface. Heat conduction and evaporation are taken care of analytically, while the size of the arc root and, hence, its current density has been determined experimentally. The energy balance is solved by using empirical values for the respective sheath voltage drops. It is complemented by a momentum balance incorporating neutral vapor loss from the arc boundaries, which is found to be essential for the quantitative understanding of the arc physics. A time-dependent analysis of the arc properties like the arc velocity during a sine half-wave produces a good agreement with experimental values measured for different sizes of contrate contacts. The model is explained and compared to experimental results of arc velocity and experimentally determined switching capacity, respectively.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: B Momentum Balancementioning

confidence: 97%

“…QA,K= aO U I +FAK (2) The heat flux into the cathode is approximately twice as much as that into the anode due to the size of the cathode arc root [2].…”

Section: Arc Model a Energy Balancementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Thermodynamic Model of Moving Vacuum Arcs on Contrate Contacts

Branston

Haas

Hartmann

et al. 2006

2006 International Symposium on Discharges and Electrical Insulation in Vacuum

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, there is no direct experimental proof of the high surface temperatures predicted by the numerical simulation. Haas and Hartmann have only estimated the electrode temperature at the foot points of a TMF constricted arc, at anode between 3300-3600K and at cathode between 3200-3400K respectively [4]. Their findings lets appear present assumption to be reasonable.…”

Section: Introductionmentioning

confidence: 93%

Numerical simulation of a moving high-current vacuum arc driven by a transverse magnetic field(TMF)

Delachaux

Fritz

Gentsch³

et al. 2006

2006 International Symposium on Discharges and Electrical Insulation in Vacuum

View full text Add to dashboard Cite

The present modeling deals with the physical description of the high-current (>10 kA) constricted vacuum arc, driven by a transverse magnetic field (TMF), as found in vacuum circuit breakers applying TMF arc control. The MHD approach together with detailed heat transfer and evaporation equations for the electrodes are used to describe the arc behavior selfconsistently, restricting to two dimensions (2D). A newly developed model describes the cathode attachment of the constricted arc in form of a large laterally extended foot point, instead of the regular cathode spots. This model leads to the characterization of the physical quantities of the arc plasma and describes the arc motion as step-wise due to the different velocities of the current attachment areas of cathode and anode. II. PHYSICAL MODELA. Plasma zone:The present conditions allow the application of the MHD approach [1], based on the continuity equations of mass, momentum and energy, in combination with Maxwell's equations and the generalized Ohm's law. These equations are described in [2], and are similar to that of [3]. As usual, the plasma is regarded as quasineutral and consists of interpenetrating fluids of heavy species (ions and neutrals) and of electrons. The mass equation considers the rate equations for Cu, Cu+, Cu++ and Cu++, and it includes the process of ion production and loss by electron impact and recombination due to three body collisions. The fluids of heavy species and electrons have temperatures T and Te, convection velocities u and ue, and pressures p and Pe, respectively.

show abstract