Dynamic Arc Model Research Articles

Dynamic arc modeling of pollution flashover of insulators under DC voltage

A dynamic model that computes the flashover voltages of polluted insulators energized with DC voltage is presented. The salient feature of this model is that it takes into account the configuration of the insulator profile at every instant, which plays an important role in the flashover process of the DC polluted insulators. A number of practical insulator geometries have been studied, and the validity of the model is verified by comparing the computed results with the experimental results of previous researchers. >

The Computer Analysis of Switching Transients Involving ARC Model

The objective of this paper is to study the relevance of computerised modelling technigues to the solution of switching transients involving dynamic arc. The system is to be represented by a set of mathematical equations by the Rung-Kutta-England numerical technique and the nonlinear dynamic arc model is to be used as the circuit element. The work is concerned with the analysis of the transient recovery voltage (TRV) created by th^ cable-connected busbar fault current interruption in distribution system. In this paper, a new analytical method has been developed for solving this problem: the modified DOMMEL method. The TRV in the I.E.C. standards was compared with the more accurate simulation developed in this paper for the case of the cable-connected bus fault. In particular, the wave form of the TRV is similar to that of the short line fault on the transmission line which imposes a severe duty on the circuit breaker due to the high initial rate of rise of the voltage across the circuit breaker. The results indicated large differences and it issuggested that the I.E.C. standard needs modification.

Derivation of Circuit-Breaker Parameters by Means of Gaussian Approximation

Dynamic arc models describe the circuit-breaker in its individuality by empirical parameters that have to be derived from current zero oscillograms. In case of the Urbanek model the differential equation for the arc conductance can be generally integrated because only four constant parameters used. For that case the empirical constants can be derived by Gaussian approximation of the empirically obtained arc conductance (from a current zero oscillogram) by the arc model.

Study of the effects of gas flow on the performance of gas-blast circuit breakers

Experiments were carried out at a Siemens laboratory with specially designed circuit breakers to investigate the relationship between gas flow and arc behavior for various shapes and arrangements of gas nozzles, as well as for different types of gas and pressure conditions. The current, post-arc current, and voltage measurements were supplemented by the employment of optical methods. By using a high-speed schlieren camera, it was possible to obtain valuable information on the flow characteristics and density of the gas surrounding the arc and to estimate the influence of these quantities on the arc-quenching capacity of a breaker. The interaction of the electric power system and the arc could also be taken into account by using a dynamic arc model.