SU1555923A1 - Device for controlling electric conditions of multislag multiphase ore-smelting electric furnace - Google Patents

Abstract

The invention relates to electrical engineering. The purpose of the invention is to increase the productivity of the furnace by increasing the accuracy of maintaining a rational mode. The rational mode is characterized by minimal negative differential resistance of the first phase. The parameters of the dynamic foil-ampere characteristic (DWA) of the first phase, quantitatively reflecting its area through the magnitude of the reactive power, from sensor 5 enter the phase balancing unit 2 of the furnace, and from block 6 dividing the amplitude values of current by voltage, reflecting the angle of inclination of the axis DWA first phase to the axis of the currents, in the first optimizer 9 of the first phase. For the rational characteristic obtained, an electric signal is formed in the division unit 6 by changing at a fixed value the electrode depth through the second optimizer 10 of the voltage level of the regulator 8 so that the magnitude of the signal from the amplitude current value dividing unit 6 corresponds to the angle of the DIA axis current axis equal to 45 degrees. The characteristics of the first phase are compared in block 2 phase balancing with the corresponding signals of other phases, depending on the magnitude and mismatch sign, the electrodes of the other phases are moved in the direction of its decrease. 2 Il.

Description

The invention relates to electrothermal, and more specifically to devices for controlling the electrical mode of the electric recovery furnaces (RVP) .5

The purpose of the invention is to increase the productivity of the furnace by increasing the efficiency of maintaining a rational mode.

FIG. 1 shows the functional heme device; in fig. 2 - dynamic current-voltage characteristics (DVA) of one phase of the furnace.15

The device for controlling the electric mode of the furnace 1 comprises a phase balancing unit 2 of the furnace, in each from the first to the i-th phase of the furnace a voltage sensor 3 and a current sensor, a sensor 5 20 of reactive phase power, a dividing unit 6, an electrode displacement regulator 7, a regulator The torus 8 switches the transformer voltage levels, the first 9 and second 10 optimizers. The first 25 output of the first optimizer 9 of each phase is connected to the first of two for this phase of the furnace, the input of the phase balancing unit 2 of the furnace, the second output to the input of the controller 7 for moving the electrode, the third output to the first input of the second optimizer 10, the second input of which is connected with the first output of the current sensor 4, and the output with the input of the switching regulator 8 of the voltage levels of the transformer of this phase.

The first output of the phase reactive power sensor 5 is connected to the second of the two for the given phase of the furnace, the input block of Q2 2 furnace phase balancing, the second output to the first input of the first optimizer 9 the first input of the dividing unit 6 is connected to the output of the voltage sensor 3 of this phase The second input is 4c with the second output of current sensor 4. The output of dividing unit 6 is connected to the second input of the first optimizer 9. In each of the furnace phases, besides the first, the first and second optimizers each have one correction input, and the correction input of the first optimizer 9 is connected to the first of two for this phase of the furnace output of the balancing unit 2 furnace phases, and the corrective input of the second optimizer 10 - with the second output of the furnace phase balancing unit, the second of the two for the given furnace phase.

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The operation of the proposed device is as follows.

The phase phase and the voltage of the first phase of the furnace 1 are measured using sensors 3 and k. Using the sensor 5, the reactive power is used to generate an electrical signal proportional to the area of the DIRECTIONS of the first phase (characteristic A, Fig. 2). The electrode of the first phase is moved in the direction of decreasing the area TWICE. In this case, the electrode is raised to a level corresponding to characteristic B (Fig. 2) with a rational mode of the first phase of the furnace 1. It is advisable to move the electrode only in the range of operating currents up to 1M к, ks and operating voltages up to Phase 1, controlled by sensors 3 and k current and voltage. Further elevation of the electrode leads to an increase in the area of TWEAK and, accordingly, to an increase in the reactive power measured by the sensor 5 due to an increase in the negative differential resistance of the electric circuit. In addition, the phase current is reduced, which is outside the operating range.

The first optimizer 9 of the first phase performs the role of a comparison unit with memory with an effect on the actuator of the electrode displacement controller 7. When the minimum of the electrical signal from the sensor 5 of reactive power (Fig. 2, characteristic B) is reached, the depth of the electrode of this phase is fixed. This minimum corresponds to the lowest possible loss in the furnace in the first Laz.

The parameters of the TWA of the first phase, quantitatively reflecting its area through the magnitude of the reactive power, from sensor 5 enter the furnace phase balancing unit 2, and from the unit 6 dividing the amplitude current values by voltage, reflecting the angle of inclination of the axis of the DVA of the first phase to the axis of currents - into the first optimizer 9 of the first phase. In order to obtain a rational characteristic B (Fig. 2), an electrical signal is formed in dividing unit 6, changing at a fixed electrode depth through the second optimizer 10, the voltage level of regulator 8 so that the magnitude of the signal from dividing current amplitude values by voltage matched

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the angle of the RPA axis to the current axis,

equal to 5 °.

The characteristics of the first phase are compared in the phase balancing unit with the corresponding signals of the other phases from the second to the i-th. Depending on the magnitude and sign of the mismatch, the electrodes of the other phases are moved in the direction of its reduction (mismatch). When the current exceeds a phase of a predetermined operating range, the voltage regulator 8 is affected in the direction of decreasing the current error.

The use of the device allows to increase the productivity of the furnace by increasing the accuracy of stabilization of its rational mode of operation with a decrease in power consumption.

Claims (1)

Invention Formula A device for controlling the electrical mode of a multi-slag multi-25 two for a given phase block input the second output is with the first input of the second optimizer, the second input of which is connected to the first output of the current sensor, and the output to the input of the switching of the voltage steps of the phase formatter, in each phase except the first, the first and second optics are provided with a corrective input the input of the first optimizer is connected to the first of two for a given phase of the furnace output of the furnace phase balancing unit, and the correction input of the second optimizer is connected to the second output of the furnace phase symmetrization unit of the second furnace phase of the furnace two, characterized in that , in order to increase the productivity of the furnace by increasing the accuracy of maintaining a rational mode, it additionally contains each phase of the furnace a dividing unit and a reactive power generator of the phase, the first output of which is connected to the second and a phase ore reduction electric furnace containing a furnace phase balancing unit, in each furnace phase a voltage sensor, a current sensor, the first optimizer, the first output of which is connected to the first of the furnace phase balancing two for the furnace phase, the second output to the controller input electrode movement, tre30 balancing the phases of the furnace, the second in turn - with the first input of the first optimizer, the first input of the dividing unit of each phase is connected to the output of a voltage sensor of this phase, the second input is connected to the second output of the sensor, the output of the dividing unit is connected to the second input of the first optimizer of this phase . 0 0 five 5 two for this phase block input 6 This output is connected to the first input of the second optimizer, the second input of which is connected to the first output of the current sensor, and the output to the input of the switching regulator of the voltage stages of the phase transformer, in each phase of the furnace, except for the first, the first and second optimizers are equipped with a correction input the corrective input of the first optimizer is connected to the first of two for the given furnace phase output of the phase balancing unit of the furnace, and the correcting input of the second optimizer is connected to the second output of the phase balancing unit of the second for the given phase of the furnace echi, characterized in that, in order to increase productivity by increasing the furnace to maintain the accuracy management mode, it further comprises in each phase furnace dividing unit and the sensor phase reactive power, which first output is connected to the second of 0 balancing the phases of the furnace, the second output - with the first input of the first optimizer, the first input of the dividing unit of each phase is connected to the output of a voltage sensor of this phase, the second input is connected to the second output of the current sensor, the output of the dividing unit is connected to the second input of the first optimizer of this phase. Figg