CN203502497U - Measurement device of electrode impedance of three-electrode electric furnace - Google Patents
Measurement device of electrode impedance of three-electrode electric furnace Download PDFInfo
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- CN203502497U CN203502497U CN201320599634.4U CN201320599634U CN203502497U CN 203502497 U CN203502497 U CN 203502497U CN 201320599634 U CN201320599634 U CN 201320599634U CN 203502497 U CN203502497 U CN 203502497U
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Abstract
The utility model discloses a measurement device of electrode impedance of three-electrode electric furnace. The measurement device comprises a current measurement device, a voltage measurement device and a controller. The current measurement device comprises a first current transformer, a second current transformer and a third current transformer, the currents of three electrodes of the electric furnace are measured through the first current transformer, the second current transformer and the third current transformer respectively, and the first current transformer, the second current transformer and the third current transformer are connected in a triangular mode and arranged corresponding to the three electrodes respectively. The voltages of the three electrodes are measured through the voltage measurement device, and the voltage measurement device is respectively connected with the three electrodes. The controller is respectively connected with the current measurement device and the voltage measurement device, and the impedances of the three electrodes are respectively measured through the controller according to the currents and the corresponding voltages of the three electrodes. According to the measurement device, the accurate current values of the electrodes can be measured under the condition that loads are unbalanced, then the accurate impedance values of the electrodes are obtained, influences of short net tail end wiring are eliminated, and accurate judgment on and accurate control over the inserting depths of the electrodes and the power of the electric furnace are achieved.
Description
Technical field
The utility model relates to metallurgical technology field, particularly a kind of measurement mechanism of electrode impedance of three electrode electric furnaces.
Background technology
Electric furnace has a wide range of applications in smelting process, and wherein the Measurement accuracy of electrode impedance value has vital impact for judging electrode insertion depth and carrying out furnace power control.In the prior art, conventionally directly utilize the corresponding current transformer of each winding of furnace transformer to export to detect the electric current of counter electrode, thereby obtain electrode impedance value.
But, the shortcoming that prior art exists is, the leg-of-mutton connected mode of the general employing of electric furnace short net end, only in the situation that the balancing the load of three electrodes, the electrode impedance value measuring is only accurately, in other cases, all can there is deviation in the electrode impedance value measuring, thereby cannot obtain electrode impedance value accurately.
Utility model content
The purpose of this utility model is intended to solve at least to a certain extent above-mentioned technological deficiency.
For this reason, the purpose of this utility model is to propose a kind of measurement mechanism of electrode impedance of three electrode electric furnaces, this measurement mechanism connects three current transformers in leg-of-mutton mode, thereby load unbalanced in the situation that, also can measure electrode impedance value accurately, eliminate the impact of short net end wiring.
For achieving the above object, the measurement mechanism of the electrode impedance of a kind of three electrode electric furnaces that the utility model proposes, comprise: current measurer, described current measurer comprises the first current transformer, the second current transformer and the 3rd current transformer of respectively electric current of three of electric furnace electrodes being measured, described the first current transformer, the second current transformer and the 3rd current transformer are connected in leg-of-mutton mode, and described the first current transformer, the second current transformer and the 3rd current transformer should arrange with described three electrode pairs respectively; The voltage measurement device that the voltage of described three electrodes is measured, described voltage measurement device is connected respectively with described three electrodes; Controller, described controller is connected respectively with voltage measurement device with described current measurer, the impedance that the voltage that described controller is answered according to the electric current of described three electrodes and three electrode pairs calculates respectively described three electrodes.
According to the measurement mechanism of the electrode impedance of the three electrode electric furnaces that the utility model proposes, the first current transformer, the second current transformer is connected in leg-of-mutton mode with the 3rd current transformer, and the electric current of three of electric furnace electrodes is measured, and voltage measurement device is connected respectively with three electrodes, and the voltage of three electrodes is measured, the impedance that the voltage that controller is answered according to the electric current of three electrodes and three electrode pairs calculates respectively three electrodes, thereby measurement mechanism of the present utility model can measure electrode current value accurately in the situation that three electrodes are load unbalanced, and then obtain electrode impedance value accurately, improve measuring accuracy, eliminate the impact of short net end wiring, realize accurate judgement and the control of electrode insertion depth and furnace power.
Further, described voltage measurement device is threephase potential transformer, and the armature winding of described threephase potential transformer is all connected in the mode of star with secondary winding.
Particularly, described the first current transformer, the second current transformer and the 3rd current transformer be corresponding being arranged on secondary three phase windings of furnace transformer respectively, or correspondence is arranged on be connected with secondary three phase windings of described furnace transformer short online respectively.
Preferably, the measurement mechanism of the electrode impedance of three above-mentioned electrode electric furnaces, also comprise: multifunction instrument, described multifunction instrument is connected between described controller and described current measurer, and be connected between described controller and described voltage measurement device, electric current and the voltage of described three electrodes of described multifunction instrument display measurement, and the electric current of described three electrodes and voltage are sent to described controller.Wherein, described controller can be PLC controller.
The aspect that the utility model is additional and advantage in the following description part provide, and part will become obviously from the following description, or recognize by practice of the present utility model.
Accompanying drawing explanation
Above-mentioned and/or the additional aspect of the utility model and advantage will become from the following description of the accompanying drawings of embodiments and obviously and easily understand, wherein:
Fig. 1 is according to the block diagram of the measurement mechanism of the electrode impedance of the three electrode electric furnaces of the utility model embodiment;
Fig. 2 is according to the block diagram of the measurement mechanism of the electrode impedance of three electrode electric furnaces of a specific embodiment of the utility model;
Fig. 3 is according to the block diagram of the measurement mechanism of the electrode impedance of three electrode electric furnaces of a preferred embodiment of the utility model; And
Fig. 4 is according to the process flow diagram of the measuring method of the electrode impedance of the three electrode electric furnaces of the utility model embodiment.
Embodiment
Describe embodiment of the present utility model below in detail, the example of described embodiment is shown in the drawings, and wherein same or similar label represents same or similar element or has the element of identical or similar functions from start to finish.Below by the embodiment being described with reference to the drawings, be exemplary, only for explaining the utility model, and can not be interpreted as restriction of the present utility model.
Disclosing below provides many different embodiment or example to be used for realizing different structure of the present utility model.Of the present utility model open in order to simplify, hereinafter the parts of specific examples and setting are described.Certainly, they are only example, and object does not lie in restriction the utility model.In addition, the utility model can be in different examples repeat reference numerals and/or letter.This repetition is in order to simplify and object clearly, itself do not indicate the relation between discussed various embodiment and/or setting.In addition, the various specific technique that the utility model provides and the example of material, but those of ordinary skills can recognize the property of can be applicable to of other techniques and/or the use of other materials.In addition, First Characteristic described below Second Characteristic it " on " structure can comprise that the first and second Characteristics creations are for the direct embodiment of contact, also can comprise the embodiment of other Characteristics creation between the first and second features, such the first and second features may not be direct contacts.
In description of the present utility model, it should be noted that, unless otherwise prescribed and limit, term " installation ", " being connected ", " connection " should be interpreted broadly, for example, can be mechanical connection or electrical connection, also can be the connection of two element internals, can be to be directly connected, and also can indirectly be connected by intermediary, for the ordinary skill in the art, can understand as the case may be the concrete meaning of above-mentioned term.
With reference to description and accompanying drawing below, by these and other aspects of clear embodiment of the present utility model.In these descriptions and accompanying drawing, specifically disclose some specific implementations in embodiment of the present utility model, represent to implement some modes of the principle of embodiment of the present utility model, but should be appreciated that the scope of embodiment of the present utility model is not limited.On the contrary, embodiment of the present utility model comprises spirit and all changes within the scope of intension, modification and the equivalent that falls into additional claims.
Measurement mechanism and the measuring method thereof of the electrode impedance of the three electrode electric furnaces that propose according to the utility model embodiment are described with reference to the accompanying drawings.
Fig. 1 is according to the block diagram of the measurement mechanism of the electrode impedance of the three electrode electric furnaces of the utility model embodiment.As shown in Figure 1, the measurement mechanism of the electrode impedance of this three electrodes electric furnace comprises: current measurer 10, voltage measurement device 20, controller 30.
Wherein, current measurer 10 comprises the first current transformer the Ta respectively electric current of three of electric furnace electrodes being measured, the second current transformer Tb and the 3rd current transformer Tc, wherein, the first current transformer Ta, the second current transformer Tb is connected in leg-of-mutton mode with the 3rd current transformer Tc, say, 1 end of the first current transformer Ta is connected with 2 ends of the 3rd current transformer Tc, 2 ends of the first current transformer Ta are connected with 1 end of the second current transformer Tb, 2 ends of the second current transformer Tb are connected with 1 end of the 3rd current transformer Tc.And, the first current transformer Ta, the second current transformer Tb and the 3rd current transformer Tc should arrange with three electrode pairs respectively, that is to say, the installation site of the first current transformer Ta, the second current transformer Tb and the 3rd current transformer Tc respectively should with three electrode pairs, for example, 2 ends of the first current transformer Ta are connected with electrode 2, and 2 ends of the second current transformer Tb are connected with electrode 3, and 2 ends of the 3rd current transformer Tc are connected with electrode 1.Particularly, the first current transformer Ta, the second current transformer Tb and the 3rd current transformer Tc can be all single-phase current transformer.
As shown in Figure 1, the voltage of 20 pairs of three electrodes of voltage measurement device is measured, and voltage measurement device 20 is connected respectively with three electrodes.Controller 30 is connected respectively with voltage measurement device 20 with current measurer 10, the impedance that the voltage that controller 30 is answered according to the electric current of three electrodes that measure and three electrode pairs calculates respectively three electrodes.
Particularly, controller 30 calculates respectively the impedance of three electrodes according to Ohm law, the impedance of calculating respectively three electrodes according to following formula:
Wherein, I is the electric current of three electrodes, and U is the corresponding voltage of three electrodes, and R is the corresponding impedance of three electrodes.
In specific embodiment of the utility model, as shown in Figure 2, voltage measurement device 20 can be threephase potential transformer, and the armature winding of threephase potential transformer is all connected in the mode of star with secondary winding.
As shown in Figure 1 or 2, the first current transformer Ta, the second current transformer Tb and the 3rd current transformer Tc can be respectively corresponding be arranged on be connected with secondary three phase windings of furnace transformer 40 short on the net.It should be noted that, short net also claims heavy current circuit, refers to the general name of the carrying object that (comprises electrode) from transformer secondary leading-out terminal to electrode.I.e. speech, 1 end of 1 end of the first current transformer Ta, the second current transformer Tb and 1 end of the 3rd current transformer Tc are connected with the leading-out terminal of secondary three phase windings of furnace transformer 40 respectively.
In addition, the first current transformer Ta, the second current transformer Tb and the 3rd current transformer Tc are can also be respectively corresponding is arranged on secondary three phase windings of furnace transformer 40.
At the utility model, be in an example, as shown in Figure 1 or 2, secondary three phase windings of furnace transformer 40 can connect in leg-of-mutton mode, and elementary three phase windings of furnace transformer 40 can connect in the mode of star.
In preferred embodiment of the utility model, as shown in Figure 3, the measurement mechanism of the electrode impedance of three above-mentioned electrode electric furnaces also comprises: multifunction instrument 50.Wherein, multifunction instrument 50 is connected between controller 30 and current measurer 10, and be connected between controller 30 and voltage measurement device 20, electric current and the voltage of three electrodes of multifunction instrument 50 display measurements, and the electric current of three electrodes and voltage are sent to controller 30.
Wherein, controller 30 can be PLC controller, multifunction instrument 50 has communication interface, for example communication interface can adopt Profibus communications protocol, and by the communication interface of multifunction instrument 50, realize the electric current of three electrodes measuring with transmission current measuring appliance 10 with the communication of controller 30 and three voltages that electrode pair is answered that voltage measurement device 20 is measured.
In embodiment of the present utility model, utilize a multifunction instrument 50, three single-phase current transformers, a threephase potential transformer, by three current transformers are connected in leg-of-mutton mode, the measurement of realization to the electric current of three electrodes, and the armature winding by a threephase potential transformer is all connected in the mode of star with secondary winding, the measurement of realization to the corresponding voltage of three electrodes, the electric current of three above-mentioned electrodes and corresponding voltage transfer to PLC controller by the communication interface of multifunction instrument, PLC controller is according to Ohm law, calculate the corresponding impedance of three electrodes.
The measurement mechanism of the electrode impedance of the three electrode electric furnaces that propose according to the utility model embodiment, the first current transformer, the second current transformer is connected in leg-of-mutton mode with the 3rd current transformer, and the electric current of three of electric furnace electrodes is measured, and voltage measurement device is connected respectively with three electrodes, and the voltage of three electrodes is measured, the impedance that the voltage that controller is answered according to the electric current of three electrodes and three electrode pairs calculates respectively three electrodes, thereby measurement mechanism of the present utility model can measure electrode current value accurately in the situation that three electrodes are load unbalanced, and then obtain electrode impedance value accurately, improve measuring accuracy, eliminate the impact of short net end wiring, realize accurate judgement and the control of electrode insertion depth and furnace power.
Fig. 4 is according to the process flow diagram of the measuring method of the electrode impedance of the three electrode electric furnaces of the utility model embodiment.As shown in Figure 4, the measuring method of the electrode impedance of this three electrodes electric furnace comprises the following steps:
S1, measures the electric current of three of electric furnace electrodes respectively by the first current transformer, the second current transformer and the 3rd current transformer.Wherein, the first current transformer, the second current transformer and the 3rd current transformer are connected in leg-of-mutton mode.
Wherein, the first current transformer, the second current transformer and the 3rd current transformer be corresponding being arranged on secondary three phase windings of furnace transformer respectively, or correspondence is arranged on be connected with secondary three phase windings of furnace transformer short online respectively.It should be noted that, short net also claims heavy current circuit, refers to the general name of the carrying object that (comprises electrode) from transformer secondary leading-out terminal to electrode.
S2, measures the voltage of three electrodes by threephase potential transformer.Wherein, the armature winding of threephase potential transformer is all connected in the mode of star with secondary winding.
In an embodiment of the present utility model, can also pass through electric current and the voltage of three electrodes of multifunction instrument display measurement, and electric current and the voltage of three electrodes measuring are sent to controller.
S3, the impedance that the voltage of answering according to the electric current of three electrodes and three electrode pairs calculates respectively three electrodes.
Controller is according to the electric current of three electrodes and three voltages that electrode pair is answered, and the impedance of calculating respectively three electrodes according to Ohm law, the impedance of calculating respectively three electrodes according to following formula:
Wherein, I is the electric current of three electrodes, and U is the corresponding voltage of three electrodes, and R is the corresponding impedance of three electrodes.
The measuring method of the electrode impedance of the three electrode electric furnaces that propose according to the utility model embodiment, by the first current transformer connecting in leg-of-mutton mode, the second current transformer and the 3rd current transformer are measured the electric current of three of electric furnace electrodes respectively, and by threephase potential transformer, the voltage of three electrodes is measured, and the impedance of calculating respectively three electrodes according to the voltage that the electric current of three electrodes and three electrode pairs are answered, thereby measuring method of the present utility model can measure electrode current value accurately in the situation that three electrodes are load unbalanced, and then obtain electrode impedance value accurately, improve measuring accuracy, eliminate the impact of short net end wiring, realize accurate judgement and the control of electrode insertion depth and furnace power.
In process flow diagram or any process of otherwise describing at this or method describe and can be understood to, represent to comprise that one or more is for realizing the module of code of executable instruction of the step of specific logical function or process, fragment or part, and the scope of preferred implementation of the present utility model comprises other realization, wherein can be not according to order shown or that discuss, comprise according to related function by the mode of basic while or by contrary order, carry out function, this should be understood by embodiment person of ordinary skill in the field of the present utility model.
The logic and/or the step that in process flow diagram, represent or otherwise describe at this, for example, can be considered to for realizing the sequencing list of the executable instruction of logic function, may be embodied in any computer-readable medium, for instruction execution system, device or equipment (as computer based system, comprise that the system of processor or other can and carry out the system of instruction from instruction execution system, device or equipment instruction fetch), use, or use in conjunction with these instruction execution systems, device or equipment.With regard to this instructions, " computer-readable medium " can be anyly can comprise, storage, communication, propagation or transmission procedure be for instruction execution system, device or equipment or the device that uses in conjunction with these instruction execution systems, device or equipment.The example more specifically of computer-readable medium (non-exhaustive list) comprises following: the electrical connection section (electronic installation) with one or more wirings, portable computer diskette box (magnetic device), random-access memory (ram), ROM (read-only memory) (ROM), the erasable ROM (read-only memory) (EPROM or flash memory) of editing, fiber device, and portable optic disk ROM (read-only memory) (CDROM).In addition, computer-readable medium can be even paper or other the suitable medium that can print described program thereon, because can be for example by paper or other media be carried out to optical scanning, then edit, decipher or process in electronics mode and obtain described program with other suitable methods if desired, be then stored in computer memory.
Should be appreciated that each several part of the present utility model can realize with hardware, software, firmware or their combination.In the above-described embodiment, a plurality of steps or method can realize with being stored in storer and by software or the firmware of suitable instruction execution system execution.For example, if realized with hardware, the same in another embodiment, can realize by any one in following technology well known in the art or their combination: have for data-signal being realized to the discrete logic of the logic gates of logic function, the special IC with suitable combinational logic gate circuit, programmable gate array (PGA), field programmable gate array (FPGA) etc.
Those skilled in the art are appreciated that realizing all or part of step that above-described embodiment method carries is to come the hardware that instruction is relevant to complete by program, described program can be stored in a kind of computer-readable recording medium, this program, when carrying out, comprises step of embodiment of the method one or a combination set of.
In addition, each functional unit in each embodiment of the utility model can be integrated in a processing module, can be also that the independent physics of unit exists, and also can be integrated in a module two or more unit.Above-mentioned integrated module both can adopt the form of hardware to realize, and also can adopt the form of software function module to realize.If described integrated module usings that the form of software function module realizes and during as production marketing independently or use, also can be stored in a computer read/write memory medium.
The above-mentioned storage medium of mentioning can be ROM (read-only memory), disk or CD etc.
In the description of this instructions, the description of reference term " embodiment ", " some embodiment ", " example ", " concrete example " or " some examples " etc. means to be contained at least one embodiment of the present utility model or example in conjunction with specific features, structure, material or the feature of this embodiment or example description.In this manual, the schematic statement of above-mentioned term is not necessarily referred to identical embodiment or example.And the specific features of description, structure, material or feature can be with suitable mode combinations in any one or more embodiment or example.
Although illustrated and described embodiment of the present utility model, for the ordinary skill in the art, be appreciated that in the situation that not departing from principle of the present utility model and spirit and can carry out multiple variation, modification, replacement and modification to these embodiment, scope of the present utility model is by claims and be equal to and limit.
Claims (5)
1. a measurement mechanism for the electrode impedance of three electrode electric furnaces, is characterized in that, comprising:
Current measurer, described current measurer comprises the first current transformer, the second current transformer and the 3rd current transformer of respectively electric current of three of electric furnace electrodes being measured, described the first current transformer, the second current transformer and the 3rd current transformer are connected in leg-of-mutton mode, and described the first current transformer, the second current transformer and the 3rd current transformer should arrange with described three electrode pairs respectively;
The voltage measurement device that the voltage of described three electrodes is measured, described voltage measurement device is connected respectively with described three electrodes; And
Controller, described controller is connected respectively with voltage measurement device with described current measurer, the impedance that the voltage that described controller is answered according to the electric current of described three electrodes and three electrode pairs calculates respectively described three electrodes.
2. the measurement mechanism of the electrode impedance of three electrode electric furnaces as claimed in claim 1, is characterized in that, described voltage measurement device is threephase potential transformer, and the armature winding of described threephase potential transformer is all connected in the mode of star with secondary winding.
3. the measurement mechanism of the electrode impedance of three electrode electric furnaces as claimed in claim 1, it is characterized in that, described the first current transformer, the second current transformer and the 3rd current transformer be corresponding being arranged on secondary three phase windings of furnace transformer respectively, or correspondence is arranged on be connected with secondary three phase windings of described furnace transformer short online respectively.
4. the measurement mechanism of the electrode impedance of three electrode electric furnaces as described in any one in claim 1-3, is characterized in that, also comprises:
Multifunction instrument, described multifunction instrument is connected between described controller and described current measurer, and be connected between described controller and described voltage measurement device, electric current and the voltage of described three electrodes of described multifunction instrument display measurement, and the electric current of described three electrodes and voltage are sent to described controller.
5. the measurement mechanism of the electrode impedance of three electrode electric furnaces as claimed in claim 1, is characterized in that, described controller is PLC controller.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320599634.4U CN203502497U (en) | 2013-09-26 | 2013-09-26 | Measurement device of electrode impedance of three-electrode electric furnace |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201320599634.4U CN203502497U (en) | 2013-09-26 | 2013-09-26 | Measurement device of electrode impedance of three-electrode electric furnace |
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| CN203502497U true CN203502497U (en) | 2014-03-26 |
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| CN201320599634.4U Withdrawn - After Issue CN203502497U (en) | 2013-09-26 | 2013-09-26 | Measurement device of electrode impedance of three-electrode electric furnace |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103472305A (en) * | 2013-09-26 | 2013-12-25 | 中国恩菲工程技术有限公司 | Measurement device and measurement method of electrode impedance of three-electrode electric furnace |
| CN105529965A (en) * | 2016-01-19 | 2016-04-27 | 奇瑞汽车股份有限公司 | Brushless direct current motor position detection circuit |
| CN107643477A (en) * | 2017-10-20 | 2018-01-30 | 中国恩菲工程技术有限公司 | Open arc electric furnace arc length detection means |
-
2013
- 2013-09-26 CN CN201320599634.4U patent/CN203502497U/en not_active Withdrawn - After Issue
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103472305A (en) * | 2013-09-26 | 2013-12-25 | 中国恩菲工程技术有限公司 | Measurement device and measurement method of electrode impedance of three-electrode electric furnace |
| CN103472305B (en) * | 2013-09-26 | 2016-03-30 | 中国恩菲工程技术有限公司 | The measurement mechanism of the electrode impedance of three electrode electric furnaces and measuring method thereof |
| CN105529965A (en) * | 2016-01-19 | 2016-04-27 | 奇瑞汽车股份有限公司 | Brushless direct current motor position detection circuit |
| CN105529965B (en) * | 2016-01-19 | 2018-07-06 | 奇瑞汽车股份有限公司 | A kind of position detecting circuit for brushless direct current dynamo |
| CN107643477A (en) * | 2017-10-20 | 2018-01-30 | 中国恩菲工程技术有限公司 | Open arc electric furnace arc length detection means |
| CN107643477B (en) * | 2017-10-20 | 2023-09-05 | 中国恩菲工程技术有限公司 | Arc length detector for arc-starting electric furnace |
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