The digitlization of electric welder

Time:2023-06-28 13:54:49
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source:GEOFF CNC Machining

Normal > summary: The article combines digital signal to handle technical characteristic, integration analysis the advantage that digitlizes welder. The development general situation that two parts introduced the main circuit that electric welder is aimed at on the foundation here and control circuit to digitlize and implementation method. Finally, the article introduced Beijing industry university to study the work in the part that digitlizes welder respect. Keyword: Solder processing of signal of introductive number of control of power source, digitlization, DSP is opposite at imitate signal processing has very big advantage, expression is in precision tall, flexibility big, dependability is good and easily the respect such as large scale integration. It is with recording system exemple, the letter a confusion of voices of imitate recording system is compared control in 60 decibel commonly, and the letter a confusion of voices of a 16 digital recording system is compared can achieve 96 decibel, recording system of tower above imitate 60 multiple [1] . Technology of digital signal processing is in accordingly processing of communication, speech, graph / wide application received inside a lot of domain such as electron of electron of appearance of image processing, automata, instrument, medicine, military affairs and sophisticated science and technology, computer and workstation, consumption. Handle the product of technology and union of arc solder craft as digital signal, the occurrence that digitlizes welder caused the wide attention of the personage inside course of study. The focus of attention, it is the concept that digitlization solders and its characteristic above all, it is the implementation means that digitlizes welder next, finally is to digitlize welder to receive those who manufacture technology to urge action to whole solder. Because 1 digitlization welder and its characteristic compare evening to digitlize what welder appears, for example Fronius is the production that just began to undertake digitlizing welder 1998, what had not formed digitlization welder so far accordingly is unified, get the definition of each respect self-identity. We understand, alleged digitlization welder ought to be to point to such a few welder, their main control circuit is replaced by digital technology place directly by traditional imitate technique, the digital signal that the control signal in dominating circuit also transfers to code to 0/1 by imitate signal subsequently. The experience in the development that controls a technology in computation crosses two crucial level, initiate period and period of direct figure control namely. In initiate period, speed of all of computer science department slow, price is high, fluky also, because the computational control of this phase is main,undertake with two kinds of means, a kind of means is the computer prints an instruction to give handlers, another kind of means is the set value of adjuster of computer modification simulation. After entering direct figure to dominate period, the set that confine dictates at be being sent to handlers and revises imitate regulator no longer is worth the task of the computer, the function that superseded imitate adjuster directly however [2] . Ought to point out, there are two as similar as this levels likewise in the development that digitlizes welder. With 8098 or what 80C196 is a delegate is odd power source of control arc solder basically belongs to a machine the product that digitlizes welder to initiate period. Its are main the feature is odd the management that the main effect in welder is the welder that finish mixes a machine solder of parameter give, solder control of the constant voltage in craft, constant current passes simulative PI controller to finish. Of course this is not absolutely, not all sheet piece machine pilot arc solder power source is to use sheet merely piece machine finished solder of parameter give. In certain sheet piece in welder of machine pilot silicon controlled rectifier, from parameter set, solder control of parameter feedback sampling, PI, spark to silicon controlled rectifier all the time the happening of pulse is by sheet piece machine finish. What this kind of circumstance falls is odd arc solder power source ought to belong to a machine pilot the product of period of direct figure control. In some sense, in digitlization only welder entered direct digitlization phase to just realize digitlization truly, a variety of dominant positions that just filled fission to reveal digitlization to control place to bring. Tell on the whole, control of imitate of digitlization control be superior to basically behaves good in flexibility, stability precision of strong, control compatibility of tall, interface is good wait for a few respects. Self-evident, digitlization control has very good system flexibility. To imitate system, systematic configuration and gain hold the decision of hardware parameter place such as the network by block, once decide very difficult change. And to digital system, all these is change software merely just. To digitlization welder, flexibility is meant same cover hardware circuit to be able to come true to solder differently technology control, solder to differring technique and material of different welding wire, diameter can choose parameter of different control strategy, control, make welder is coming true thereby muti_function compositive while, avery kind of solders the craft effect of technique also will get substantially rise. Solder with CO2 the undee control that short circuit transfers is exemple, the voltaic weaveform when short circuit decided its solder the stand or fall that splattering size and welding line shape, and be mixed to different welding wire diameter solder craft interval, weaveform of first-rate electric current can be distinguished somewhat. When using imitate to control, we often are according to give attention to two or morethings the principle of whole craft interval chooses voltaic weaveform, what cause the craft effect of partial interval necessarily so is not ideal. Those who digitlize pilot flexibility to also reflect the control software in digitlization welder at the same time is online on the function that upgrade. At present the more advanced digitlization welder on the technology is on the choice of memory from E2PROM excessive arrived Flash, also increased function of on-line Flash process designing on circuit design. Accordingly, the control program that digitlizes welder to this kind upgrades or online debug revise, need E2PROM no longer insert unplug, cleared, process designing writes ultraviolet ray, undertake through interface of general RS232 serial communication Flash process designing will finish simply however. The 2nd advantage that digitlizes welder is it has stronger stability. In imitate system, the processing of signal undertakes through active or sth resembling a net of passive electrified wire netting, the set that handles parameter passes the choice of parameter of resistor, capacitance to finish. The tolerance that allows parameter in the block in imitate system so, drift causes the change of controller parameter necessarily, on one hand stability of imitate pilot temperature is poorer, the product consistency when on the other hand imitate is controlled assures hard. And in digitlizing control, the processing of signal or control are carried out algorithmicly is those who pass software add / decrease, by / will finish except operation, its stability is accordingly good, the consistency of the product also got very good assurance. Digitlization welder has taller control precision. The amplifier of operation of sum of errors that imitate pilot precision joins numerical value to cause by component commonly is not ideal and characteristic parameter (wait like Ad, ACM, UOS, IOS, noise) the error place decision that cause. The opposite error that causes enlarge multiple with network of retrorse amplifier resistor is exemple, enlarge multiple, its are opposite error, the opposite error that resistor R1 and R2 are here [3] . If R1 is mixed,the opposite error of R2 is ± together 5% , magnify diploid opposite error is ± 10% . The error of actual imitate enlarge circuit wants far under this numerical value, want to make sure R1 and R2 have identical opposite error only, what assure R2 and R1 ratio namely is accurate, can obtain accurate enlarge multiple. Although R1 and R2 are unequal, all slant when the error or slant negative also can compensate one part error. But the error that because multistage is handled,imitate controls accumulates the enlarge pursueing course with noise, its overall error is accordingly taller. And digitlization pilot precision is mere with the model - number changes quantify error and system finite word is long about, if be opposite,the signal that a 0~10V changes has 10 models - if number is changed, model - number is changed quantify an error mediumly to be, because this is digitlized,control often can obtain very tall precision. The interface compatibility that digitlizes welder is good. Because digitlized welder to use sheet in great quantities piece the digital chip such as machine, DSP, the communication interface between the power source with PC and digitlization welder, digitlization welder and robot and digitlization accordingly inner welder and device of machine sending silk, power source and water-cooling, power source and welding torch is very OK come true conveniently. The development that believes to produce network management as contemporary solder deliver a child and gain ground, digitlization welder can produce mainer and mainer effect necessarily with its good interface compatibility. Digitlization welder is had control the dominant position with welder more unquestionable than having photograph with traditional imitate. But, handling speed to be differred slow with interference rejection ability is digital pilot main drawback, because this is in the implementation that digitlizes welder,must pass logical control chip choice and integral design satisfy arc solder craft to ask to handling the lowest of speed, and should take significant interference rejection step, the arc solder craft that makes the number controls circuit to get used to tall radiate, strong electromagnetism to disturb environment. The implementation welder of 2 digitlization welder develops to digitlization direction, contain the content of two respects. One is the digitlization of main circuit, another is the digitlization that dominates circuit. 2.

The digitlization of 1 main circuit pursues block diagram of main circuit of 1 imitate welder solders the characteristic that power source has low voltage, big electricity, solder to satisfy power source this characteristic requirement, can come true through a variety of design means. Soldering in the design of power source, the design of transformer is crucial. Soldering in power source, transformer satisfies electric current, voltage on one hand match a requirement, mix to power transmission loop on the other hand solder loop undertakes electric segregation. More important is transformer transmitted the position in loop to decide to solder in energy the bulk of power source and quality. Graph weaveform of electric current of output of 2 imitate welder pursues the 2 main circuit block diagram that are imitate type welder. This kind of power source is mixed by bridge of commutate of transformer of frequency of a labour, three-phase composition of a transistor group, transistor group is equivalent to laden series connection resistor in the action in loop. Transistor group work is magnifying area, the voltage that in soldering, does not need uses up the C in transistor group, E pole between, power comsumption is accordingly great, transistor group needs water-cooling. The advantage of this kind of welder is to answer speed fast, the specific power consumption that defect is transistor group is big, because this basically has been replaced by the power source place of other type. Differ with imitate type welder, in switch power source transistor group work is in switch condition, main circuit is shown 3 times like the graph. Switch power source basically is mixed by bridge of labour frequency transformer, commutate semiconductor switch composition. Semiconductor switch secures frequency to debut periodicly according to some / close (if every second is enlightened / close, corresponding frequency 20KHz) , if will analyse the circuit that the graph shows 3 times with ideal switch, no matter be,still close position in liberal position, the loss of switch is 0. Graph the main circuit block diagram of 3 switch power source is in real work, because use IGBT, MOSFET or bipolar transistor regard switch as parts of an apparatus, total meeting is put in certain power loss, but compare with the loss photograph of imitate welder, this loss is negligible not plan. It is with power source of switch of a 20KW exemple, it is voltage drive more as a result of switch of electron of contemporary electric power model, needs electricity is dinky, the power that controls circuit to need a few tile only can satisfy a requirement. Besides efficiency tall and outside, switch power source the working frequency that another advantage is it is tall. The working frequency of switch power source is taller, criterion the ripple of loop output electric current is smaller, answer speed faster, because this welder obtained better trends,answer character. Watch 1 listed the different switch parts of an apparatus that uses in switch welder and the typical switch frequency that answer relatively to it. The switch parts of an apparatus that in expressing 1 switch power source, uses - switch frequency adjusts to be inside a wider range in switch power source power output, spark of pulse guide a time and the rate that pass time (or occupy sky comparing) must adjustable. If the graph is shown 4 times, occupy sky comparing tall the cost of average electric current with a higher output, occupy sky comparing low the value of average electric current with an inferior output. This kind adjusts means calls pulse width adjustment (PWM) . The control circuit of PWM form is used in power source of all inversion of switch of fully control power and switch power source almost at present. Graph the output electric current of 4 switch power source solders power source develops switch type welder from imitate type welder, was to finish actually solder power source arrives from imitate of digitlization span. Solder the digitlization of power source main circuit makes solder power source obtained on the function of two respects rise: 1.

Solder the power loss of power source decreases greatly, make solder the efficiency of power source achieves 90% above. 2.

As working frequency rise, the ripple of loop output electric current is smaller, answer speed faster, because this welder obtained better trends,answer character. In the design of transformer, we often use formula 1, (formulary 1) in type: The inductive electromotive force that V1 is transformer, the unit is V; Bm is the maximum of the magnetic flux density of transformer core material, unit T; N1 is the v/LIT all over the ground number of winding of transformer former edge; S is core cut area, unit Cm2; F is the working frequency of transformer, unit Hz; Graph 5 transformer bulk - curve of working frequency relation accordingly, the quality of transformer, bulk and frequency become inverse ratio. The working frequency of transformer is taller, namely F is bigger, criterion the cut area S that the N1 of v/LIT all over the ground number of transformer winding reachs core lesser is smaller, because its quality exceeds small, volume,jump over small. Graph 5 for transformer bulk - frequency curve. If put transformer at the back of of switch parts of an apparatus, if the graph is shown 6 times, we got the main circuit structure of power source of arc solder inversion. At this moment, the working frequency of transformer increases the inversion frequency of the 20KHz that often mentions to us by 50Hz, some designs can achieve 100KHz even. Because power source of inversion of this arc solder and photograph of switch power source are compared, had volume again the advantage with small, light quality. Graph brilliant brake is in charge of traceable of power source of inversion of solder of arc of block diagram of main circuit of power source of 6 inversion type power source of inversion arc solder, although the voltage of brilliant brake canal reachs voltaic capacity to be able to be made taller, pilot power is great, but because it is parts of an apparatus of a kind of half control switch, once spark hind cannot close by oneself, because this needs to close compulsively, cause circuit complex. The switch rate that at the same time brilliant brake provides is slow, working frequency is low, can work only inside the limits under 5KHz. Begin from 80 time, no matter power switch parts of an apparatus is in on sort, still be in capacity (grade of electric current, voltage) went up to have very great progress. From the point of current application, using MOSFET, IGBT to regard power as switch is the mainstream of power source of arc solder inversion, have to intelligent power module (SPIC) the tendency that way develops. 2.

The filter wave that the digitlization number signal of 2 control circuit is in reason imitate signal, model / number is changed, digitlization processing, number / the model is changed, the link composition such as flowing filter wave, control of final output imitate measures the digitlization that finishs pair of imitate signal thereby to handle. Handle link to digitlization, on current state of technology, we can choose digital signal processor roughly (DSP) , general microprocessor (MPU) , small controller (MCU) regard processing as 3 kinds chip. General microprocessor (MPU) apply at the computer in great quantities (PC) , as a result of its bulk taller, price compares big, power comsumption tall, although have very loud number signal to handle ability, but use in industrial control rarely, especially embedded systematic application. Application is more general is small controller and digital signal processor. Small controller is the sheet that domestic place says piece machine, have stronger incident to handle ability, interrupt, I/O is resourceful, home passes ten years, development of nearly 20 years applies, chinese material is more, the condition of soft, hardware of development is better. But the data processing ability of small controller lags behind at data signal processor far, often be in system of generous of real time sex, data processing insufficient. The English definition of digital signal processor if: In Brief, DSPs Are Processors Or Microcomputers Whose Hardware, software, and Instruction Sets Are Optimized For High-speed Numeric Processing Applications, An Essential For Processing Digital Data Representing Analog Signals In Real Time.

[Because digital signal handled appliance to have,4] is stronger data processing ability, it is in embedded extremely wide application received in the system, if card of mobile phone, sound, image collects card, motor control,wait a moment. To rise additionally general microprocessor is mixed the data processing ability of small controller, DSP has as shirt-sleeve as both tendency. The function that blended in DSP like the general microprocessor after Pentium MMX in order to improve network function, and 32 TriCore set of Xi Menzi is single a machine RISC (MPU) , the function of MCU and DSP is compositive in the kernel in a chip [5] . Normal Align=center> graph of the power source of arc solder inversion with the control system common block diagram of power source of inversion of solder of arc of 7 imitate control show 7 times like the graph, dominating return circuit is the imitate system that forms by passive or active parts of an apparatus. Solder the parameter such as electric current, voltage carries sensor LEM piece sampling, negative feedback arrives control loop. Feedback quantity and give signal to compare, dominate chip to PWM through PI controller output, PWM signal sparks through power enlarge, segregation of power switch component guide / close, the closed-loop control of the system that finish. The weakness with imitate control the oldest system is the capacity that has complex processing finite, yuan amount of parts of an apparatus is much, and the parameter of controller establishs the parameter decision of component by divide into equal parts of resistor, capacitance, of controller debug complex, flexibility difference. At the same time the parameter of resistor, capacitance distributings the consistency that affects controller, if temperature drift affects the stability of controller,the stability of parameter is differred. Because this is necessary,have the research of the digitlization of power source of arc solder inversion. Odd a machine pilot power source of arc solder inversion is power source of arc solder inversion a very important level in digitlizing control. Normal Align=center> pursues 8 sheet piece the control system block diagram of power source of inversion of solder of engine control arc is odd the principle block diagram of power source of arc solder inversion is like a machine pilot the graph is shown 8 times. Odd in this kind of system an engine is main the gives function and welder overall government that finished control signal. Odd although a machine is given in what signal finished merely in controlling a system, but this has made power source of arc solder inversion solders in implementation when craft is controlled, wait like CO2 weaveform control, obtain huge flexibility. Can carry sheet for example piece machine give out the CO2 short-circuit current of a variety of slope, different amplitude is undee, make the craft effect that CO2 solders can is close to inside distinct voltaic range at optimal. In the meantime, in sheet piece we notice machine pilot in power source of arc solder inversion its control core, PI controller and PWM control circuit are made by imitate component, PI controller is core with operation amplifier, PWM controls circuit to use SG3525 or SG3526 more. Use sheet piece machine although the control that has power supply of arc solder inversion is in of signal gave a part to realize digitlization, but get odd the limitation of a capability of machine oneself processing, the PI controller of power source and PWM still used imitate circuit. Accordingly, the characteristic of digitlization is in odd piece machine pilot solders did not get be reflectinged adequately in inversion power source. Normal Align=center>normal Align=center> pursues the electricity that the control cycle with 9 different choices gets answers a curve the Matlab that we carry power supply of pair of arc solder inversion emulates research to make clear, it is to the job below 20KHz inversion frequency, output inductance is the power source of arc solder inversion of 80uH, cycle of its the longest control is 100us. Graph the 9 control cycle that differ to use undertake Matlab of pilot of constant current of power source of arc solder inversion emulates place to reach electric current answers a curve. Emulate in the begining voltaic set-point is 100A, emulate 0.

The electric current when 01 seconds is given jump by 100A change 150A. By the graph 9 visible, if control cycle to be more than 100us, the extension that controls cycle will make the constant current of power source or effect of constant voltage control worsen quickly. And to general sheet piece for machine, the model is finished inside 100us - number is changed, PI operation, show, the processing such as PWM output is impossible. Accordingly, the for implementation PI controller and PWM digitlization in the design of digital control circuit in power source of arc solder inversion must choose to dominate chip afresh, reconsider controlling the integral solution of circuit. On the foundation that the Matlab that we mention in front emulates, drew lessons from the design thought of advanced digitlization welder, put forward the power source of arc solder inversion that the graph shows 10 times to digitlize control solution. Normal Align=center> pursues the block diagram of control system principle of power source of solder of arc of 10 digitlization inversion pursues 10 in complete digitlization welder can be divided for power and control two parts. Power part, three-phase 380V alternating current gets the dc of 540V through rectification and capacitance filter wave, circuit of inversion of course complete bridge, advocate inductance of wave of filter of transformer and bridge of commutate paying a margin, output, output the electric current of a need, voltage finally. Control is mixed with DSP partly odd a double engine system that the orgnaization becomes for core, the electric current in control and voltage pass changeover of sampling, A/D, read by DSP take feedback cost. The set-point of electric current, voltage is inputted by Control Panel, the course is only a machine C167CR is deferent give DSP (ADSP-2181) . DSP criterion basis of electric current, voltage give with feedback the quantity has operation, get corresponding IGBT guides a time, produce PWM pulse series. DSP chip is the ADSP-2181 of ADI, its control a program to have to load by IDMA mouth in the job, the program of to load stores at its memory mixes a course that attend respectively inside data memory, program to load is undertaken to low-lying location space by upland location space, finish the to load of 00000H finally. After program to load is finished, the program is begun to be carried out orderly by 00000H. The to load of the program by sheet piece machine C167CR control undertakes. Accordingly, in the double engine system that makes in C167CR and ADSP-2181, c167CR is advocate dominate chip (Host Micro-controller) . Control Panel and machine sending silk by respective sheet piece machine is alone control, the sheet in Control Panel piece machine the AT29C2051 that is ATMEL, this is a kind 8 20 sheet that make a base piece machine, piece go up the Flash that has 2Kbytes. The number of Control Panel is shown and key-press management is finished by 2 ICM7218A. Control of engine sending silk uses MCS80196KC. The MCS80196KC of the AT29C2051 of main control chip of face plate, machine sending silk and main control board C167CR is odd piece RS485 interface circuit is passed between machine bus line of local and serial control has news report. The face plate in the job is sent to C167CR solder the set-point of parameter, welder art phyletic, dot moves signal sending silk, signal trying gas to wait, and C167CR reads DSP value of feedback of extraction electricity, voltage and in soldering flow too, overheat, owe pressure wait for signal to convey to undertake indication to face plate. What the news report that sends filar machine control chip MCS-80C196KC and C167CR basically undertakes is C167CR send a statement to MCS80196KC, if send silk rate, send silk, stop to wait a moment. News report does not have directly between machine sending silk and face plate. From the point of the angle of the total management of welder, c167CR is core chip. In this solution, odd a machine C167CR is OK establish serial communication through RS232 interface and PC. The serial communication of C167CR has 2 effect, one is to solder the network management of craft and control, what another action undertakes controlling a process namely is online upgrade, it is the serial program to load that uses C167CR character actually (Boot Loader) the online Flash process designing that the function undertakes controlling a process. The sense of digitlization control technology of 3 conclusion research and power source of development arc solder is great. From the point of the craft effect of welder, because digitlization welder controls strategy to adjust agile, control precision is tall and control parameter stability is good, digitlization welder has better craft stability and better craft effect. In the meantime, the communication interface function with digitlization convenient welder was modern network production to provide good hardware basis. From the angle that arc solder craft studies, the technology control strategy that digitlizes welder to be executive innovation sex and implementation are muti_function offerred brand-new way. The online control program that digitlizes welder upgrades will produce effect, offer convenient, quick way to new control is carried out politicly. In light of the angle that develops from the technology, the opportunity that digitlizes welder research is mature. It is the development that theory of digital signal processing and computer technology pass nearly half century, perfect above all, the application that controls a technology for the digitlization of arc solder domain provided solid academic basis, accumulated valuable experience. It is digitlization next yuan of parts of an apparatus that control involves is phyletic and rich, all ready, and be obtained easily. The 3rd, abroad digitlizes the favorable response proof of the successful experience of welder and home, digitlization welder gained extensive favour. Accordingly, the research foreground that digitlizes welder is bright, the market that its did not come to also is sure more capacious. Equipment solders to develop to digitlization direction on international, the reality that promotes digitlization welder in great quantities to Chinese market has proved, to soldering position is occupied on the market, we must increase the research strength in this respect. Position also is occupied on the research in high-grade welder, production only, ethical welder of course of study revitalize and develop ability to have an outlet. CNC Milling CNC Machining