36MVA manganese-silicon alloy fully-closed submerged arc direct current submerged arc furnace

Abstract

The invention discloses a 36MVA manganese-silicon alloy fully-closed submerged arc direct-current submerged arc furnace. The submerged arc furnace comprises a direct-current furnace body and at least two groups of voltage transformation and rectification devices electrically connected with the direct-current furnace body, the direct current furnace body is provided with an electrode holder matched with the output end of the voltage transformation and rectification device, the electrode holder is provided with an electrode, and the output end of the voltage transformation and rectification device is connected with the electrode. The direct current furnace body is sealed through a furnace cover so that the furnace face can not burn, the temperature in the furnace is at least 4000 DEG C when the direct current furnace body works, a plurality of through holes are formed in the furnace cover, the electrodes penetrate through the through holes, the electrodes are self-baking electrodes, the rated direct current output by the voltage transformation rectifying device is at least 70000 A, and the rated direct current output by the voltage transformation rectifying device is at least 260 V. Through sealing design combination of the self-baking electrode and the furnace cover, the oxidation loss of the electrode is reduced, the oxygen content of the furnace surface is reduced, and CO combustion in the furnace is inhibited.

Description

Technical Field

[0001] The invention belongs to the field of ore-fired furnaces, and in particular relates to a 36MVA manganese-silicon alloy fully enclosed submerged arc DC ore-fired furnace. Background Art

[0002] Submerged arc furnace is a vital production equipment in the ferroalloy industry, and plays an irreplaceable role in smelting ferroalloy products such as silicon manganese, ferrosilicon, ferrochrome, and nickel. In the early days, submerged arc furnaces mainly used three-phase power supply from the power grid after transformer step-down for smelting. Most of them were small-capacity and open-type. Limited by the technical level at that time, the traditional submerged arc furnace power supply method caused many problems in actual use, including three-phase imbalance, low power factor, and the resulting harmonic pollution, high smelting energy consumption, and high noise. With the application of DC technology, these problems have been effectively solved, which not only balances the three-phase current and improves the power factor, but also significantly improves the operating efficiency and energy efficiency of submerged arc furnaces, and has made great progress in energy conservation, emission reduction, and product quality stability.

[0003] However, the carbon thermal reduction reaction of manganese silicon alloy is an extremely complex high-temperature smelting process, which involves multiphase flow transfer between ore, slag, manganese silicon alloy and furnace gas, as well as multi-physical field coupling between electromagnetic field, temperature field, flow field and metal oxide components. For large-scale high-power DC furnaces, it is currently impossible to achieve good stability and controllability. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides a 36MVA manganese silicon alloy fully enclosed submerged arc DC ore-fired furnace. The technical problem to be solved by the present invention is achieved through the following technical solutions: A 36MVA manganese silicon alloy fully enclosed submerged arc DC ore-fired furnace, comprising: A DC furnace body and at least two sets of transformer and rectifier devices electrically connected to the DC furnace body; The DC furnace body is provided with an electrode holder that cooperates with the output end of the transformer and rectifier device. The electrode holder has an electrode. The output end of the transformer and rectifier device is connected to the electrode. The DC furnace body is sealed by a furnace cover to prevent the furnace surface from burning and the temperature in the furnace is at least 4000°C during operation. The furnace cover is provided with a plurality of through holes for the electrodes to pass through. The electrodes are self-baking electrodes. The rated DC current output by the transformer and rectifier device is at least 70000A, and the rated DC voltage output is at least 260V.

[0005] In a specific embodiment, the transformer and rectifier device includes: a transformer group, a first rectifier cabinet, and a second rectifier cabinet; The input end of the transformer group is connected to the power supply, and the output end is respectively connected to the first rectifier cabinet and the second rectifier cabinet, the first output end of the first rectifier cabinet and the first output end of the second rectifier cabinet are connected to the first electrode, and the second output end of the first rectifier cabinet and the second output end of the second rectifier cabinet are connected to the second electrode, wherein the first electrode and the second electrode have opposite polarities.

[0006] In a specific embodiment, the transformer group includes: a voltage regulating transformer, a first rectifier transformer, and a second rectifier transformer; the input end of the voltage regulating transformer is connected to the power supply, the output end of the voltage regulating transformer is connected to the first rectifier transformer and the second rectifier transformer, the first rectifier transformer is connected to the first rectifier cabinet, and the second rectifier transformer is connected to the second rectifier cabinet.

[0007] In a specific embodiment, the first rectifier cabinet and the second rectifier cabinet both include a rectifier circuit, and the number of thyristors on each rectifier arm of the rectifier circuit is determined according to the rated DC current and DC voltage output by the transformer-rectifier device.

[0008] In a specific embodiment, the rectifier circuit is a double reverse star rectifier circuit, and the thyristors arranged on the same rectifier arm have a preset forward volt-ampere characteristic curve.

[0009] In a specific implementation, the voltage regulating transformer comprises: an on-load voltage regulating switch, wherein the on-load voltage regulating switch has a gear position controller, and the gear position controller is used to control the output voltage of the voltage regulating transformer.

[0010] In a specific embodiment, it also includes a control signal generator, the control signal generator is connected to the matrix switch, and the matrix switch is respectively connected to a plurality of gear controllers, a main and standby controllers, a remote controller, and a current feedback controller; The matrix switch is used to receive a control signal with a preset coding rule to control the corresponding switch to be turned on or off according to the control signal with the preset coding rule, wherein the control signal with the preset coding rule includes: a signal type field, a linkage field, and a control adjustment field.

[0011] In a specific embodiment, at least a portion of the switch nodes of the matrix switch are further connected to a delay circuit, the output end of the at least a portion of the switch nodes is connected to a gear controller, and the control signal with a preset coding rule further includes a delay signal trigger field; The control signal generator is also used to set the signal type field to a field for controlling the gear controller and set the linkage field to a field for controlling the remote controller when it is determined that the thyristor control angle is less than a preset angle.

[0012] In a specific implementation, the matrix switch is further used to control the corresponding delay circuit to be enabled when it is determined that the delay signal trigger field in the control signal of the preset coding rule is not empty.

[0013] In a specific embodiment, a DC current sensor is provided at the output end of the transformer-rectifier device, and current transformers are provided at the input ends of the first rectifier transformer and the second rectifier transformer, and both the DC current sensor and the current transformer are connected to the control signal generator; The control signal generator is also used to set the signal type field to a field for controlling a current feedback controller and set the linkage field to a field for controlling a remote controller when it is determined that the feedback signal of the DC current sensor is lost or the feedback signal of the current transformer is lost.

[0014] Beneficial effects of the present invention: 1. The 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace of the present invention combines the self-baking electrode with the furnace cover sealing design to reduce electrode oxidation loss and reduce the oxygen content on the furnace surface to inhibit CO combustion in the furnace.

[0015] 2. The 36MVA manganese silicon alloy fully enclosed submerged arc DC electric arc furnace of the present invention can accurately control the opening or closing of the corresponding switches through the coordinated use of the control signal generator and the matrix switch, by receiving the control signal with the preset coding rules, so as to realize the stable control of the gear controller, the main and standby controller, the remote controller, the current feedback controller and other equipment, and realize the seamless connection control of the corresponding controller through the linkage field, thereby improving the controllability in the event of a fault.

[0016] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a block diagram of a 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace module provided by an embodiment of the present invention; Figure 2 This is a circuit diagram of a transformer and rectifier device for a 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace provided by an embodiment of the present invention; Figure 3 It is a schematic diagram of a transformer group of a 36MVA manganese silicon alloy fully enclosed submerged arc DC ore-fired furnace provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of switch control of a 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace provided in an embodiment of the present invention; Figure 5It is a schematic diagram of switch control of another 36MVA manganese silicon alloy fully enclosed submerged arc DC electric arc furnace provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0018] The present invention is further described in detail below with reference to specific embodiments, but the embodiments of the present invention are not limited thereto. Example

[0019] See also Figure 1 , Figure 1 The present invention provides a 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace module block diagram, including: A DC furnace body 1 and at least two sets of transformer and rectifier devices 2 electrically connected to the DC furnace body 1; The DC furnace body 1 is provided with an electrode holder that cooperates with the output end of the transformer and rectifier device 2, and the electrode holder has an electrode 3. The output end of the transformer and rectifier device 2 is connected to the electrode 3. The DC furnace body 1 is sealed by a furnace cover to prevent combustion of the furnace surface and the temperature in the furnace is at least 4000°C during operation. The furnace cover is provided with a plurality of through holes for the electrodes to pass through. The electrode 3 is a self-baking electrode. The rated DC current output by the transformer and rectifier device is at least 70000A, and the rated DC voltage output is at least 260V.

[0020] It should be noted that the main structure of the 36MVA manganese silicon alloy fully enclosed submerged arc DC ore-fired furnace of this embodiment is designed and completed according to the size requirements. For example, the main structure is mainly divided into: furnace body, furnace cover, feeding system, electrode lifting and lowering pressure release, electrode holder, water cooling system, purification flue, emission flue, taphole exhaust, short net, hydraulic system, etc.

[0021] Specifically, the furnace body is a fixed quadrilateral structure, the furnace bottom is forced to ventilate and cool, and the furnace shell is 200mm higher than the working platform for sealing. The two tapping holes are arranged at 180° on both sides of the furnace body, and the I-beams at the bottom of the furnace are arranged in parallel by 40C I-beams. The furnace bottom is set with multiple temperature measurement points (electrode center and electric furnace center), and multiple temperature measuring thermocouples are used accordingly (2 at each point, one high and one low monitoring position). Three maintenance channels are made in the furnace bottom foundation to facilitate the maintenance and replacement of thermocouples. The temperature measuring thermocouple is selected as K couple, and the furnace bottom cooling with a temperature resistance of 1000°℃ adopts 8 mixed flow fans to ventilate and cool the furnace bottom from the side. The thickness of the furnace shell side plate is, for example, 25mm, the thickness of the furnace bottom plate is 30mm, and the thickness of the rib plate is 16mm.

[0022] There is a pneumatic ventilation butterfly valve (remote operation is possible, with manual zipper) behind each of the two tapping exhaust hoods. After the exhaust hoods are made, they are knotted with fire-resistant knots (or refractory fiber blocks are used). The exhaust hoods need to be insulated from the upper platform. The tapping exhaust hood covers 1 molten iron ladle and 3 slag ladles. The tapping exhaust pipe is one meter outside the plant (multiple furnaces can share one set of dust removal).

[0023] The furnace cover consists of an electrode cover plate, an outer cover plate, an electrode sealing guide device, an inspection furnace door, an observation door, an explosion-proof device, a pressure measuring device, a temperature measuring device, a hanging rod device, etc. The top cover plate and the side cover plate of the furnace cover are 90°; the electrode seals are made of 06Cr18Ni11Ti, and the other cover plates are made of carbon steel material Q235B. The electrode seal adopts a copper fan-shaped seal, and the copper fan-shaped sealing ring is made of H62; mica + ceramic fiber + glass ribbon is used as insulation between the cover plate and the material pipe, and refractory castables are used for sealing after the refractory bricks are positioned. 4 removable furnace doors are set at the electrode intervals, and 4 small doors are set. The furnace cover is equipped with explosion-proof holes, 2 pressure detection points, 16 material pipe holes, 4 electrode through holes, and 2 flue cover plates; there is a temperature measuring point in the center of the furnace cover, and 1 temperature measuring point is set in each of the two flues. Supply and welding of cover anchor hooks. The thickness of the bottom plate is 10mm, and the thickness of the outer waterproof plate and cover plate is 8mm.

[0024] The electrode holder is composed of copper tiles, copper pressure rings, water-cooled protection screens, conductive copper tubes, copper tile hangers, pressure ring hangers, lower holding tubes, water-cooled pipelines, insulation, etc.

[0025] The electrode holder adopts bellows pressure ring type. The pressure ring type electrode holder uses the bellows expansion tube to fill the pressure oil to realize the copper tile pressing the electrode, which can realize one-to-one radial tightening of the copper tile, so that the pressure between the copper tile and the electrode is uniform. The outer cooling jacket of the bellows is cooled by casting T2. There are 8 copper tiles and 8 bellows on each phase electrode. The copper tiles and conductive copper tubes are made of T2. The rated current density of the conductive copper tube is ≤3.0A / mm", and Φ75×15mm copper tubes are selected. The pressure ring is made of forged T2 copper-silver alloy. The water-cooling protection screen is made of 06Cr18NI11Ti The water-cooled structure is made of 8 pieces. Dense aluminum silicate ceramic fiber felt is filled between the water-cooled protection screen and the electrode. The main function of the electrode cooling water system is to deliver the external cooling water from the cooling water distributor to the parts that need to be cooled at the bottom of the electrode. The internal connecting hose of the gripper is a threaded hose, and the connection with the water distributor is connected with an insulating hose. The copper pressure ring of each phase is made of 8 pieces, and the upper protection screen of each phase is made of 8 pieces. The gripper circulating water pipe is made of Q235, the gripping tube at the conductive copper tube position is made of 06Cr19Ni10 material (500mm higher than the conductive copper tube position), the thickness of the lower gripping tube is 14mm, the water-cooled cable specification is 2800mm², the length is about 2.5 meters, and the current density is about 2.68A / mm² at the maximum current.

[0026] The 36MVA manganese silicon alloy fully enclosed submerged arc DC electric arc furnace of this embodiment combines the self-baking electrode with the furnace cover sealing design to reduce electrode oxidation loss, reduce the oxygen content on the furnace surface and inhibit CO combustion in the furnace.

[0027] In one specific embodiment, see Figure 2 , Figure 2 It is a circuit diagram of a transformer and rectifier device for a 36MVA manganese silicon alloy fully enclosed submerged arc DC electric furnace provided in an embodiment of the present invention. The input end of the transformer group 21 is connected to a power supply 20, and the output end is respectively connected to a first rectifier cabinet 22 and a second rectifier cabinet 23. The first output end of the first rectifier cabinet 22 and the first output end of the second rectifier cabinet 23 are connected to a first electrode 31, and the second output end of the first rectifier cabinet 22 and the second output end of the second rectifier cabinet 23 are connected to a second electrode 32, wherein the first electrode 31 and the second electrode 32 have opposite polarities.

[0028] In one specific embodiment, see Figure 3 , Figure 3 It is a schematic diagram of a transformer group of a 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace provided in an embodiment of the present invention. The transformer and rectifier device 2 includes: a transformer group 21, a first rectifier cabinet 22 and a second rectifier cabinet 23. The transformer group 21 includes: a voltage regulating transformer 211, a first rectifier transformer 212, and a second rectifier transformer 213; the input end of the voltage regulating transformer 211 is connected to the power supply 20, and the output end of the voltage regulating transformer 211 is connected to the first rectifier transformer 212 and the second rectifier transformer 213, the first rectifier transformer 212 is connected to the first rectifier cabinet 22, and the second rectifier transformer 213 is connected to the second rectifier cabinet 23.

[0029] In a specific embodiment, the first rectifier cabinet 22 and the second rectifier cabinet 23 both include a rectifier circuit, and the number of thyristors on each rectifier arm of the rectifier circuit is determined according to the rated DC current and DC voltage output by the transformer-rectifier device.

[0030] In a specific embodiment, the rectifier circuit is a double reverse star rectifier circuit, and the thyristors arranged on the same rectifier arm have a preset forward volt-ampere characteristic curve.

[0031] The voltage regulating transformer is a three-phase three-column iron core structure, and the rectifier transformer is a two-phase five-column iron core structure with full oblique joints; the iron core assembly is a multi-level step joint, no punching, and TENAX polyester tape binding pull plate structure. The iron core clamp has sufficient strength and good insulation. The iron core and the oil tank adopt an upper and lower double positioning structure, and the iron core is reliably grounded to the oil tank through the clamp. The iron core material is selected from high-quality cold-rolled oriented silicon steel sheet 30Q120, and the low magnetic density design makes the product have excellent no-load performance. Low loss performance. The coil is tightly wound, and the conductor is insulated at the transposition point. Several wire segments at the end of the coil are horizontally tied to improve the strength of the coil. The pad on the transformer coil is made of high-density cardboard, and the coil adopts kerosene vapor phase drying process. When assembling the body, an oil pressure jack is used to press the coil so that the coil pressing force reaches the specified value of the design. The coil adopts the structure of internal and external support bars and is firmly tied with heat shrink tape. The support bars and pads are arranged vertically and evenly. Auxiliary support bars are added to ensure the stability of the coil and improve the short-circuit resistance. The wire insulation is reinforced insulation, and the insulation assembly between windings uses a thin paper tube + small oil gap + molded hard angle ring structure to improve the insulation strength and mechanical strength.

[0032] The lead connection of the voltage regulating transformer adopts the cold pressing method; its advantages are: 1) There are no welding points inside the transformer, ensuring the neatness of the transformer body. 2) The processability is good, which can reduce the mechanical force caused by the vibration of the coil. 3) The current distribution from the transformer coil to the copper busbar is more uniform, reducing the circulation loss between the copper busbars.

[0033] The AC busbar wiring copper bar is led out from the middle and lower part of one side of the transformer in the long axis direction, with 12 pieces for each body. The DC busbar wiring copper bar is led out from the middle box cover in the long axis direction of the transformer, using a "single row or double row open structure". Large area anti-magnetic stainless steel plate is used at the outlet of the high current outlet terminal to isolate the magnetism and reduce eddy current loss.

[0034] A set of current transformers for measurement and protection is set on each phase of the output side of the voltage regulating transformer. The secondary current of the current transformer is 5A and the transformer accuracy is 0.5 level. The secondary side terminals of the current transformer are led out to the current transformer terminal box for external wiring.

[0035] The transformer oil tank adopts bell-shaped design and core-free structure. Anti-loosening measures are taken on the top and bottom of the body to ensure that the transformer is not displaced and the core is not lifted after it arrives at the site. A manhole is set near the load switch for easy installation and maintenance. Each transformer has no less than two manholes, and the transformer can be entered without a hanging cover. An oil sampling valve is set at the bottom of the oil tank, and a ladder is set on the transformer oil tank. The position of the ladder is convenient for taking gas samples and observing gas relays. A manhole is set at the load switch for on-site maintenance. The oil tank is mainly made of Q235.

[0036] There are sufficient number and strength of fulcrums, hanging points and traction points on the transformer oil tank, and a sufficiently large oil drain valve is provided at the bottom of the transformer oil tank. The transformer is equipped with a 90° track roller, and a traction device is provided at the bottom of the oil tank. The transformer oil conservator adopts a capsule structure, and the transformer oil is completely isolated from the air. The oil conservator is equipped with a pointer oil level gauge with electric contact output; it is equipped with an oil filling valve, a venting valve, a desiccant, a butterfly valve, etc. The desiccant is installed in a position that is easy to operate and replace silica gel. There is a special butterfly valve between the oil conservator and the oil tank for easy disassembly and assembly. Its volume ensures that the oil does not overflow under full load conditions when the ambient temperature is up to 40℃, and the oil conservator has enough oil when it is not put into operation at -15℃.

[0037] The transformer is equipped with a stainless steel control terminal box to collect the above protection signals. The control signal is connected to the terminal box by a cable. There is a gap between the signal terminal and the positive and negative terminals, and the control terminal has a spare capacity of more than 15%. The transformer inlet bushing adopts a pollution-proof bushing, which fully considers the environmental pollution of slight conductive dust in the air.

[0038] In a specific implementation, the voltage regulating transformer 211 includes: an on-load voltage regulating switch, wherein the on-load voltage regulating switch has a gear controller 4, and the gear controller is used to control the output voltage of the voltage regulating transformer.

[0039] In one specific embodiment, see Figure 4 , Figure 4 It is a switch control schematic diagram of a 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace provided by an embodiment of the present invention, and also includes a control signal generator 5, the control signal generator 5 is connected to the matrix switch 6, and the matrix switch 6 is respectively connected to a plurality of gear controllers 4, a main and standby controller 7, a remote controller 8, and a current feedback controller 9; The matrix switch 6 is used to receive a control signal with a preset coding rule to control the corresponding switch to be turned on or off according to the control signal with the preset coding rule, wherein the control signal with the preset coding rule includes: a signal type field, a linkage field, and a control adjustment field.

[0040] It should be noted that for the large manganese silicon alloy fully enclosed submerged arc DC ore-fired furnace of this embodiment, the workshop covers an area of ​​at least 20,000 square meters, and the distance between different devices is large, and even on different floors. In most control scenarios, different devices are generally required to be linked and controlled, rather than a single control of a node or a device. In non-emergency situations, the control time accuracy is generally required to be low. Remote control is used within the equipment delay and safety control time. However, in scenarios where the equipment fails or needs to be switched or shut down, the remote control method cannot be accurately controlled due to the high delay and the problem of too long trigger logic. Therefore, this embodiment is controlled by a matrix switch, and the controllable range of the switch matrix is ​​improved by setting the corresponding control field.

[0041] Specifically, the signal type field represents the specific device connected to the switch matrix. It should be noted that since the switch matrix may be connected to multiple devices of the same type, the signal type field also needs to be used to distinguish devices of the same type. The linkage field represents that after the current control device is completed, the next or next control devices associated with the control device are automatically controlled to achieve seamless control. The control adjustment field represents the specific control method, such as controlling which switch loop in the switch matrix is ​​opened or closed, thereby controlling the corresponding gear controllers, master and standby controllers, remote controllers, and current feedback controllers. It should be noted that the control devices connected to the switch matrix can be adjusted according to actual conditions, and are not limited to the above categories.

[0042] In a preferred scenario, when executing an action corresponding to a linkage field, the control signal generator is also used to generate a control signal with a preset coding rule for linkage execution according to the action corresponding to the linkage field. When the action corresponding to the linkage field is executed normally, the control signal with the preset coding rule for linkage execution is only stored and does not trigger the action. When the action corresponding to the linkage field is executed abnormally, the control signal with the preset coding rule for linkage execution is called to re-execute. That is to say, the control signal with the preset coding rule for linkage execution is not actually generated by an external input signal, but by an internal preset execution logic. Therefore, during the execution of the linkage field, if an external control signal is received, the external control signal is executed first. Accordingly, the control signal with the preset coding rule may also include a field for distinguishing between an external control signal and an internally generated signal, so that when the external control signal conflicts with the internally generated signal, the external control signal is executed first.

[0043] It should be noted that, since the linkage field may be associated with the next one or several next control devices, after each linkage execution is completed, the linkage field is adjusted accordingly to make the logical association before and after the linkage control consistent.

[0044] In one specific embodiment, see Figure 5 , Figure 5 1 is another switch control schematic diagram of a 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace provided in an embodiment of the present invention, wherein at least a portion of the switch nodes of the matrix switch 6 are also connected to a delay circuit 10, and the output end of the at least a portion of the switch nodes is connected to a gear controller 4, and the control signal with a preset coding rule also includes a delay signal trigger field; The control signal generator is also used to set the signal type field to a field for controlling the gear controller and set the linkage field to a field for controlling the remote controller when it is determined that the thyristor control angle is less than a preset angle.

[0045] In a specific implementation, the matrix switch is further used to control the corresponding delay circuit to be enabled when it is determined that the delay signal trigger field in the control signal of the preset coding rule is not empty.

[0046] In some scenarios where delayed triggering is required, although the delay instruction can be triggered by software control, such as delaying the trigger signal for 50 seconds, if there is a conflict in the execution of instructions under the condition of high controllability, the control may fail. In addition, since the matrix switch of this embodiment interconnects multiple controlled devices, the more complex the execution logic, the worse the controllability. Therefore, an additional delay circuit is used for delay control to avoid the influence of software logic disorder. The delay circuit of the present application can be set with an enable switch separately, which is turned on when it is needed. When a certain delay circuit is turned on, the next time the path where the delay switch is located receives a control signal, the delay circuit triggers the delay signal by itself. During the delay stage, even if the path still receives other types of control signals, it will not trigger the control until the delay time ends to respond to the control signal before the delay time.

[0047] In one example, when it is determined that the thyristor control angle is less than a preset angle (for example, the control angle is less than 0°), it indicates that there may be a voltage fault in the system. At this time, the signal type field is set to the field used to control the gear controller. Since the control angle is less than 0°, delay control is required during voltage regulation. The delay signal trigger field is used to control the delay circuit of the path where the gear controller is located to open, for example, a delay of 60 seconds. After the control action is completed, relevant technical personnel are required to conduct on-site troubleshooting or alarm troubleshooting. The linkage field is used to control the remote controller to shut down and no longer receive remote control instructions to avoid control conflicts. The remote control instruction refers to an instruction received by a control signal generator, such as a control instruction sent through a back-end control network or an instruction generated by a control signal generator.

[0048] In a specific embodiment, a DC current sensor is provided at the output end of the variable voltage rectifier device, and current transformers are provided at the input ends of the first rectifier transformer and the second rectifier transformer. The DC current sensor and the current transformers are both connected to the control signal generator; The control signal generator is further configured to, when it is determined that the feedback signal of the DC current sensor is lost or the feedback signal of the current transformer is lost, set the signal type field to a field for controlling the current feedback controller, and set the linkage field to a field for controlling the remote controller. In this embodiment, the feedback signal of the DC current sensor and the feedback signal of the current transformer are used as the basis for judging the magnitude of the output current fluctuation with each other as the main and backup. If a certain feedback signal is lost, it is necessary to switch and adjust through the field for controlling the current feedback controller. Similarly, if relevant technicians need to conduct on-site troubleshooting or alarm troubleshooting, the remote controller is controlled to close through the linkage field and no longer receive remote control instructions, so as to avoid control conflicts.

[0049] Through the combined use of the control signal generator and the matrix switch in this embodiment, by receiving control signals with a preset coding rule, the corresponding switches can be accurately controlled to be turned on or off, realizing stable control of devices such as the gear controller, the main and backup controllers, the remote controller, and the current feedback controller, and realizing seamless connection control of the corresponding controllers through the linkage field, thus improving the controllability in case of faults.

[0050] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0051] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal connection of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0053] Although the present application is described herein in conjunction with various embodiments, in the process of implementing the claimed application, those skilled in the art may understand and implement other variations of the disclosed embodiments by viewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "one" or "an" does not exclude multiple situations. A single processor or other unit may implement several functions listed in a claim. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0054] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace, characterized in that: include: A DC furnace body and at least two sets of transformer and rectifier devices electrically connected to the DC furnace body; The DC furnace body is provided with an electrode holder that matches the output end of the transformer and rectifier device, and the electrode holder has an electrode, and the output end of the transformer and rectifier device is connected to the electrode, wherein the DC furnace body is sealed by a furnace cover so that the furnace surface does not burn and the temperature in the furnace is at least 4000°C during operation, and the furnace cover is provided with a plurality of through holes for the electrodes to pass through, and the electrodes are self-baking electrodes, and the rated DC current output by the transformer and rectifier device is at least 70000A, and the rated DC voltage output is at least 260V; the transformer and rectifier device comprises: a transformer group, a first rectifier cabinet and a second rectifier cabinet; the transformer group comprises: a voltage regulating transformer, a first rectifier transformer and a second rectifier transformer; the voltage regulating transformer comprises: an on-load voltage regulating switch, and the on-load voltage regulating switch has a gear controller, and the gear controller is used to control the output voltage of the voltage regulating transformer; It also includes a control signal generator, the control signal generator is connected to a matrix switch, and the matrix switch is respectively connected to a plurality of gear controllers, a main and standby controllers, a remote controller, and a current feedback controller; The matrix switch is used to receive a control signal with a preset coding rule to control the corresponding switch to be turned on or off according to the control signal with the preset coding rule, wherein the control signal with the preset coding rule includes: a signal type field, a linkage field, and a control adjustment field, the signal type field represents a specific device connected to the switch matrix, the linkage field represents that after the current control device is completed, the next one or several control devices associated with the control device are automatically controlled, and the control adjustment field represents a specific control method.

2. The 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace according to claim 1, characterized in that: The input end of the transformer group is connected to the power supply, and the output end is respectively connected to the first rectifier cabinet and the second rectifier cabinet, the first output end of the first rectifier cabinet and the first output end of the second rectifier cabinet are connected to the first electrode, and the second output end of the first rectifier cabinet and the second output end of the second rectifier cabinet are connected to the second electrode, wherein the first electrode and the second electrode have opposite polarities.

3. The 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace according to claim 2, characterized in that: The input end of the voltage regulating transformer is connected to the power supply, the output end of the voltage regulating transformer is connected to the first rectifier transformer and the second rectifier transformer, the first rectifier transformer is connected to the first rectifier cabinet, and the second rectifier transformer is connected to the second rectifier cabinet.

4. The 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace according to claim 3, characterized in that: The first rectifier cabinet and the second rectifier cabinet both include a rectifier circuit, and the number of thyristors on each rectifier arm of the rectifier circuit is determined according to the rated DC current and DC voltage output by the transformer-rectifier device.

5. The 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace according to claim 4, characterized in that: The rectifier circuit is a double reverse star rectifier circuit, and the thyristors arranged on the same rectifier arm have a preset forward volt-ampere characteristic curve.

6. The 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace according to claim 1, characterized in that: At least a portion of the switch nodes of the matrix switch are further connected to a delay circuit, an output end of the at least a portion of the switch nodes is connected to a gear controller, and the control signal with a preset coding rule further includes a delay signal trigger field; The control signal generator is also used to set the signal type field to a field for controlling the gear controller and set the linkage field to a field for controlling the remote controller when it is determined that the thyristor control angle is less than a preset angle.

7. The 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace according to claim 6, characterized in that: The matrix switch is further used to control the corresponding delay circuit to be enabled when it is determined that the delay signal trigger field in the control signal of the preset coding rule is not empty.

8. The 36MVA manganese silicon alloy fully enclosed submerged arc DC ore furnace according to claim 1, characterized in that: A DC current sensor is provided at the output end of the transformer-rectifier device, and current transformers are provided at the input ends of the first rectifier transformer and the second rectifier transformer, and both the DC current sensor and the current transformer are connected to the control signal generator; The control signal generator is also used to set the signal type field to a field for controlling a current feedback controller and set the linkage field to a field for controlling a remote controller when it is determined that the feedback signal of the DC current sensor is lost or the feedback signal of the current transformer is lost.

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