CN110094965B

CN110094965B - Novel direct-current smelting electric furnace

Info

Publication number: CN110094965B
Application number: CN201910100472.7A
Authority: CN
Inventors: 于文
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-02-11
Filing date: 2019-01-31
Publication date: 2024-04-02
Anticipated expiration: 2039-01-31
Also published as: CN110094965A; CN209844851U

Abstract

The invention provides a novel direct-current smelting electric furnace, which relates to the technical field of electric arc furnaces and comprises the following components: the rectification control circuit, the rectification power supply device, the short net device, the multi-load layout device including a plurality of electrodes, the electric furnace body, the rectification power supply device includes at least two double-circuit direct current power supply groups, four output terminals of each double-circuit direct current power supply group are respectively connected with three electrodes in the multi-load layout device through the short net device and form two current loops through the electric furnace molten pool load, each electrode in the multi-load layout device is connected with homopolar output terminals of the three-phase negative half-cycle rectification output circuit and the three-phase positive half-cycle rectification output circuit through the short net device, the rectification power supply device is provided with a plurality of output current loops, and the number of output current loops of the rectification power supply device is the same as that of the electrodes of the multi-load layout device. The defect that the load of the traditional multi-electrode direct current electric furnace technology is not matched with that of an electric furnace molten pool is overcome, and the practical industrial application value of smelting by using direct current is improved.

Description

Novel direct-current smelting electric furnace

The present application claims the priority of chinese patent application No. 201810139429.7 of chinese patent office, named "new dc smelting electric furnace", 11 of 2018, the entire content of which is incorporated herein by reference, while claims the priority of chinese patent application No. 201820241594.9 of chinese patent office, named "new dc smelting electric furnace", 11 of 2018, the entire content of which is incorporated herein by reference, while claims the priority of chinese patent application No. 201810411134.0 of chinese patent office, named "new dc smelting electric furnace", 02 of 2018, the entire content of which is incorporated herein by reference, while claims the priority of chinese patent application No. 201820643027.6 of chinese patent office, named "new dc smelting electric furnace", 02 of 2018, the entire content of which is incorporated herein by reference.

Technical Field

The invention relates to the technical field of arc furnaces, in particular to a novel direct-current smelting electric furnace.

Background

At present, the electric smelting furnaces at home and abroad basically adopt an alternating current power supply technology, the electric smelting furnaces adopting the alternating current power supply technology all adopt alternating current power supply with power frequency of 50 Hz-60 Hz, and because the electric smelting furnaces are characterized by low voltage and large current load, the eddy current loss of ferromagnetic parts around the electric furnace short net is large, the large current alternating current electric energy is difficult to be input into an electric furnace molten pool because of inductance factor of a conductive circuit of the electric furnace short net, the power factor of the whole system of the alternating current electric furnace is low because of the inductance factor of the conductive circuit of the electric furnace short net and the coexistence of the large current working condition and the inductance factor of the conductive circuit of the electric furnace short net, electrode arcs of the alternating current electric furnaces are ignited and extinguished 100-120 times per second, the arc combustion is unstable, and the defects of large electrode breakage consumption, high production ton and ore production consumption and high electricity consumption and the like in production are caused.

The number of the electric furnaces adopting the direct current power supply technology is small, the direct current electric furnaces adopting the direct current power supply technology basically need to adopt the bottom electrode technology, and the bottom electrode is difficult to be widely popularized and applied in the smelting industry due to easy burning loss.

In recent years, enterprises in China try to build and use a multi-electrode direct-current electric furnace system, basically, the problem of load matching between a direct-current power supply device and an electric furnace molten pool cannot be solved, and finally, power distribution in the electric furnace molten pool is uneven, smelting indexes in production practice are not ideal, and the advantages of direct-current electric energy large-current transmission cannot be fully exerted, so that practical industrial application value is brought to smelting work.

Disclosure of Invention

In view of the above, the invention aims to provide a novel direct-current smelting electric furnace, which can increase the number of molten pool load current loops between electrodes and ensure that electric power in a molten pool of the electric furnace is uniformly distributed, thereby matching the characteristics of a direct-current power supply device with the load characteristics of the molten pool of the electric furnace and improving the actual industrial operation value of smelting by using direct current.

In a first aspect, an embodiment of the present invention provides a novel direct current smelting electric furnace, including: the device comprises a rectification control circuit, a rectification power supply device, a short-net device, a multi-load layout device comprising a plurality of electrodes and an electric furnace body; the rectification control circuit is connected with the rectification power supply device, the rectification power supply device is connected with the multi-load layout device through a short-net device, and the multi-load layout device is connected with a molten pool in the electric furnace body; the rectification control circuit is used for controlling the rectification power supply device to work; the rectifying power supply device is used for providing direct-current electric energy for the multi-load layout device; the short-net device is used for an electric connection circuit between the rectifying power supply device and the multi-load layout device; the multi-load layout device is used for generating arc heat and resistance heat in a molten pool of the electric furnace body after being electrified so as to enable the arc heat and the resistance heat to smelt furnace burden in the molten pool of the electric furnace body;

The rectification power supply device comprises at least two double-loop direct current power supply groups, each double-loop direct current power supply group comprises a three-phase negative half-cycle rectification output circuit and a three-phase positive half-cycle rectification output circuit, each three-phase negative half-cycle rectification output circuit comprises a first positive electrode output terminal and a first negative electrode output terminal, each three-phase positive half-cycle rectification output circuit comprises a second positive electrode output terminal and a second negative electrode output terminal, four output terminals of each double-loop direct current power supply group are respectively connected with three electrodes in a multi-load layout device of a plurality of electrodes through a short-net device to form two current loops through an electric furnace bath load, each electrode in the multi-load layout device is connected with two homopolar output terminals in the three-phase negative half-cycle rectification output circuit and the three-phase positive half-cycle rectification output circuit which are related with the current loops through the short-net device, and the number of output current flow back circuits of the rectification power supply device is the same as the number of the electrodes of the multi-load layout device.

With reference to the first aspect, an embodiment of the present invention provides a first possible implementation manner of the first aspect, where each dual-loop dc power supply group has two homopolar output terminals connected to one electrode of the multiple-load layout device in a collinear manner after passing through the short-net device, and the other two heteropolar output terminals of each dual-loop dc power supply group are connected to two adjacent heteropolar electrodes associated with current loops in the multiple-load layout device after passing through the short-net device.

With reference to the first aspect, the embodiment of the present invention provides a second possible implementation manner of the first aspect, where the three-phase positive half-cycle rectification output circuit outputs three pulse direct currents of a three-phase positive half-cycle rectification waveform, the three-phase negative half-cycle rectification output circuit outputs three pulse direct currents of a three-phase negative half-cycle rectification waveform, and an arc current between an electrode and a furnace burden of an electric furnace is six pulse direct currents, where an ac component phase difference of corresponding phases of the three-phase positive half-cycle rectification waveform and the three-phase negative half-cycle rectification waveform is 180 degrees.

With reference to the first aspect, an embodiment of the present invention provides a third possible implementation manner of the first aspect, wherein the total number of electrodes of the multi-load layout device is an even number greater than 2, the number of the dual-loop dc power supply groups is 50% of the total number of electrodes of the multi-load layout device, and the number of three-phase negative half-cycle rectifying output circuits in the rectifying power supply device, the number of three-phase positive half-cycle rectifying output circuits in the rectifying power supply device, and the number of 50% of the total number of electrodes of the multi-load layout device are the same.

With reference to the first aspect, the embodiment of the present invention provides a fourth possible implementation manner of the first aspect, wherein a plane layout of the plurality of electrodes of the multi-load layout device is triangular, square, rectangular or parallelogram, and distances between adjacent electrodes are equal.

With reference to the first aspect, an embodiment of the present invention provides a fifth possible implementation manner of the first aspect, where the short-net device includes a plurality of short-net groups, each short-net group includes two equivalent conductive wires, and an equivalent line inductance of the two equivalent conductive wires of the short-net group is further used as a balancing reactor output by a rectifying power supply device, and each output terminal of the rectifying power supply device is connected to one electrode through one equivalent conductive wire of one short-net group.

With reference to the first aspect, an embodiment of the present invention provides a sixth possible implementation manner of the first aspect, where the three-phase negative half-cycle rectification output circuit includes: the transformer comprises a first three-phase secondary winding and a first high-power rectifying component, wherein the first high-power rectifying component comprises three first uncontrollable rectifying diodes, the synonym ends of the first three-phase secondary winding of the transformer are respectively connected with anodes of the three first uncontrollable rectifying diodes, and cathodes of the three first uncontrollable rectifying diodes are connected in a collinear manner and then are connected with a first positive electrode output terminal; the same-name ends of the first three-phase secondary winding of the transformer are connected in a collinear manner and then connected with the first negative electrode output terminal;

The three-phase positive half cycle rectification output circuit comprises: the transformer second three-phase secondary winding and the second high-power rectifying component comprise three second uncontrollable rectifying diodes, the homonymous ends of the transformer second three-phase secondary winding are respectively connected with anodes of the three second uncontrollable rectifying diodes, and cathodes of the three second uncontrollable rectifying diodes are connected in a collinear manner and then are connected with the second positive electrode output terminal; and the different-name ends of the second three-phase secondary winding of the transformer are connected in a collinear manner and then connected with the second negative electrode output terminal.

With reference to the first aspect, an embodiment of the present invention provides a seventh possible implementation manner of the first aspect, where the three-phase negative half-cycle rectification output circuit includes: the transformer comprises a first three-phase secondary winding, a first high-power rectifying component and a first follow current diode, wherein the first high-power rectifying component comprises three first controllable rectifying thyristors, control poles of the three first controllable rectifying thyristors are connected with a rectifying control circuit, different-name ends of the first three-phase secondary winding of the transformer are respectively connected with anodes of the three first controllable rectifying thyristors, cathodes of the three first controllable rectifying thyristors are connected in a collinear manner and then connected with cathodes of the first follow current diode and a first positive electrode output terminal, and common-name ends of the first three-phase secondary winding of the transformer are connected in a collinear manner and then connected with anodes of the first follow current diode and a first negative electrode output terminal;

The three-phase positive half cycle rectification output circuit comprises: the transformer second three-phase secondary winding, the high-power rectification subassembly of second, second freewheel diode, the high-power rectification subassembly of second includes three second controllable rectification thyristors, the control pole of three second controllable rectification thyristors with rectification control circuit links to each other, the homonymous end of transformer second three-phase secondary winding respectively with the positive pole of three second controllable rectification thyristors links to each other, the negative pole collinearly of three second controllable rectification thyristors is connected back with the negative pole of second freewheel diode with the second positive pole output terminal links to each other, the heteronymous end collinearly of transformer second three-phase secondary winding link to each other with the positive pole of second freewheel diode with second negative pole output terminal.

The embodiment of the invention has the following beneficial effects that the defect that the alternating current power supply technology is used for the smelting electric furnace is avoided: the eddy current loss of ferromagnetic parts of the electric furnace can be reduced, the skin effect of a conductive circuit is small, the overcurrent capacity of the electrode is enhanced, electric energy can be easily input into a molten pool of the electric furnace, the natural power factor of the electric furnace operation is high, the electrode arc is stable, the consumption is low and the like; the defects in the existing direct current power supply technology with the bottom electrode are avoided: the invention does not need a bottom electrode, can avoid the defect that the bottom electrode is easy to burn, is easy to popularize and use and reduces the use cost; the defect that the power supply device of the existing multi-electrode direct current electric furnace technology is not matched with the load of an electric furnace molten pool is overcome: the invention designs the rectification power supply device to reduce the problem of overlarge power consumption, reasonably increases the number of the molten pool load current loops between the electrodes of the smelting electric furnace, ensures that the electric power in the electric furnace molten pool is uniformly distributed, finally ensures that the output characteristic of the rectification power supply device is matched with the load characteristic of the electric furnace molten pool, and improves the practical industrial operation value of smelting by using direct current.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

In order to make the above objects, features and advantages of the present invention more comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a structural diagram of a novel direct current smelting electric furnace provided by an embodiment of the invention;

fig. 2a is a block diagram of a first dual-loop dc power supply unit according to an embodiment of the present invention;

fig. 2b is a schematic circuit diagram of a first dual-loop dc power supply unit according to an embodiment of the present invention;

FIG. 3 is a plan layout structure diagram of 4 electrodes according to an embodiment of the present invention;

FIG. 4 is a plan layout structure diagram of 6 electrodes according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of another layout of 6 electrodes according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a further planar layout of 6 electrodes according to an embodiment of the present invention;

FIG. 7 is a plan layout view of 8 electrodes according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of another layout of 8 electrodes according to an embodiment of the present invention;

FIG. 9a is a diagram of a three-phase positive half-cycle rectification waveform of a 3-pulse DC power provided by an embodiment of the present invention;

FIG. 9b is a diagram of a three-phase negative half-cycle rectification waveform of a 3-pulse DC power provided by an embodiment of the present invention;

FIG. 9c is a waveform diagram of a 6-pulse DC power provided by an embodiment of the present invention;

FIG. 10 is a block diagram of a novel direct current smelting electric furnace provided by an embodiment of the invention, which is provided with 4 electrodes;

FIG. 11 is a schematic diagram of an equivalent circuit with 4 electrodes of the novel direct current smelting electric furnace provided by the embodiment of the invention;

FIG. 12 is a block diagram of a novel DC smelting electric furnace with 6 electrodes provided by an embodiment of the invention;

FIG. 13 is another structure diagram of the novel direct current smelting electric furnace provided by the embodiment of the invention, which is provided with 6 electrodes;

FIG. 14 is a schematic view of another embodiment of the present invention, showing a novel DC smelting electric furnace having 6 electrodes;

FIG. 15 is a schematic diagram of an equivalent circuit with 6 electrodes of the novel direct current smelting electric furnace provided by the embodiment of the invention;

FIG. 16 is a block diagram of a novel direct current smelting electric furnace provided by an embodiment of the invention, which is provided with 8 electrodes;

FIG. 17 is another structure diagram of the novel direct current smelting electric furnace provided by the embodiment of the invention, which is provided with 8 electrodes;

fig. 18 is an equivalent circuit schematic diagram of the novel direct-current smelting electric furnace provided by the embodiment of the invention, which is provided with 8 electrodes.

Reference numerals illustrate: 1-rectifying a power supply device; 2-a short network device; 3-multiple load layout means; 4-an electric furnace body; 5-a rectification control circuit; 6-a three-phase primary side group of the transformer; 1-a first dual-loop dc power pack; 1-2-a second dual-loop dc power pack; 1-3-third double-loop DC power supply group; 1-4-fourth double-loop DC power supply group.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

For the convenience of understanding the embodiment, the novel direct current smelting electric furnace disclosed by the embodiment of the invention is firstly described in detail,

referring to fig. 1, fig. 2a, fig. 10, fig. 12, fig. 13, fig. 14, fig. 16, and fig. 17, an embodiment of the present invention provides a novel direct current smelting electric furnace, including: the electric furnace comprises a rectification control circuit 5, a rectification power supply device 1, a multi-load layout device 3 comprising a plurality of electrodes, a short-net device 2 and an electric furnace body 4, wherein the rectification control circuit 5 is connected with the rectification power supply device 1, the rectification power supply device is connected with the multi-load layout device 3 through the short-net device 2, and the multi-load layout device 3 is connected with a molten pool in the electric furnace body; the rectification control circuit 5 is used for controlling the rectification power supply device 1 to work; the rectifying power supply device 1 is used for providing direct-current electric energy for the multi-load layout device 3; the short-net device 2 is used for rectifying the electric connection lines of the power supply device 1 and the multi-load layout device 3; the multi-load arrangement device 3 is used for generating arc heat and resistance heat in an electric furnace molten pool after being electrified so as to enable the arc heat and the resistance heat to smelt furnace burden in the electric furnace molten pool.

The rectifying power supply device 1 comprises at least two double-loop direct current power supply groups, such as a first double-loop direct current power supply group 1-1, a second double-loop direct current power supply group 1-2, a third double-loop direct current power supply group 1-3 and a fourth double-loop direct current power supply group 1-4 shown in fig. 2a, 10, 12, 13, 14, 16 and 17, wherein the four double-loop direct current power supply groups are identical in construction principle, each double-loop direct current power supply group comprises a three-phase negative half-cycle rectifying output circuit and a three-phase positive half-cycle rectifying output circuit, each three-phase negative half-cycle rectifying output circuit comprises a first positive electrode output terminal and a first negative electrode output terminal, each three-phase positive half-cycle rectifying output circuit comprises a second positive electrode output terminal and a second negative electrode output terminal, each double-loop direct current power supply group is provided with four output terminals, the four output terminals of each double-loop direct current power supply group are respectively connected with three load layout devices 3 of a plurality of electrodes through a short network device 2, each three load layout device is connected with the three load layout devices of the three-phase negative half-cycle rectifying devices 1 through the same number of the positive electrode rectifying devices and the three-phase half-cycle rectifying output devices, and the three-phase rectifying devices are connected with the three-phase power supply device 1 through the positive electrode half-cycle rectifying devices through the positive electrode rectifying devices and the load device.

Wherein, each double-loop DC power supply group has two homopolar output terminals which are connected with one electrode in the multi-load layout device 3 through the short-net device 2 in a collinear way, and the other two heteropolar output terminals of each double-loop DC power supply group are connected with the adjacent other two heteropolar electrodes which are associated with the current loop in the multi-load layout device 3 through the short-net device 2. For example, each dual-loop dc power supply group has two positive polarity output terminals connected to one positive polarity electrode of the multi-load arrangement device 3 in a line through the short-net device 2, and the other two negative polarity output terminals of each dual-loop dc power supply group are connected to the adjacent other two negative polarity electrodes associated with the current loop in the multi-load arrangement device 3 through the short-net device 2. Or each double-loop direct current power supply group is provided with two negative polarity output terminals which are connected with one negative polarity electrode in the multi-load layout device 3 in a collinear way after passing through the short-net device 2, and the other two positive polarity output terminals of each double-loop direct current power supply group are connected with the adjacent other two positive polarity electrodes which are associated with current loops in the multi-load layout device 3 after passing through the short-net device 2.

For example, when the total number of the electrodes is four, the rectifying power supply device 1 adopts two double-loop direct current power supply groups to supply power; four output terminals of each double-loop direct current power supply group are respectively connected with three electrodes of the multi-load layout device 3 through the short net device 2, and two current loops are formed through electric furnace molten pool loads; each electrode in the multi-load layout device 3 is connected with a three-phase negative half-cycle rectification output circuit and a three-phase positive half-cycle rectification output circuit which are associated with current loops through a short-net device 2, and four paths of power outputs of the rectification power supply device 1 form four current loops through electric furnace molten pool loads among the four electrodes, and each current loop is three pulse direct current; the current value of each electrode is the combined value of the current values of two current loops flowing through the electrode, and the current flowing through each electrode is six-pulse direct current.

For example, the three-phase positive half-cycle rectification output circuit outputs 3-pulse direct current of a three-phase positive half-cycle rectification waveform, wherein the three-phase positive half-cycle rectification waveform of the 3-pulse direct current is as shown in fig. 9 a; the three-phase negative half-cycle rectification output circuit outputs 3-pulse direct current with a three-phase negative half-cycle rectification waveform, wherein the three-phase negative half-cycle rectification waveform of the 3-pulse direct current is shown in fig. 9 b; the current flowing through the electrode is 6 pulse dc, wherein the waveform of the 6 pulse dc is shown in fig. 9 c; the phase difference of the alternating current components of the corresponding phases of the three-phase positive half-cycle rectification waveform and the three-phase negative half-cycle rectification waveform is 180 degrees. From the above, the electrode arc of the invention has the harmonic degree of 6 pulse DC which is more gentle than the harmonic degree of 3 pulse, thereby improving the utilization rate of electric energy.

In some embodiments, the total number of electrodes of the multi-load layout device 3 is an even number greater than 2, and the number of the dual-loop dc power supply groups is half of the total number of electrodes of the multi-load layout device 3. For example, when the total number of the plurality of electrodes in the multi-load layout device is four and the number of the double-loop direct current power supply groups is two, the specific connection structure and the circuit working principle of the novel direct current smelting electric furnace are shown in fig. 10 to 11. When the total number of the electrodes in the multi-load layout device 3 is six and the number of the double-loop direct current power supply groups is three, the specific connection structure and the circuit working principle of the novel direct current smelting electric furnace are shown in fig. 12-15. When the total number of the electrodes in the multi-load layout device 3 is eight and the number of the double-loop direct current power supply groups is four, the specific connection structure and the circuit working principle of the novel direct current smelting electric furnace are shown in fig. 16-18. The number of current loops of the three-phase positive half-cycle rectification output circuits in the rectification power supply device 1, the number of current loops of the three-phase negative half-cycle rectification output circuits in the rectification power supply device 1, and 50% of the total number of electrodes of the multi-load layout device 3 can be made the same.

As shown in fig. 3 to 8, the distances between adjacent electrodes are equal, and the planar layout of the electrodes of the multi-load layout device 3 is triangular, rectangular or parallelogram. For example, when the total number of electrodes is 4, in fig. 3, the planar layout of the 4 electrodes is square, and each electrode is disposed at four corners of the square. When the total number of the electrodes is 6, the planar layout of the 6 electrodes may be shaped like a triangle of fig. 4, and as shown in connection with fig. 4, the triangle composed of the 6 electrodes may be composed of 4 small equilateral triangles, and the 6 electrodes are distributed at the corners of the 4 small equilateral triangles; or a rectangle as shown in fig. 5, and in combination with fig. 5, the rectangle composed of 6 electrodes may be composed of 4 small right triangles, and the 6 electrodes are distributed on each corner of the 4 small right triangles; or the parallelogram of figure 6, combined with the parallelogram of figure 6, the 6 electrodes can be composed of 4 small equilateral triangles, which is different from the arrangement mode of the 4 small equilateral triangles in figure 4, so as to obtain the parallelogram of figure 6. When the total number of the electrodes is 8, the planar layout of the 8 electrodes may be shaped like a rectangle of fig. 7, and as shown in connection with fig. 7, the rectangle composed of the 8 electrodes may be composed of 6 small right triangles, and the 8 electrodes are distributed at the corners of the 6 small right triangles, similar to fig. 5; or may be shaped as a parallelogram of fig. 8, and a parallelogram of 8 electrodes may be formed of 6 small equilateral triangles with 8 electrodes distributed over the corners of the 6 small equilateral triangles, similar to that of fig. 6.

The specific circuit structure of each dual-loop dc power supply unit in the rectifying power supply unit 1 of the novel dc smelting electric furnace may have two cases, where the first case is applicable to the situation that the load of the novel dc smelting electric furnace is reduced by using electric flashovers, and as shown in fig. 2b, the rectifying components in the first high-power rectifying component and the second high-power rectifying component in each dual-loop dc power supply unit are replaced by uncontrollable rectifying diodes, and the first freewheeling diode 1-1-1-3 and the second freewheeling diode 1-1-2-3 are not installed in each dual-loop dc power supply unit, and the three-phase negative half-cycle rectifying output circuit 1-1-1 includes: the transformer first three-phase secondary winding 1-1-1 and the first high-power rectifying component 1-1-1-2, wherein the first high-power rectifying component 1-1-1-2 comprises three first uncontrollable rectifying diodes, the synonym ends of the transformer first three-phase secondary winding 1-1-1 are respectively connected with anodes of the three first uncontrollable rectifying diodes, and cathodes of the three first uncontrollable rectifying diodes are connected in a collinear manner and then are connected with the first positive output terminal 1-1-1-5; the same-name ends of the first three-phase secondary winding 1-1-1 of the transformer are connected in a collinear way and then connected with the first negative electrode output terminal 1-1-1-4. The three-phase positive half cycle rectification output circuit 1-1-2 comprises: the transformer second three-phase secondary winding 1-1-2-1 and the second high-power rectifying component 1-1-2-2, wherein the second high-power rectifying component 1-1-2-2 comprises three second uncontrollable rectifying diodes, the homonymous ends of the transformer second three-phase secondary winding 1-1-2-1 are respectively connected with anodes of the three second uncontrollable rectifying diodes, and cathodes of the three second uncontrollable rectifying diodes are connected in a collinear manner and then are connected with the second positive output end 1-1-2-5; the different name ends of the second three-phase secondary winding 1-1-2-1 of the transformer are connected in a collinear way and then connected with the second negative electrode output terminal 1-1-2-4.

Referring to fig. 2b, in a case where the load electric flash of the novel dc electric smelting furnace is increased, the three-phase negative half-cycle rectification output circuit 1-1-1 includes: the transformer first three-phase secondary winding 1-1-1, the first high-power rectifying component 1-1-1-2 and the first follow current diode 1-1-3, wherein the first high-power rectifying component comprises three first controllable rectifying thyristors which are connected with a rectifying control circuit 5 (the connecting terminals of the three first controllable rectifying thyristors and the rectifying control circuit 5 are shown in fig. 2 b), the synonym ends of the transformer first three-phase secondary winding 1-1-1-1 are respectively connected with the anodes of the three first controllable rectifying thyristors, and the cathodes of the three first controllable rectifying thyristors are connected with the cathodes of the first follow current diode 1-1-1-3 and the first positive electrode output terminal 1-1-1-5 after being collinearly connected; the same-name ends of the first three-phase secondary winding 1-1-1 of the transformer are connected in a collinear way and then connected with the anode of the first freewheeling diode 1-1-1-3 and the first negative output terminal 1-1-1-4. The three-phase positive half cycle rectification output circuit 1-1-2 comprises: the transformer second three-phase secondary winding 1-1-2-1, the second high-power rectifying component 1-1-2-2 and the second follow current diode 1-1-2-3, wherein the second high-power rectifying component 1-1-2-2 comprises three second controllable rectifying thyristors, the three second controllable rectifying thyristors are connected with a rectifying control circuit 5 (the connecting terminals of the three second controllable rectifying thyristors and the rectifying control circuit 5 are shown in fig. 2 b), the homonymous ends of the transformer second three-phase secondary winding 1-1-2-1 are respectively connected with the anodes of the three second controllable rectifying thyristors, and the cathodes of the three second controllable rectifying thyristors are connected with the cathodes of the second follow current diode 1-1-2-3 and the second positive electrode output terminals 1-1-2-5 after being collinearly connected; the different name ends of the second three-phase secondary winding 1-1-2-1 of the transformer are connected in a collinear way and then connected with the anode of the second freewheeling diode 1-1-2-3 and the second negative output terminal 1-1-2-4. The double-loop direct current power supply group 1-1 comprises a transformer three-phase primary side group 6, a three-phase negative half-cycle rectification output circuit 1-1 and a three-phase positive half-cycle rectification output circuit 1-1-2. The first freewheeling diode 1-1-3 provides a freewheeling circuit for the load line induced current when the three-phase negative half-cycle rectification output circuit 1-1-1 is not fully loaded, prevents the load line induced current from flowing back to the first three-phase secondary winding 1-1-1 of the transformer, thereby reducing the power factor of an electrical system, and the second freewheeling diode 1-1-2-3 provides a freewheeling circuit for the load line induced current when the three-phase positive half-cycle rectification output circuit 1-1-2 is not fully loaded, prevents the load line induced current from flowing back to the second three-phase secondary winding 1-1-2-1 of the transformer, thereby reducing the power factor of the electrical system.

Through the structure, each rectifying component in the first high-power rectifying component 1-1-1-2 and the second high-power rectifying component 1-1-2-2 only bears 1/6 of electrode current of the novel direct-current smelting electric furnace, the number of the rectifying components is 1/2 of that of the three-phase bridge rectifying device in the prior art, the total power consumption of the rectifying components is 1/2 of that of the three-phase bridge rectifying device in the prior art, and the invention can be seen to reduce the self power consumption of the three-phase bridge rectifying device in the prior art and improve the electricity utilization efficiency of the smelting electric furnace.

The two cases of the three-phase positive half-cycle rectification output circuit and the three-phase negative half-cycle rectification output circuit are mainly distinguished in that the controllable rectification thyristor of the first case can be replaced by an uncontrollable rectification diode, at the moment, the uncontrollable rectification diode is not connected with a rectification control circuit, and meanwhile, a freewheeling diode is not required to be installed.

The short net device 2 comprises a plurality of short net groups, each short net group is respectively represented by 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-7 and 2-8, each short net group comprises 2 equivalent conductive wires, the inductive reactance of each 2 equivalent conductive wires is used as a balance reactor by an output circuit of the rectifying power supply device 1, and each output terminal of the rectifying power supply device 1 is connected with one electrode through 1 conductive wire in one short net device 2.

In actual work, referring to fig. 2b, 11, 15 and 18, each dual-loop dc power supply set further includes a three-phase primary side set 6 of a transformer, and after the three-phase primary side set 6 of the transformer is electrified, three-phase ac power with electromagnetic mutual inductance is provided to the three-phase negative half-cycle rectifying output circuit and the three-phase positive half-cycle rectifying output circuit through a ferromagnetic core of the transformer.

To sum up, the novel direct-current smelting electric furnace is described in detail by taking the following three examples:

in example 1, as shown in fig. 10 to 11, when the total number of the electrodes of the multi-load layout device 3 is four, the number of the double-loop dc power supply groups is two, the two double-loop dc power supply groups can be represented by using a first double-loop dc power supply group 1-1 and a second double-loop dc power supply group 1-2, the first double-loop dc power supply group 1-1 includes a three-phase negative half-cycle rectification output circuit 1-1-1 and a three-phase positive half-cycle rectification output circuit 1-1-2, the second double-loop dc power supply group 1-2 includes a three-phase negative half-cycle rectification output circuit 1-2-1 and a three-phase positive half-cycle rectification output circuit 1-2, and the 4 electrodes are represented by an electrode No. 1-1, an electrode No. 2, an electrode No. 3-3, an electrode No. 3 No. 4, an electrode No. 3-1 and an electrode No. 3-3 are positive polarity electrodes, an electrode No. 2 and an electrode No. 3-4 are negative polarity electrodes, and an electrode No. 3-1-1 and an electrode No. 2 and an electrode No. 3-4 are adjacent electrode No. 3-2 and an electrode 3-4 are respectively. For the first double-loop direct current power supply group 1-1, the positive output terminal of the three-phase negative half-cycle rectification output circuit 1-1-1 and the positive output terminal of the three-phase positive half-cycle rectification output circuit 1-1-2 are connected with the electrode 3-1, the negative output terminal of the three-phase negative half-cycle rectification output circuit 1-1 is connected with the electrode 3-4 No. 4, and the negative output terminal of the three-phase positive half-cycle rectification output circuit 1-1-2 is connected with the electrode 3-2 No. 2. For the second double-loop direct current power supply group 1-2, the positive output terminal of the three-phase negative half-cycle rectification output circuit 1-2-1 and the positive output terminal of the three-phase positive half-cycle rectification output circuit 1-2-2 are connected with the electrode 3-3, the negative output terminal of the three-phase negative half-cycle rectification output circuit 1-2-1 is connected with the electrode 3-2, and the negative output terminal of the three-phase positive half-cycle rectification output circuit 1-2-2 is connected with the electrode 3-4.

The negative electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-1-1 is connected with the electrode 3-4 of the No. 4 through the short net 1 group 2-1, the positive electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-1-1 is connected with the electrode 3-1 of the No. 1 through the short net 1 group 2-1, and the three-phase negative half-cycle rectification output circuit 1-1 forms a current loop i1 through an electrode molten pool operation resistance load between the short net 1 group 2-1 and the electrode 3-1 of the No. 1 and the electrode 3-4 of the No. 4.

The negative electrode output terminal of the three-phase positive half-cycle rectification output circuit 1-1-2 is connected with the electrode No. 2 3-2 through the short net 2 group 2-2, the positive electrode output terminal of the three-phase positive half-cycle rectification output circuit 1-1-2 is connected with the electrode No. 1-1 through the short net 2 group 2-2, and the three-phase positive half-cycle rectification output circuit 1-1-2 forms a current loop i2 through an electrode molten pool operation resistance load between the short net 2 group 2-2 and the electrode No. 1 electrode 3-1 and the electrode No. 2 electrode 3-2.

The negative electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-2-1 is connected with the electrode No. 2 3-2 through the short net 3 group 2-3, the positive electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-2-1 is connected with the electrode No. 3-3 through the short net 3 group 2-3, and the three-phase negative half-cycle rectification output circuit 1-2-1 forms a current loop i3 through an electrode molten pool operation resistance load between the short net 3 group 2-3 and the electrode No. 2 electrode 3-2 and the electrode No. 3-3.

The negative electrode output terminal of the three-phase positive half-cycle rectification output circuit 1-2-2 is connected with the electrode 3-4 of the No. 4 through the short net 4 group 2-4, the positive electrode output terminal of the three-phase positive half-cycle rectification output circuit 1-2-2 is connected with the electrode 3-3 of the No. 3 through the short net 4 group 2-4, and the three-phase positive half-cycle rectification output circuit 1-2-2 forms a current loop i4 through an electrode molten pool operation resistance load between the electrode 3-3 of the short net 4 group 2-4 and the electrode 3-3 of the No. 3 and the electrode 3-4.

The 6 pulse DC current required by the No. 1 electrode 3-1 electric arc is synthesized by a current loop i1 and a current loop i 2; the 6 pulse DC current required by the No. 2 electrode 3-2 electric arc is synthesized by a current loop i2 and a current loop i 3; the 6 pulse DC current required by the electrode 3-3 arc is synthesized by a current loop i3 and a current loop i 4; the 6 pulse DC current required by the No. 4 electrode 3-4 arc is synthesized by a current loop i4 and a current loop i 1.

The waveform of the current loop i1 and the current of the current loop i3 is a three-phase negative half-cycle rectification waveform; the waveform of the current loop i2 and the current of the current loop i4 is three-phase positive half-cycle rectification waveform; the angle joint load of the electric furnace molten pool is 3 pulse DC, and the phase difference of the alternating current components of the corresponding phases of the three-phase positive half-cycle rectification waveform and the three-phase negative half-cycle rectification waveform is 180 degrees; the current waveform of each electrode arc is 6 pulse DC, and the phase difference of the alternating current components of the corresponding phases is 180 degrees.

Example 2, as shown in connection with fig. 12 to 15, when the total number of electrodes of the multi-load layout apparatus 3 is 6, the number of the double-loop dc power supply groups is 3, and the three double-loop dc power supply groups may be represented by using a first double-loop dc power supply group 1-1, a second double-loop dc power supply group 1-2, and a third double-loop dc power supply group 1-3, the first double-loop dc power supply group 1-1 including a three-phase negative half-cycle rectification output circuit 1-1-1 and a three-phase positive half-cycle rectification output circuit 1-1-2, the second double-loop dc power supply group 1-2 including a three-phase negative half-cycle rectification output circuit 1-2-1 and a three-phase positive half-cycle rectification output circuit 1-2-2, the third double-circuit direct current power supply group 1-3 comprises a three-phase negative half-cycle rectification output circuit 1-3-1 and a three-phase positive half-cycle rectification output circuit 1-3-2, wherein the number 1 electrode 3-1, the number 2 electrode 3-2, the number 3 electrode 3-3, the number 4 electrode 3-4, the number 5 electrode 3-5 and the number 6 electrode 3-6 are respectively adopted for representing the number 1 electrode 3-1, the number 3 electrode 3-3 and the number 5 electrode 3-5 as positive polarity electrodes, the number 2 electrode 3-2 and the number 4 electrode 3-4 as well as the number 6 electrode 3-6 as negative polarity electrodes, the number 1 electrode 3-1 is adjacent to the number 2 electrode 3-2 and the number 6 electrode 3-6, the number 3 electrode 3-3 is adjacent to the number 2 electrode 3-2 and the number 4 electrode 3-4, electrode number 5, 3-5, is adjacent to electrode number 4, 3-4, and electrode number 6, 3-6. For the first double-loop direct current power supply group 1-1, the positive output terminal of the three-phase negative half-cycle rectification output circuit 1-1-1 and the positive output terminal of the three-phase positive half-cycle rectification output circuit 1-1-2 are connected with the electrode No. 1-1, the negative output terminal of the three-phase negative half-cycle rectification output circuit 1-1 is connected with the electrode No. 6-3, and the negative output terminal of the three-phase positive half-cycle rectification output circuit 1-1-2 is connected with the electrode No. 2-3. For the second double-loop direct current power supply group 1-2, the positive output terminal of the three-phase negative half-cycle rectification output circuit 1-2-1 and the positive output terminal of the three-phase positive half-cycle rectification output circuit 1-2-2 are connected with the electrode 3-3, the negative output terminal of the three-phase negative half-cycle rectification output circuit 1-2-1 is connected with the electrode 3-2, and the negative output terminal of the three-phase positive half-cycle rectification output circuit 1-2-2 is connected with the electrode 3-4. For the third double-loop direct current power supply group 1-3, the positive output terminal of the three-phase negative half-cycle rectification output circuit 1-3-1 and the positive output terminal of the three-phase positive half-cycle rectification output circuit 1-3-2 are connected with the electrode No. 5 3-5, the negative output terminal of the three-phase negative half-cycle rectification output circuit 1-3-1 is connected with the electrode No. 4 3-4, and the negative output terminal of the three-phase positive half-cycle rectification output circuit 1-3-2 is connected with the electrode No. 6 3-6.

The negative electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-1-1 is connected with the electrode 3-6 of the No. 6 through the short net 1 group 2-1, the positive electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-1-1 is connected with the electrode 3-1 of the No. 1 through the short net 1 group 2-1, and the three-phase negative half-cycle rectification output circuit 1-1 forms a current loop i1 through an electrode molten pool operation resistance load between the short net 1 group 2-1 and the electrode 3-1 of the No. 1 and the electrode 3-6 of the No. 6.

The negative electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-2-1 is connected with the electrode No. 2 3-2 through the short net 3 group 2-3, the positive electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-2-1 is connected with the electrode No. 3-3 through the short net 3 group 2-3, and the three-phase negative half-cycle rectification output circuit 1-2-1 forms a current loop i3 through an electrode molten pool operation resistance load between the short net 3 group 2-3 and the electrode No. 2 electrode 3-2 and between the electrode No. 3-3 and the electrode No. 3 electrode 3-3.

The negative electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-3-1 is connected with the electrode 3-4 of the electrode 4 through the short net 5 group 2-5, the positive electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-3-1 is connected with the electrode 3-5 of the electrode 5 through the short net 5 group 2-5, and the three-phase negative half-cycle rectification output circuit 1-3-1 forms a current loop i5 through an electrode molten pool operation resistance load between the electrode 3-4 of the electrode 4 and the electrode 3-5 of the short net 5 group 2-5.

The negative electrode output terminal of the three-phase positive half-cycle rectification output circuit 1-3-2 is connected with the electrode 3-6 of No. 6 through the short net 6 group 2-6, the positive electrode output terminal of the three-phase positive half-cycle rectification output circuit 1-3-2 is connected with the electrode 3-5 of No. 5 through the short net 6 group 2-6, and the three-phase positive half-cycle rectification output circuit 1-3-2 forms a current loop i6 through an electrode molten pool operation resistance load between the electrode 3-5 of the short net 6 group 2-6 and the electrode 3-5 of No. 5 and the electrode 3-6 of No. 6.

The 6 pulse current required by the No. 1 electrode 3-1 electric arc is synthesized by a current loop i1 and a current loop i 2; the 6 pulse current required by the No. 2 electrode 3-2 electric arc is synthesized by a current loop i2 and a current loop i 3; the 6 pulse current required by the electrode 3-3 arc is synthesized by a current loop i3 and a current loop i 4; the 6 pulse current required by the No. 4 electrode 3-4 electric arc is synthesized by a current loop i4 and a current loop i 5; the 6 pulse current required by the No. 5 electrode 3-5 electric arc is synthesized by a current loop i5 and a current loop i 6; the 6 pulse current required by the No. 6 electrode 3-6 arc is synthesized by a current loop i6 and a current loop i 1.

A current loop i1, a current loop i3 and a current loop i5, wherein the current waveform of the current loop i5 is a three-phase negative half-cycle rectification waveform; the current loop i2, the current loop i4 and the current loop i6 have three-phase positive half-cycle rectification waveforms; the angle joint load of the electric furnace molten pool is 3 pulse DC, and the phase difference of the alternating current components of the corresponding phases of the three-phase positive half-cycle rectification waveform and the three-phase negative half-cycle rectification waveform is 180 degrees; the current waveform of each electrode arc is 6 pulse DC, and the phase difference of the alternating current components of the corresponding phases is 180 degrees.

In example 3, as shown in fig. 16 to 18, when the total number of the electrodes of the multi-load layout device 3 is 8, the number of the double-loop dc power supply sets is 4, the 4 double-loop dc power supply sets may be represented by using the first double-loop dc power supply set 1-1, the second double-loop dc power supply set 1-2, the third double-loop dc power supply set 1-3, and the fourth double-loop dc power supply set 1-4, and the 8 electrodes are represented by using the electrode 1, the electrode 2, the electrode 3-3, the electrode 4, the electrode 3-4, the electrode 5, the electrode 3-5, the electrode 6, the electrode 3-7, and the electrode 8, wherein the electrode 1, the electrode 3-3, the electrode 5, the electrode 3-7 are positive polarity electrodes, the electrode 2, the electrode 3-4, the electrode 3-6, the electrode 8 is negative polarity electrodes, and the adjacent electrode 1, electrode 3-1, 2, electrode 3-2, and electrode 8, and adjacent electrode 3-7, and electrode 3-8 are adjacent to electrode 3, and electrode 3-8, and adjacent electrode 3-8, 3-8, and electrode 3-8. For the first double-loop direct current power supply group 1-1, the positive output terminal of the three-phase negative half-cycle rectification output circuit 1-1-1 and the positive output terminal of the three-phase positive half-cycle rectification output circuit 1-1-2 are connected with the electrode No. 1-1, the negative output terminal of the three-phase negative half-cycle rectification output circuit 1-1 is connected with the electrode No. 8-3, and the negative output terminal of the three-phase positive half-cycle rectification output circuit 1-1-2 is connected with the electrode No. 2-3. For the second double-loop direct current power supply group 1-2, the positive output terminal of the three-phase negative half-cycle rectification output circuit 1-2-1 and the positive output terminal of the three-phase positive half-cycle rectification output circuit 1-2-2 are connected with the electrode 3-3, the negative output terminal of the three-phase negative half-cycle rectification output circuit 1-2-1 is connected with the electrode 3-2, and the negative output terminal of the three-phase positive half-cycle rectification output circuit 1-2-2 is connected with the electrode 3-4. For the third double-loop direct current power supply group 1-3, the positive output terminal of the three-phase negative half-cycle rectification output circuit 1-3-1 and the positive output terminal of the three-phase positive half-cycle rectification output circuit 1-3-2 are connected with the electrode No. 5 3-5, the negative output terminal of the three-phase negative half-cycle rectification output circuit 1-3-1 is connected with the electrode No. 4 3-4, and the negative output terminal of the three-phase positive half-cycle rectification output circuit 1-3-2 is connected with the electrode No. 6 3-6. For the fourth double-loop direct current power supply group 1-4, the positive output terminal of the three-phase negative half-cycle rectification output circuit 1-4-1 and the positive output terminal of the three-phase positive half-cycle rectification output circuit 1-4-2 are connected with the electrode No. 7 3-7, the negative output terminal of the three-phase negative half-cycle rectification output circuit 1-4-1 is connected with the electrode No. 6 3-6, and the negative output terminal of the three-phase positive half-cycle rectification output circuit 1-4-2 is connected with the electrode No. 8 3-8.

The negative electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-1-1 is connected with the electrode 3-8 of the No. 8 through the short net 1 group 2-1, the positive electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-1-1 is connected with the electrode 3-1 of the No. 1 through the short net 1 group 2-1, and the three-phase negative half-cycle rectification output circuit 1-1 forms a current loop i1 through an electrode molten pool operation resistance load between the short net 1 group 2-1 and the electrode 3-1 of the No. 1 and the electrode 3-8 of the No. 8.

The negative electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-4-1 is connected with the electrode 3-6 of the No. 6 through the short net 7 group 2-7, the positive electrode output terminal of the three-phase negative half-cycle rectification output circuit 1-4-1 is connected with the electrode 3-7 of the No. 7 through the short net 7 group 2-7, and the three-phase negative half-cycle rectification output circuit 1-4-1 forms a current loop i7 through an electrode molten pool operation resistance load between the short net 7 group 2-7 and the electrode 3-6 of the No. 6 and the electrode 3-7 of the No. 7.

The negative electrode output terminal of the three-phase positive half-cycle rectification output circuit 1-4-2 is connected with the electrode 3-8 of the No. 8 through the short net 8 group 2-8, the positive electrode output terminal of the three-phase positive half-cycle rectification output circuit 1-4-2 is connected with the electrode 3-7 of the No. 7 through the short net 8 group 2-8, and the three-phase positive half-cycle rectification output circuit 1-4-2 forms a current loop i8 through an electrode molten pool operation resistance load between the electrode 3-7 of the short net 8 group 2-8 and the electrode 3-7 of the No. 7 and the electrode 3-7 of the No. 8.

The 6 pulse DC current required by the No. 1 electrode 3-1 electric arc is synthesized by a current loop i1 and a current loop i 2; the 6 pulse DC current required by the No. 2 electrode 3-2 electric arc is synthesized by a current loop i2 and a current loop i 3; the 6 pulse DC current required by the electrode 3-3 arc is synthesized by a current loop i3 and a current loop i 4; the 6 pulse DC current required by the No. 4 electrode 3-4 electric arc is synthesized by a current loop i4 and a current loop i 5; the 6 pulse direct current required by the No. 5 electrode 3-5 electric arc is synthesized by a current loop i5 and a current loop i 6; the 6 pulse direct current required by the No. 6 electrode 3-6 electric arc is synthesized by a current loop i6 and a current loop i 7; the 6 pulse DC current required by the No. 7 electrode 3-7 electric arc is synthesized by a current loop i7 and a current loop i 8; the 6 pulse DC current required by the No. 8 electrode 3-8 arc is synthesized by a current loop i8 and a current loop i 1.

The current waveform of the current loop i1, the current loop i3 and the current loop i5 and the current waveform of the current loop i7 are three-phase negative half-cycle rectification waveforms; the current waveform of the current loop i2, the current loop i4 and the current loop i6 and the current waveform of the current loop i8 is three-phase positive half-cycle rectification waveform; the angle joint load of the electric furnace molten pool is 3 pulse DC, and the phase difference of the alternating current components of the corresponding phases of the three-phase positive half-cycle rectification waveform and the three-phase negative half-cycle rectification waveform is 180 degrees; the current waveform of each electrode arc is 6 pulse DC, and the phase difference of the alternating current components of the corresponding phases is 180 degrees.

The relative steps, numerical expressions and numerical values of the components and steps set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise.

Any particular values in all examples shown and described herein are to be construed as merely illustrative and not a limitation, and thus other examples of exemplary embodiments may have different values.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In addition, in the description of embodiments of the present invention, unless explicitly stated and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," "fourth," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Finally, it should be noted that: the above examples are only specific embodiments of the present invention, and are not intended to limit the scope of the present invention, but it should be understood by those skilled in the art that the present invention is not limited thereto, and that the present invention is described in detail with reference to the foregoing examples: any person skilled in the art may modify or easily conceive of the technical solution described in the foregoing embodiments, or perform equivalent substitution of some of the technical features, while remaining within the technical scope of the present disclosure; such modifications, changes or substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention, and are intended to be included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A direct current smelting electric furnace, characterized by comprising: the electric furnace comprises a rectification control circuit (5), a rectification power supply device (1), a short-net device (2), a multi-load layout device (3) comprising a plurality of electrodes and an electric furnace body (4); the rectification control circuit (5) is connected with the rectification power supply device (1), the rectification power supply device (1) is connected with the multi-load layout device (3) through the short-net device (2), and the multi-load layout device (3) is connected with a molten pool in the electric furnace body (4); the rectification control circuit (5) is used for controlling the rectification power supply device (1) to work; the rectifying power supply device (1) is used for providing direct-current electric energy for the multi-load layout device (3); the short-net device is used for an electric connection circuit between the rectifying power supply device and the multi-load layout device; the multi-load layout device (3) is used for generating arc heat and resistance heat in a molten pool of the electric furnace body (4) after being electrified so as to enable the arc heat and the resistance heat to smelt furnace burden in the molten pool of the electric furnace body (4);

the rectification power supply device (1) comprises at least two double-loop direct current power supply groups, each double-loop direct current power supply group comprises a three-phase negative half-cycle rectification output circuit and a three-phase positive half-cycle rectification output circuit, the three-phase negative half-cycle rectification output circuit comprises a first positive electrode output terminal and a first negative electrode output terminal, the three-phase positive half-cycle rectification output circuit comprises a second positive electrode output terminal and a second negative electrode output terminal, four output terminals of each double-loop direct current power supply group are respectively connected with three electrodes in the multi-load distribution device (3) through a short-net device (2) to form two current loops through an electric furnace molten pool load, each electrode in the multi-load distribution device (3) is connected with two homopolar output terminals in the three-phase negative half-cycle rectification output circuit and the three-phase positive half-cycle rectification output circuit which are related to the current loops through the short-net device (2), and the number of output current loops of the rectification power supply device (1) is the same as that of the electrodes of the multi-load distribution device (3).

2. The direct-current smelting electric furnace according to claim 1, wherein each double-circuit direct-current power supply group is provided with two homopolar output terminals which are connected with one electrode in the multi-load layout device (3) in a collinear way after passing through the short-net device (2), and the other two heteropolar output terminals of each double-circuit direct-current power supply group are connected with the adjacent other two heteropolar electrodes which are associated with the current loop in the multi-load layout device (3) after passing through the short-net device (2).

3. The direct current smelting electric furnace according to claim 2, wherein the three-phase positive half-cycle rectification output circuit outputs three pulse direct current of a three-phase positive half-cycle rectification waveform, the three-phase negative half-cycle rectification output circuit outputs three pulse direct current of a three-phase negative half-cycle rectification waveform, and the arc current between the electrode and the furnace charge of the electric furnace is six pulse direct current, wherein the alternating current components of corresponding phases of the three-phase positive half-cycle rectification waveform and the three-phase negative half-cycle rectification waveform are 180 degrees out of phase.

4. The direct-current smelting electric furnace according to claim 1, characterized in that the total number of electrodes of the multi-load layout device (3) is an even number greater than 2, the number of the double-loop direct-current power supply groups is 50% of the total number of electrodes of the multi-load layout device (3), and the number of three-phase negative half-cycle rectifying output circuits in the rectifying power supply device (1), the number of three-phase positive half-cycle rectifying output circuits in the rectifying power supply device (1), and 50% of the total number of electrodes of the multi-load layout device (3) are the same.

5. A direct current smelting electric furnace according to claim 4, characterized in that the planar layout of the plurality of electrodes of the multi-load layout device (3) is triangular or square or rectangular or parallelogram, and the distances between adjacent electrodes are equal.

6. A direct current smelting electric furnace according to claim 1, characterized in that the short-net device (2) comprises a plurality of short-net groups, each short-net group comprises two equivalent conductive wires, the equivalent line inductance of the two equivalent conductive wires of the short-net group is also used as a balancing reactor for the output of the rectifying power supply device (1), and each output terminal of the rectifying power supply device (1) is connected with one electrode through one equivalent conductive wire of one short-net group in the short-net device (2).

7. The direct current smelting electric furnace according to claim 1, wherein the three-phase negative half-cycle rectification output circuit includes: the transformer comprises a first three-phase secondary winding and a first high-power rectifying component, wherein the first high-power rectifying component comprises three first uncontrollable rectifying diodes, the synonym ends of the first three-phase secondary winding of the transformer are respectively connected with anodes of the three first uncontrollable rectifying diodes, cathodes of the three first uncontrollable rectifying diodes are connected in a collinear manner and then connected with a first positive electrode output terminal, and the synonym ends of the first three-phase secondary winding of the transformer are connected in a collinear manner and then connected with a first negative electrode output terminal;

The three-phase positive half cycle rectification output circuit comprises: the transformer second three-phase secondary winding and the second high-power rectifying component, the second high-power rectifying component comprises three second uncontrollable rectifying diodes, the homonymous ends of the transformer second three-phase secondary winding are respectively connected with anodes of the three second uncontrollable rectifying diodes, cathodes of the three second uncontrollable rectifying diodes are connected in a collinear manner and then connected with the second positive electrode output terminal, and the homonymous ends of the transformer second three-phase secondary winding are connected in a collinear manner and then connected with the second negative electrode output terminal.

8. The direct current smelting electric furnace according to claim 1, wherein the three-phase negative half-cycle rectification output circuit includes: the transformer comprises a first three-phase secondary winding, a first high-power rectifying component and a first follow current diode, wherein the first high-power rectifying component comprises three first controllable rectifying thyristors, control poles of the three first controllable rectifying thyristors are connected with a rectifying control circuit (5), the synonym ends of the first three-phase secondary winding of the transformer are respectively connected with anodes of the three first controllable rectifying thyristors, cathodes of the three first controllable rectifying thyristors are connected in a collinear way and then connected with cathodes of the first follow current diode and a first positive electrode output terminal, and the synonym ends of the first three-phase secondary winding of the transformer are connected in a collinear way and then connected with anodes of the first follow current diode and a first negative electrode output terminal;

The three-phase positive half cycle rectification output circuit comprises: the transformer second three-phase secondary winding, the high-power rectification subassembly of second, second freewheel diode, the high-power rectification subassembly of second includes three second controllable rectification thyristors, the control pole of three second controllable rectification thyristors with rectification control circuit (5) link to each other, the homonymous end of transformer second three-phase secondary winding respectively with the positive pole of three second controllable rectification thyristors links to each other, the negative pole collinearly of three second controllable rectification thyristors is connected the back with the negative pole of second freewheel diode with the second positive pole output terminal links to each other, the heteronymous end collinearly of transformer second three-phase secondary winding is connected the back with the positive pole of second freewheel diode with second negative pole output terminal links to each other.