Method for measuring electrode current through electrode current measuring device for low voltage compensation of submerged arc furnace

Abstract

The invention provides a method for measuring electrode current through an electrode current measuring device for low voltage compensation of a submerged arc furnace. The method for measuring the electrode current comprises the following steps that a Rogowski coil output signal is a differential voltage signal of primary current; a first summing integrator performs vector summing integration on the signal to obtain capacitance compensation current; a second summing integrator performs vector summing integration on the signal to obtain furnace transformation low-voltage-side current; the capacitance compensation current and the furnace transformation low-voltage-side current are sent to a first adder and subjected to vector subtraction calculation to obtain compensated current on a short net behind a low voltage compensation access point; the compensated current is sent to a second adder; and front-phase compensated current is sent to the current-phase second adder, and is subtracted from the current-phase compensated current to obtain current-phase electrode current. The method has the characteristics of accurate measurement, wide measurement range, convenience for installation and simple structure.

Description

technical field [0001] The invention relates to large current measurement in the field of metallurgical industry, in particular to a method for measuring electrode current through an electrode current measuring device used for low pressure compensation of a submerged arc furnace. Background technique [0002] The submerged arc furnace is an industrial electric furnace that consumes a lot of power. The current of the low-voltage side of the furnace transformer (also known as the submerged arc furnace transformer) is mostly tens of thousands or even hundreds of thousands of amperes. The side current transformer samples, and then converts the electrode current, such as figure 1 Shown, CT A , CT B , CT C It is a current transformer set on the high-voltage side, which detects the line current on the high-voltage side Then convert the electrode current according to the gear ratio of the furnace transformer Due to the influence of the iron loss and copper loss of the transfo...

AI Technical Summary

Problems solved by technology

[0006] At present, almost all electrode current parameters adopt the method of converting the high-voltage side current. Although this method is simple and convenient, due to the influence of the iron loss and copper loss of the transformer, and the impedance and inductance of the low-voltage short network, the converted electrode current It cannot faithfully reflect the real electrode current situation. Due to the participation of the compensation current when there is low-voltage reactive power compensation, this method cannot obtain the electrode current correctly. Therefore, this type of current sampling method seriously affects the rationality of the electrode operation.

Images