Simulacion Horno De Arco Electrico Atp

Arc Furnace Modeling in ATP-EMTP
E. A. Cano Plata, Member, IEEE, and H. E. Tacca, Member, IEEE
Then a simpler, quasi-empirical model is proposed in order to obtain an easy method to analyse the arc furnace by way of analytical expressions. The second model is intended to be a simpler option. This simplification is achieved supposing the transformer reactance to be linear. So, the saturation andthe hysteresis effect on the transformer are not taken into account in this model; then analytical expressions will be achieved and the study is quick and easy. A deeper simplification is made with regard to the last model. The wave-shape of the arc voltage-current is supposed to be piece-wise linear and the resistance of the impedance is neglected. In this way the third approximate model isshown. In the models special attention is paid to the current and power in the arc because they are closely related to the flicker and harmonic study. The results for each model are compared with a real arc furnace; pqAT[2-3] is being used in order to get a validation method. II. ARC FURNACE CIRCUIT The main furnace elements are shown in Fig. 1. These are: Transformer reactance, power cable and arcsource (the electrodes).

Abstract1— The use of the arc furnace and its influence on the power system is being studied. A set of models that allows for the evaluation of the electrical behavior during steady state is presented in this paper. These models have different levels of complexity; starting by taking into account all the non-linearities of the arc furnace circuit, passing throughneglecting the nonlinearities of the transformer reactance and supposing that the wave shape of the voltage-current characteristic in the arc is piece–wise linear. Experimental results are presented and used to validate them. Index Terms-- Harmonics, power quality, EMTP simulation, wavelet transform, instantaneous power.

I. INTRODUCTION t is recognized that one of the main sources of harmonic, flickerand unbalance are found in arc furnace. These three phenomena are problems of power quality that affect our daily lives. These problems have their origins in the non linear linking of the load that is connected to the power system. The utilities and their potential users that have this type of equipment should have a method that permits the evaluation of this type of problem. As the behavior ofthe arc furnace from the electromagnetic view point is not strictly periodic, it cannot be analyzed with precision using the Fourier series and harmonics [1]. Sometimes they can be considered as transient loads for which the flicker is a greater problem than the harmonics [4]. For this reason this paper will be using the electromagnetic transient program ATP [12]. This paper will attempt to coverthe study of the arc furnace from the power quality point of view and for this reason three models will be present. First, the complete model is presented. In this model, the most important non-linearities of the arc furnace systems are represented. These are the saturation and hysteresis effect on the transformer, the power cable, and the arc phenomenon inside the furnace. An iterative method isneeded to aggregate a random signal (resistance parameter) in this approximation.
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This work was supported in part by the National University of Colombia and Department of Electronics, Engineering Faculty at the University of Buenos Aires. E.A. Cano Plata is with National University of Colombia, Manizales, Colombia, A.A. 127 (e-mail: ecano@fi.uba.ar). H. E. Tacca is with the Department ofElectronic Engineering, University of Buenos Aires, Buenos Aires - Argentina, C.P. 1063, Paseo Colón 850 piso 1. (e-mail: htacca@fi.uba.ar).

Fig 1. Arc furnace equivalent circuit.

Presented at the International Conference on Power Systems Transients (IPST’05) in Montreal, Canada on June 19-23, 2005 Paper No. IPST05 -067

This circuit has a strong non-linear behavior in a stationary...