Study Of Generation Mechanism And Suppression Strategies Of Harmonic In Arc Furnace

In recent years,for the arc furnace steel-making technology in the economic advantages of industrial production,the use of AC arc furnace has been increasing on Industrial production.Its capacity of a single-phase is bigger and bigger.The interference of arc furnace of power supply system has become even more prominent,and therefore,its harmonic control technology is urgent need.Taking into account the inadequacy of the existing arc furnace model,a hybrid modeling method is presented by modulating the steady and dynamic model.Modulation of the arc radius using sine wave signal,Gauss random signal and low frequency chaotic signal,the dynamic model was established.By comparing simulation results with the measured data and the corresponding waveform,we can fully verify the reasonableness of the new hybrid modeling and it can provide a basis for the study of the back arc furnace harmonic governance.Two types of arc furnace control measures are proposed.On the one hand,the traditional method of passive management is used,On the other hand is to add reactive compensation equipment in the power system of arc furnace,through differential power compensator real-time compensation,to reduce or even eliminate arc furnace load voltage fluctuation and unbalanced three-phase,inhibit arc furnace harmonics from the source.In view of the contradiction between the performance and system stability under the traditional control strategy of voltage source filter has not been solved,the advantages and disadvantages of two conventional voltage source control strategies were compared.On this baisis,the paper focus on studing a voltage-source compound control strategy,and designed a complete circuit structure of the compound control strategy.On the active suppression strategies,arc furnace produced serious power quality problem in the process of smelting,which has the characteristics of large harmonic content,three-phase imbalance,continuous voltage fluctuation and flicker.This paper first analyses the classification of the reactive power compensation device,through the compensation of simulation analysis and performance between reactive power devices,SVG+ scheme is put forward.On the basis of the theoretical analysis,arc furnace power grid model and the comprehensive compensation system model are set up.Through analysis of the system reactive power,power factor and power grid current voltage waveform before and after comprehensive compensation system put in the power system of arc furnace,fully verified the rationality and feasibility of the proposed control scheme.