Reactive Power Compensation System for Alloy Smelting Electric Furnace System

Abstract

The invention provides a reactive power compensation system of an alloy smelting electric furnace system. The reactive power compensation system comprises a power supply grid, an electric furnace transformer, an electrode, and electric furnace, a first compensation device, a second compensation device, and a reactive power flow controller, wherein the electric furnace transformer is connected with the power supply grid through a power transmission line; one end of the electrode is connected with the electric furnace transformer; the other end of the electrode is arranged in the electric furnace so as to supply power to metal to be smelted in the electric furnace; the first compensation device is connected with the electric furnace transformer so as to compensate reactive power produced by the electric furnace transformer; the second compensation device is arranged between the electric furnace transformer and the electrode so as to compensate reactive power produced by a short network and the electrode; and the reactive power flow controller is used for controlling the reactive power compensation dosage of the first compensation device according to input power and output power of the electric furnace transformer and controlling the reactive power compensation dosage of the second compensation device according to the magnitude of reactance during full-load operation of the electric furnace. According to the embodiment of the invention, the reactive power compensation system has the advantages of reducing the reactive consumption of the short network effectively, increasing three-phase power balance, reducing energy consumption and increasing smelting speed.

Description

technical field [0001] The invention relates to the technical field of alloy smelting, in particular to a reactive power compensation system for an electric furnace system for manganese-based ferroalloy (silicon, carbon-manganese) smelting. Background technique [0002] The alloy smelting electric furnace system, such as the manganese submerged heat electric furnace system, can be equivalent to an inductive load under the condition of full load. The overall composition of the system is composed of transmission lines, transformers, short networks, electrodes and other devices. The analysis of the structural characteristics and working characteristics of the large-scale submerged arc furnace shows that 70% of the reactance of the large-scale submerged arc furnace system (alloy smelting electric furnace system) is generated by the short network system, and 30% of the reactance is generated by transformers, transmission lines, etc. The short network is a high current working sys...

AI Technical Summary

Problems solved by technology

The analysis of the structural characteristics and working characteristics of the large-scale submerged arc furnace shows that 70% of the reactance of the large-scale submerged arc furnace system (alloy smelting electric furnace system) is generated by the short network system, and 30% of the reactance is generated by transformers, transmission lines, etc. The short network is a high current working system, the maximum current can reach 60,000-70,000 amperes, so the performance of the short network determines the performance of the submerged arc furnace. It is for this reason that the natural power factor of the system is difficult The natural power factor of most large-scale electric furnaces is below 0.7. The lower power factor not only reduces the efficiency of the transformer, but also consumes a lot of reactive power. The power imbalance between the phases increases, and the highest degree of imbalance can reach more than 20%, which leads to low smelting efficiency and increased power consumption

[0003] In order to improve the natural power factor of the system, the traditional method is to perform reactive power compensation at the high-voltage end, but the compensation at the high-voltage end cannot solve the problem of three-phase balance, and because the inductive reactance of the short network accounts for more than 70% of the inductive reactance of the entire system , so the compensation at the high-voltage end does not achieve the purpose of reducing the inductance of the short-circuit system, improving the power factor of the short-circuit system, and increasing the output of the transformer

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