CN101977456A - Mobile wire induction heating controller - Google Patents
Mobile wire induction heating controller Download PDFInfo
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Abstract
The invention discloses a mobile wire induction heating controller, which comprises a CPU system control module, a data acquisition module, a data adapter module, a startup control module, a pulse forming module and a man-machine conversation module, wherein the CPU system control module consists of an INTEL80X86 processor, an INTEL80X87 floating point coprocessor, a DISKONCHIP electronic disc and a dynamic storage; the data acquisition module comprises an analogue value input unit, switching value input and output units and a counter triggering unit; the data adapter module consists of a direct current voltage acquisition unit, an analogue value acquisition adapting unit, switching value input and output adapting units and a synchronous signal conversion unit; the startup control module comprises a startup control logic unit and a pre-magnetization triggering unit; the digital pulse forming module comprises a synchronous signal shaping unit, a triggering angle calculation unit, a triggering pulse forming unit and a power amplification unit; and the man-machine conversation module comprises a liquid crystal display unit and a serial communication unit.
Description
Technical field
The present invention relates to advanced the manufacturing and automation control area, be specially a kind of mobile wire rod induction heating controller.
Background technology
Metal wire rods such as compressor wire, steel strand wire, aluminum cald steel wire power overhead network are when induction heating, need in the intermediate frequency power supply inductor, move, and require the movement velocity output different power of intermediate frequency induction heating power supply, be heated wire temperature and should be controlled at fluctuation in 380 ℃ ± 10 ℃ scopes according to wire rod.Quickening along with the mobile wire rod production line speed of service, can reach 110 meters/minute, (steel strand wire are divided into three layers by 19 steel wires and twist together the highest 1x19-28.6mm 1860Mpa in line footpath, in stranded process, release simultaneously and add tension force, just twisted wire tensile strength is 1860Mpa), the power maximum can reach 700KW.The domestic induction heating power that is applied in prestress wire mainly is made of resolution element at present, for example the PID adjuster is by resistance, electric capacity, operational amplifier is formed, and integrated degree is low, and controller is formed complicated, control precision is not high under friction speed, variations in temperature is big when acceleration or reduction of speed, can not control requirement, wire rod crudy instability by satisfied temperature.
Present mobile wire rod induction heating controller also adopts analogue device to constitute, and complex structure is adjusted inconvenience, and analogue device has dispersiveness in the long-time running process, can cause the variation of system's control precision; It is few that existing speed is followed the curve trace point, and when the wire rod high-speed cruising, temperature control precision is not high; Do not have temperature closed loop control and the too high supervision of temperature,, during variation of ambient temperature, cause very large deviation of actual heating-up temperature and design temperature easily when the line footpath of heating wire rod; Do not have acceleration compensation to regulate, when being heated wire rod raising speed or fall-back, variations in temperature is very big, and temperature phenomenon on the low side or higher appears in heating wire rod easily.
Summary of the invention
At the deficiencies in the prior art, the technical problem that quasi-solution of the present invention is determined is, a kind of mobile wire rod induction heating controller is provided, this controller is used for the hardening heat control of prestress wire stabilizing treatment technique, utilize inductive heating principle control intermediate frequency power supply heating steel strand wire, and the movement velocity control intermediate frequency induction heating power supply power output different according to wire rod, make the temperature of wire rod keep constant, improve the crudy of steel strand wire.This controller can carry out hardening heat control to different types of wire rod, has the control precision height, and reliable, control method is flexible, easy to operate characteristics such as simple.
The technical scheme that the present invention solves described controller technology problem is: design a kind of mobile wire rod induction heating controller, it is characterized in that this controller adopts digital modularized design, comprise that cpu system control module, data acquisition module, data adaptation module, starting control module, digit pulse form module and human-computer dialogue module; Described data comprise analog quantity and switching value;
Described cpu system control module is made of INTEL80X86 processor, INTEL80X87 floating-point coprocessor, DISKONCHIP electric board and dynamic memory, these constitute the unit and link to each other with address bus ADDRESS/DATA-BUS16 by 32 internal datas, and be connected to external bus PC104BUS17 by the conversion of data buffer BUFFER15, finish with other module, connect and meet the PC104 standard;
Described data acquisition module adopts to connect and meets the PC104 norm structure, comprises analog input unit, switching value input-output unit sum counter trigger element three parts, and every part is connected with data/address bus by the address; Described analog input unit is made up of the A/D conversion chip with 12 bit resolutions, maximum sample rate 200KHz, connects analog quantity by difference and forms 16 tunnel single-ended or 8 tunnel difference inputs; Described switching value input-output unit totally 24 tunnel adopts the TTL/CMOS compatible circuit; Described counter triggers unit is by 6 16, and 10MHz counting/timer is formed;
Described data adaptation module is by the direct voltage collecting unit, the analog acquisition adaptation unit, and switching value input and output adaptation unit and synchronizing signal converting unit are formed; Described analog acquisition adaptation unit is made up of linear isolating device, level shaping and match circuit; Described analog signals comprises the rate signal and the temperature signal of d. c. voltage signal, voltage of intermediate frequency signal, inlet wire current signal, mobile wire rod;
Described starting control module comprises starting control logic unit and premagnetization trigger element;
Described digit pulse forms module and adopts the two glitch triggers of digital phase shift able to programme, and this trigger comprises synchronous voltage signal modular converter, Programmable Logic Device CPLD module, programmable counter 82C54 module and pulse amplification module; Its connected mode is: at first through synchrotrans three-phase sine-wave is introduced the synchronous voltage signal modular converter, sine wave is converted into three-phase square wave; Three-phase square wave signal after will changing is again sent into Programmable Logic Device CPLD module, forms six tunnel pulse-triggered level; This triggering level is sent in the programmable counter 82C54 module start up command signals as trigger angle α, the control range of trigger angle α is 0-150 °, subtract counting through programmable counter 82C54 module stores register and calculate, finally export the pulse triggering signal of six tunnel 1 microsecond width; The pulse triggering signal of output is sent Programmable Logic Device CPLD module again back to and is carried out pulse stretching and combination, forms six tunnel two narrow trigger impulses; Isolate and amplification through the extra pulse amplification module at last, form the two narrow trigger impulses of phase shift;
Described human-computer dialogue module comprises liquid crystal display and serial communication unit.
Compared with prior art, the distinguishing feature of controller of the present invention is to adopt INTEL80X86 processor and INTEL80X87 data coprocessor (NPX) to be the control core, and the PC104 bus is the embedded industrial control computer that stack connects.Direct voltage, voltage of intermediate frequency, inlet wire current, speed, temperature continuous analog amount conversion of signals are discrete digital quantity signal.Utilize the real time computer control technology with the method for numerical computations to signal gather, conversion, integrated treatment.Controller has high performance temperature, power, voltage close loop regulating system.May command is heated wire temperature and changes in design temperature ± 2 degree scopes; Controller has high-performance speed following feature, according to the speed of service of different wire gage and wire rod, sets different power curves of output; Adjuster has high starting success rate, has premagnetization, precharge control logic; Has automatic start-stop, manual, auto-conversion function; Have perfect inlet wire current, voltage of intermediate frequency limitation function and overtemperature, phase shortage, misphase, lack of water, overvoltage, overcurrent, under-voltage protection function; Have the good man-machine interaction function, utilize big screen LCD, the user can adjust voluntarily and realize the setting of many group different size steel strand wire heating parameters.
After adopting controller of the present invention, system configuration is flexible, and is simple in structure, easy to adjust, owing to all adopt digital Control Technology, parameter tuning is convenient, and long-time running is stable; It is many that speed is followed the curve trace point, can accomplish unlimited a plurality of point in theory, when the wire rod high-speed cruising, and the temperature control precision height; Have temperature and close and change control and the too high supervision of temperature, when being heated wire rod and variation of ambient temperature, be heated wire temperature control well; Have acceleration compensation and regulate, when being heated wire rod raising speed or fall-back, variations in temperature is little, and it is constant to be heated wire temperature.Controller control method of the present invention is flexible, and it is constant to be heated wire temperature control, is difficult for broken string, the product to be processed steady quality, and output increases substantially.
Description of drawings
Fig. 1 moves the system configuration schematic diagram of a kind of embodiment of wire rod induction heating controller for the present invention;
Fig. 2 moves the cpu system control module schematic diagram of a kind of embodiment of wire rod induction heating controller for the present invention;
Fig. 3 moves the direct voltage input circuit structural representation of a kind of embodiment of wire rod induction heating controller for the present invention;
Fig. 4 moves the speed input circuit structural representation of a kind of embodiment of wire rod induction heating controller for the present invention;
Fig. 5 moves the temperature input circuit structural representation of a kind of embodiment of wire rod induction heating controller for the present invention;
Fig. 6 moves the switching value inputting and outputting circuit structure schematic diagram of a kind of embodiment of wire rod induction heating controller for the present invention;
Fig. 7 moves the two glitch trigger overall structure schematic diagrames of able to programme digital phase shift of a kind of embodiment of wire rod induction heating controller for the present invention;
Fig. 8 moves the synchronizing voltage Acquisition Circuit modular structure schematic diagram of the two glitch triggers of able to programme digital phase shift of a kind of embodiment of wire rod induction heating controller for the present invention;
Fig. 9 moves the field programmable logic circuit CPLD modular structure schematic diagram of the two glitch triggers of able to programme digital phase shift of a kind of embodiment of wire rod induction heating controller for the present invention;
Figure 10 moves the pulse amplification module structural representation of the two glitch triggers of able to programme digital phase shift of a kind of embodiment of wire rod induction heating controller for the present invention.
Embodiment
Further narrate the present invention below in conjunction with embodiment and accompanying drawing thereof:
The mobile wire rod induction heating controller of the present invention's design (is called for short controller, referring to Fig. 1), it is characterized in that this controller adopts digital modularized design, comprise that cpu system control module 1 (being called for short the CPU module), data acquisition module 2, data adaptation module 3, starting control module 4, digit pulse form module 5 and human-computer dialogue module 6, described data comprise analog quantity and switching value.
Described cpu system control module 1 (referring to Fig. 2) is made up of INTEL80X86 processor 11, INTEL80X87 floating-point or data coprocessor 12, DISKONCHIP electric board 14 and DRAM13 dynamic memory, forms structure and meets the PC104 standard.They are finished exchanges data by internal data bus with address bus ADDRESS/DATA-BUS16 and are connected, and are connected to external bus PC104BUS17 by the conversion of data buffer BUFFER15, finish and being connected of other module.Cpu system control module 1 is mainly finished data sampling and is calculated, the control of interrupt routine task management and system and adjusting.Described INTEL80X86 processor is enhancement mode 3.3V, 80486DXCPU, 33M-133MHz; The INTEL80X87 floating-point coprocessor is 80487, can handle 64 double-precision floating points and 80 extended precision floating datas; The PC104 standard specifically is characterized as: the ISA (PC of compact, PC/AT) bus structures, machinery and electrical code are provided, this structure is to optimize for the specific (special) requirements that embedded system is used, its bus-structured 104 holding wires are distributed on two Bussing connectors, having on the P1 connector has 40 signal pins on 64 signal pins, the P2 connector, this bus structures are called " PC/104 ".
Controller of the present invention adopts INTEL80X86 processor and INTEL80X87 data coprocessor (NPX), and whole control unit is formed structure and met the PC104 standard.The INTEL80X86 processor is rationally divided the boundary and the control hierarchy of control task by the real-time hierarchy of control of multitask, and distributes corresponding time resource for it, has improved the overall efficiency of software; The INTEL80X86 processor utilizes interrupt management system to execute the task and is divided into main program and interrupt routine: main program is finished the initialization of system as the main body of system, upper machine communication, liquid crystal display and fault logging function.Interrupt routine is divided into 1ms, 3ms and three grades of interrupt routines of 10ms from high to low by control hierarchy, wherein, with the 1ms interrupt routine is that priority is the highest, being provided with etc. of the calculating of finish manually, collection, filtering and the standardization of curve setting, temperature, acceleration simulation amount are followed in the initial given setting of automatic voltage, starting premagnetization, direct voltage, voltage of intermediate frequency protection, inlet wire current protection, speed-power, precharge logical function; 3ms interrupt routine priority level will be lower than the 1ms interrupt routine, and that mainly finishes speed follows functions such as curve setting, inlet wire current, voltage of intermediate frequency restriction, the adjusting of direct voltage constant voltage, temperature closed loop control; 10ms interrupt routine task priority is minimum, finishes the sending and fault comprehensive warning etc. of collection, filtering, switching value output signal of real-time less demanding switching value input signal.INTEL80X87 data coprocessor can be handled 64 double-precision floating points and 80 extended precision floating datas, can greatly improve accuracy, the rapidity of the computing of digital filtering, proportion integration differentiation (PID) correcting unit.Utilize INTEL80X87 data coprocessor to realize the cosine phase shift of control angle, it changes the output voltage of rectifier bridge into linear combination that controller is controlled voltage and rectifier bridge output current, and non-linear the obtaining of rectifier bridge proofreaied and correct, and alleviated the burden of controller.
Described data acquisition module 2 adopts the composition structure to meet the PC104 standard, comprises analog input unit, switching value input-output unit sum counter trigger element three parts, and every part is connected with data/address bus by the address; Described analog input unit is by having 12 bit resolutions, and the A/D conversion chip of maximum sample rate 200KHz is formed, and connects analog quantity by difference and can form 16 tunnel single-ended or 8 tunnel difference inputs; Analog input unit is mainly used to gather through several analog signalses such as the speed of the mobile wire rod in adaptive back and temperature, direct voltage, direct current, inlet wire current, voltage of intermediate frequency.Controller of the present invention is converted into discrete signal by the analog quantity conversion chip with direct voltage, inlet wire current, voltage of intermediate frequency, temperature, velocity simulate amount signal, with the method for numerical computations to signal gather, conversion, comprehensive and identification processing.Described switching value input-output unit totally 24 tunnel, adopt the TTL/CMOS compatible circuit, mainly finish the collection that several output signals such as hydraulic pressure protection, the several input signals of fault involution and premagnetization output, precharge output, starting failure output, fault output were folded, added in hand automatic switchover, stop signal, speed; Described counter triggers unit is by 6 16, and 10MHz counting/timer is formed, and finishes formation, pulse technique device clock setting, the setting of premagnetization pulse counter of three-phase trigger pulse respectively.
Described data adaptation module 3 is by direct voltage collecting unit 31, analog acquisition adaptation unit 32, and switching value input and output adaptation unit 33 and synchronizing signal converting unit 34 are formed; Described analog acquisition adaptation unit 32 is made up of linear isolating device, level shaping and match circuit; Described analog signals comprises direct voltage, voltage of intermediate frequency, inlet wire current, rate signal and temperature signal; Described direct voltage collecting unit 31 is obtained rectifier 7 output dc voltages by sampling resistor; By velocity transducer 9, temperature sensor 10, speed, temperature acquisition adaptation unit 32 are finished speed, degree selection of temperature signal; Switching value input and output adaptation unit 33 is finished the input and output of overall system control switching value; Synchronizing signal converting unit 34 changes into the square-wave signal that the rectifier and trigger pulse needs with synchronizing signal.The output (referring to Fig. 2) of three-phase fully-controlled rectifier 7 is directly taken from described direct voltage collection, insert Hall element 311HT+ through 50K resistance, the HT-terminal, voltage signal is converted to current signal, after Hall element 311 isolation, after utilizing sampling resistor 312 samplings, send into data acquisition module 2.
One of feature of controller of the present invention is that the analog quantity d. c. voltage signal adopts hall device to isolate, and utilizes Hall effect that major loop signal and control signal are isolated, and eliminates major loop because the interference that system with one power brings.The Hall element no-load voltage ratio is 1: 2.5, and when 10mA was imported on specified former limit, secondary output 25mA after sampling resistor (resistance 200 Ω) obtains sampled voltage, sent into data acquisition module 2.
The translational speed signal that described analog quantity rate signal is mobile wire rod, by velocity transducer 9 rate signal is converted into current signal, range is 0-20mA, send into Hall element 321, after isolating, be converted to voltage signal, and, finally send into data acquisition module 2 (referring to Fig. 4) through second-order filter circuit 322.
Described analog quantity temperature signal is the temperature signal of mobile wire rod, send into by temperature sensor, infrared thermometer 10, range is current mode 4-20mA (referring to Fig. 5), the bound that corresponding infrared thermometer 10 temperature of input signal show, isolation through linear optical coupler 323, by adaptation unit 324 output signal is converted to voltage signal, finally sends into data acquisition module 2.The temperature signal of controller of the present invention uses linear optical coupler to isolate, and carries out filtering after the isolation, will gather voltage then and send into data acquisition module 2.
Described inlet wire current is taken from the rectifier bridge AC side by current transformer; be used for the electric current restriction and protection of induction heating power; by 1000/5; 5/0.1 the two-stage current transformer is isolated; big current signal is converted to little current signal; use sampling or sample resistance to change current signal into voltage signal; the resistance of sample resistance is 150 Ω; sampling voltage is sent into controller through terminal; change AC signal into direct current signal by full-controlled rectifier, after send into data acquisition module 2 after the dividing potential drop.
Described voltage of intermediate frequency signal is taken from the two ends of inversion tank circuit inductance; be used for the voltage limit and the protection of induction heating power; isolate by the 1000V/17V intermediate frequency transformer; with inverter 8 output fly high-voltage signal change into can be adaptive voltage signal; introduce controller by terminal again; is d. c. voltage signal through rectification with single phase alternating current (A.C.) voltage signal transition, sends into data acquisition module 2 at last.
Described switching value input signal is formed (referring to Fig. 6) by the two-stage buffer circuit.The first order forms 331 by the AC220V AC relay in the rectifier cabinet, when input signal moves, exports active 24V contact point signal as partial input (referring to Fig. 6).The second level forms 332 by optocoupler in the controller, finishes the isolation of 24V/5V, and by sending end 333, output signal is sent into data acquisition module 2 (referring to Fig. 6).
Described switching value output signal is made of optical coupler and relay, controller is sent into switching value output unit receiving terminal 334 (referring to Fig. 6) after giving an order by data acquisition module 2, optical coupler 335 is finished switching value output signal 5V/24V level conversion and isolation (referring to Fig. 6), output signal control DC24V relay 336 after the conversion does not have source contact with relay and sends (referring to Fig. 6) by terminal.
Described starting control module 4 comprises starting control logic unit and premagnetization trigger element.For the success rate that guarantees to start in the steel strand wire production process, need be beforehand with the premagnetization of commutating circuit and the precharge of induction coil.There is complete logical circuit to control in order to finish these two needs of work.Rectifier cabinet 2C contactor behind the control power supply electrifying, the adhesive of inversion cabinet 3C contactor, the charging of precharge electric capacity.After precharge electric capacity is full of, send starting command by starting button, after controller receives starting command, send spike train (the Kg indicator light is lighted) through Kg and trigger premagnetization control controllable silicon 51KK, making whole premagnetization loop conducting is the reactor energy storage.After the premagnetization work several seconds, through sending charging capacitor discharge order, inversion cabinet 8MB triggers discharge control controllable silicon by controller, and charging capacitor discharges to the tank circuit.After segment time-delay, controller sends the excision order, disconnects through auxiliary relay interlock 2C contactor, 3C contactor, and locking Kg (the Kg indicator light extinguishes) and 8MB pulse, makes premagnetization controllable silicon 51KK, discharge loop controllable silicon 61KK stop conducting.After time-delay a period of time, controller is judged the whether starting of oscillation of the induction tank circuit, if starting of oscillation can continue to increase voltage, otherwise the rectification pilot angle is pulled to 150 ° of inverter modes, quotes starting failure simultaneously.If prepare starting once more, need press stop button, charging capacitor is charged once more to finish next prestarting preparation.
To be the The whole control logical circuit should be program control with former relay logic to the feature of controller of the present invention, 1, carry out timing by 1 pair of command operation time of cpu system control module, give an order by operation logic; 2, the premagnetization trigger element changes digital flip flop into by analog circuit, after at first the premagnetization order is sent, the 82C54 technology chip enable count register of data module subtracts counting, send a trigger impulse after reducing to zero, simultaneously counter register is reloaded, continue to carry out and to subtract the meter art, send trigger impulse after reducing to zero, up to premagnetization cease and desist order send after, stop pulse triggers.
Described digit pulse forms module 5 and adopts the two glitch triggers of digital phase shift able to programme, and this trigger comprises synchronous voltage signal modular converter 51, Programmable Logic Device CPLD module 52, programmable counter 82C54 module 53 and pulse amplification module 54 (referring to Fig. 7-10); Its connected mode is: at first through synchrotrans three-phase sine-wave is introduced synchronous voltage signal modular converter 51, sine wave is converted into three-phase square wave; Three-phase square wave signal after will changing is again sent into Programmable Logic Device CPLD module 52, forms six tunnel pulse-triggered level; This triggering level is sent in the programmable counter 82C54 module 53 start up command signals as trigger angle α, the control range of trigger angle α is 0-150 °, subtract counting through programmable counter 82C54 module 53 memory registers and calculate, finally export the pulse triggering signal of six tunnel 1 microsecond width; The pulse triggering signal of output is sent Programmable Logic Device CPLD module 52 again back to and is carried out pulse stretching and combination, forms six tunnel two narrow trigger impulses; Isolate and amplification through extra pulse amplification module 54 at last, form the two narrow trigger impulses of phase shift.
Described synchronizing voltage Acquisition Circuit module 51 (referring to Fig. 7,8) comprises synchrotrans 511, rc phase shifter circuit 512 and the shaping circuit 513 that is electrically connected successively.The operation principle and the process of synchronizing voltage Acquisition Circuit module 51 are: at first 380V three-phase primary voltage is isolated through synchrotrans 511, after three-phase inlet wire line voltage 380V is converted to 20V, give rc phase shifter circuit 512, rc phase shifter circuit 512 utilizes the characteristics of resistance-capacitance circuit phase lag, make the natural commutation point of the corresponding three-phase voltage of starting point of every phase voltage, enter shaping circuit 513 through after the phase shift; After shaping circuit 513 utilizes the anti-and amplitude limit of two diodes, again through with zero potential relatively after, three-phase sine-wave is become square-wave signal; But this square-wave signal phase place lags behind 30 ° of input signals, and output amplitude is 5V, and the natural commutation point of corresponding three-phase primary voltage, is sent to Programmable Logic Device CPLD module 52.
Described Programmable Logic Device CPLD module 52 (referring to Fig. 7,9) mainly is made of three partial logic unit, every part unit all adopts VHDL language to carry out Programming Design: pulse-triggered detecting unit 521, (pulse-triggered detecting unit 521 produces the triggering signal of pulse at zero point as programmable counter 82C54 module 53 separately, and is irrelevant with other two parts of this module for pulse expansion unit 522 and pulse combined unit 523.The broadening of the 1 μ s trigger impulse of being sent into by programmable counter 82C54 module 53 is finished in pulse expansion unit 522, and pulse combined unit 523 is sent in the pulse of broadening).The square-wave signal of synchronizing voltage Acquisition Circuit module 51 outputs is sent into the pulse-triggered detecting unit 521 of Programmable Logic Device CPLD module 52.By single-shot trigger circuit, detect the positive and negative zero crossing of ac voltage signal, and export the pulse at zero point in view of the above, the natural commutation point of corresponding three-phase voltage, programmable counter 82C54 module 53 is sent in this pulse at zero point.From the low trigger pulse width of programmable counter 82C54 module 53 outputs is the burst pulse of 1 μ s, and pulse expansion unit 522 is sent in this pulse.Deliver to the input end of clock of d type flip flop after the negate, the three-phase square wave signal is sent into the D end of d type flip flop, and when the burst pulse of 1 μ s triggered, the upset of d type flip flop output level formed the trigger impulse forward position.The pulse duration control signal is by timing signal for generating, and this signal is delivered to the reset terminal of d type flip flop, and this overturns d type flip flop output level again, thereby forms the narrow trigger impulse of list of six tunnel timing width.Single narrow trigger impulse is sent into pulse combined unit 523, and according to pulse sequence number, each pulse is that a thyristor of front is reissued pulse, can obtain six tunnel two burst pulses.Deliver to pulse amplification module 54 then.The internal core device of the Programmable Logic Device CPLD module 52 of embodiment is the EPM7128 chip, has 2500 in gate circuit, 128 of macrocells, 8 of logic array, 84 of external pins and encapsulation PLCC-84.
Described programmable counter 82C54 module 53 is used to produce trigger impulse, and programmable counter 82C54 module is converted to corresponding count pulse number to the angle of phase shifting angle, realizes time-delay by the hardware Timer.The accurate location that the design adopts three Timer of 82C54 to realize the trigger angle phase place.82C54 programmable timer chip calculates trigger angle and triggers phase place.82C54 programmable timer chip internal contains 3 16 Timer, triggers the external clock that clock adopts 1MHz, can realize 0.018 ° phase accuracy.Timer works in the hardware-initiated strobe pulse way of output, gate-control signal is by the pulse enable at zero point of Programmable Logic Device CPLD module 2 inputs, after treating that regularly counting finishes, export 1 μ s low level pulse, export Programmable Logic Device CPLD module 52 to, this low level pulse is the forward position of trigger impulse α.Utilize the latch function of timer, will calculate back data one-time write, and be preserved, write and fashionablely needn't judge the counting process; When no new data produces or computer when being busy with other task, the data in the latch can be used repeatedly; When counting the counter of to pack into automatically when finishing, begin counting when treating the arrival synchronously of counting next time.The inside of the programmable counter 82C54 module 53 of embodiment has three independently 16 digit counters, and six kinds of working mode selection can be according to the decimal system or the work of binary subtract counting, and counting clock is 8MHz.
Described pulse amplification module 54 (referring to Fig. 7,10) comprises light-coupled isolation unit 541, buffer unit 542 and the Pulse Power Magnification unit 543 that is linked in sequence.Isolate by light-coupled isolation unit 541 earlier through two burst pulses that Programmable Logic Device CPLD module 52 is sent into, send into buffer unit 542 and carry out signal adaptation, send into Pulse Power Magnification unit 543 again, the 6 tunnel two burst pulses that are used to finish 52 outputs of Programmable Logic Device CPLD module are proceeded power amplification, the pulse power of Programmable Logic Device CPLD module 52 pulse units output is less, need pass through light-coupled isolation unit 521, buffer unit 542 successively, just can be used for triggering thyristor behind the Pulse Power Magnification unit 543.Trigger impulse is entered by prime and further trigger controllable silicon in the module 54 after power amplifier tube amplifies.
Described human-computer dialogue module 6 comprises liquid crystal display and serial communication unit; Liquid crystal display is the part that the intelligent-induction heating controller is formed, and it makes things convenient for the user to carry out the observation of variable, the modification of parameter and the curing of Parameter File for the man-machine dialog interface that the user provides easy operating.Presentation Function mainly is made up of LCD and operation push-button, LCD has 12864R Chinese character image dot matrix, can show Chinese character and figure, built-in 8192 Chinese characters (16X16 dot matrix), 128 characters (8X16 dot matrix) and 64X256 dot matrix display random access memory (GDRAM).The serial communication unit can realize that host computer monitors controller parameter, online modification, the transmission of parameter and execute file.
The major cycle body of controller of the present invention is finished human-computer interaction function, utilize big screen LCD, the user can adjust voluntarily and realize the setting of many group different size steel strand wire heating parameters, show analog quantitys such as direct voltage, inlet wire current, voltage of intermediate frequency, the wire rod speed of service, wire temperature in real time, but display switch amount state, the user can also be set up and meet the display screen of oneself being accustomed to.By serial communication mode, upload, download and configuration file at the Windows interface, online demonstration service data, online modification and cure parameter etc.
The operation principle and the process of controller of the present invention are: at first respectively with high voltage or big current analog amount and digital quantity signal is isolated by data (analog quantity, switching value) adaptation module and decompression transformation for being receptible low-voltage of data acquisition module and little current signal.Wherein analog signals comprises direct voltage, voltage of intermediate frequency, inlet wire current, tachometric survey signal, temperature measurement signal.Wherein direct voltage collecting unit 31 is obtained rectifier 7 output dc voltages by sampling resistor; By velocity transducer 9, temperature sensor 10, speed, temperature acquisition adaptation unit 32 are finished speed, selection of temperature signal; Switching value input and output adaptation unit 33 is finished the input and output of overall system control switching value.The switching value input signal comprises hand automatic switchover, stop signal, speed stack, adds hydraulic pressure protection, fault involution etc.The switching value input signal is finished by the two-stage buffer circuit.The first order is made up of AC220V AC relay 331, when input signal moves, exports active 24V node signal as partial input.The second level is made up of interior optocoupler 332, finishes the isolation of 24V/5V, and by sending end 333, output signal is sent into data acquisition module 2.The switching value output signal comprises premagnetization, precharge, fault is quoted, equipment operation etc., the switching value output circuit is made of optical coupler and relay, and controller is sent into switching value output unit receiving terminal 334 (referring to Fig. 6) after giving an order by data acquisition module 2, and optical coupler 335 is finished switching value output signal 5V/24V level conversion and isolation (referring to Fig. 6), output signal control DC24V relay 336 after the conversion does not have source contact with relay and sends (referring to Fig. 6) by terminal; Synchronizing signal converting unit 34 changes into the square-wave signal that the rectifier and trigger pulse needs with synchronizing signal.By isolation, the step-down of data adaptation module 3, use stube cable with the analog quantity that collects, the switching value signal is sent to data acquisition module 2.It is digital quantity that data acquisition module 2 utilizes the A/D conversion chip that analog quantity is dispersed, and utilizes the switch acquisition chip to gather the switching value signal, and collected signal is sent into cpu system control module 1 by the PC104 bus;
Cpu system control module 1 with the signal that collects by analysis, calculate, judge, send starting command by data acquisition module, and deliver to starting control module 4 by stube cable.Utilize starting control module 4, rectifier cabinet 2C contactor behind the control power supply electrifying, the adhesive of inversion cabinet 3C contactor, the charging of precharge electric capacity.After precharge electric capacity is full of, send starting command by starting button, after controller receives starting command, send spike train (the Kg indicator light is lighted) through Kg and trigger premagnetization control controllable silicon 51KK, making whole premagnetization loop conducting is the reactor energy storage.After the premagnetization work several seconds, through sending charging capacitor discharge order, inversion cabinet 8MB triggers discharge control controllable silicon by controller, and charging capacitor discharges to the tank circuit.After segment time-delay, controller sends the excision order, disconnects through auxiliary relay interlock 2C contactor, 3C contactor, and locking Kg (the Kg indicator light extinguishes) and 8MB pulse, makes premagnetization controllable silicon 51KK, discharge loop controllable silicon 61KK stop conducting.After time-delay a period of time, controller is judged the whether starting of oscillation of the induction tank circuit, if starting of oscillation can continue to increase voltage, otherwise the rectification pilot angle is pulled to 150 ° of inverter modes, quotes starting failure simultaneously.If prepare starting once more, need press stop button, charging capacitor is charged once more to finish next prestarting preparation.
After starting successfully, cpu system control module 1 adopts automatic voltage to regulate, and control system adopts PID to regulate, and pid parameter can be adjusted respectively continuously, can be configured to forms such as P, PI, PD, has transient state and DC current gain inhibit feature.Satisfy the requirement of VD control precision, governing speed is fast, dynamic property good, wide accommodation.The controller operating speed is followed several curves of program setting, guarantees that power output is to being heated the constant control of wire temperature.Adopt temperature closed loop to regulate by way of compensation simultaneously, temperature closed loop is regulated controlling models and is used the pid algorithm after improving to control power output, the well requirement of satisfied temperature control.
Cpu system control module 1 compares according to inlet wire current signal of gathering and electric current limit setting value simultaneously, and voltage of intermediate frequency and voltage of intermediate frequency set point compare, and when inlet wire current numerical value reached current limit value, the demand limiter action was controlled inlet wire current.When inlet wire current numerical value reached the current protection maximum, the protection action is locking pulse simultaneously, stopped rectifier output.According to gather when the intermediate frequency voltage value reaches the voltage limit set point, voltage limitator moves, and voltage of intermediate frequency is controlled.When intermediate frequency voltage reached voltage protection setting maximum, the protection action is locking pulse simultaneously, stopped rectifier output.
As auxiliary computational unit, INTEL80X87 data coprocessor cooperates INTEL80X86 can handle 64 double-precision floating points and 80 extended precision floating datas, can greatly improve digital filtering, accuracy, the rapidity of the computing of proportion integration differentiation (PID) correcting unit, utilize INTEL80X87 data coprocessor to realize the cosine phase shift of control angle, it changes the output voltage of rectifier bridge into the linear combination of controller control voltage and rectifier bridge output current, non-linear the obtaining of rectifier bridge proofreaied and correct, and alleviated the burden of controller.
Last cpu system control module 1 will be calculated good pilot angle and send into the counter of data acquisition module 2 by the PC104 bus, be benchmark with the synchronous triggering signal, the generation digit pulse.Whole pulse-triggered unit is mainly formed by synchronizing signal, the calculating of trigger angle a, and pulse shaping, output and 3 links of power amplification are formed.
Controller of the present invention adopts powerful microprocessor, inner integrated timer can accurately be controlled the size of trigger angle α, realize that the digitlization phase shift triggers, utilize synchronizing signal converting unit 34, the rectification synchronous triggering signal that three synchronised primary voltages are converted to.By the synchrotrans in the rectifier cabinet three-phase inlet wire line voltage 380V is converted to 20V, send into controller through terminal, by phase shift, filtering, zero passage comparison circuit sinusoidal signal is converted to square-wave signal then,, forms final synchronous triggering signal through behind the monostable trigger.The formation of trigger angle need be used 3 counters, adopts the hardware trigger mode, the rising edge of counting synchronizing signal.Utilize counter internal lock storage, PID is calculated back data one-time write, and preserved, write and fashionablely needn't judge the counting process.When no new data produces or computer when being busy with other task, the data in the latch can be used repeatedly, and the counter of can packing into automatically when counting finishes treats to begin when counting arrives synchronously next time counting.The thyristor gate control impuls is utilized counter to produce by CPU and was handled through CPLD, distributes automatically by phase sequence, forms two burst pulses of 6 tunnel complementations.Pulse duration can be by software set, and the output pulse power of gating pulse unit is less, needs just can be used for triggering thyristor through amplifying.The amplification task is finished by the pulse amplifier unit.Its output pulse is sent by controller terminal G1-K1, G2-K2, G3-K3, G4-K4, G5-K5, G6-K6 after the pulse transformer isolation, directly triggers thyristor.When pulse-triggered just often, six working properly lighting of LED light of front panel K1-K6.With locking pulse, six LED light of K1-K6 are extinguished during fault.
Human-computer dialogue module 6 is directly introduced signal cpu system control module 1 by parallel interface, finishes the demonstration and the modification of parameter.The man-machine dialog interface of easy operating is provided, has made things convenient for the user to carry out the observation of variable, the modification of parameter and the curing of Parameter File.Presentation Function mainly is made up of LCD and operation push-button, LCD has 12864R Chinese character image dot matrix, can show Chinese character and figure, built-in 8192 Chinese characters (16X16 dot matrix), 128 characters (8X16 dot matrix) and 64X256 dot matrix display random access memory (GDRAM).The serial communication unit can realize that host computer monitors controller parameter, online modification, the transmission of parameter and execute file.Utilize big screen LCD, the user can adjust voluntarily and realize the setting of many group different size steel strand wire heating parameters, show analog quantitys such as direct voltage, inlet wire current, voltage of intermediate frequency, the wire rod speed of service, wire temperature in real time, but and display switch amount state, the user can also be set up and meet the display screen of oneself being accustomed to.By serial communication mode, upload, download and configuration file at the Windows interface, online demonstration service data, online modification and cure parameter etc.
Claims (10)
1. mobile wire rod induction heating controller, it is characterized in that this controller adopts the digital modularized design of DCR, comprise that cpu system control module, data acquisition module, data adaptation module, starting control module, digit pulse form module and human-computer dialogue module, described data comprise analog quantity and switching value;
Described cpu system control module is made of INTEL80X86 processor, INTEL80X87 floating-point coprocessor, DISKONCHIP electric board and dynamic memory, these constitute the unit and link to each other with address bus ADDRESS/DATA-BUS16 by 32 internal datas, and be connected to external bus PC104BUS17 by the conversion of data buffer BUFFER15, finish with other module, connect and meet the PC104 standard;
Described data acquisition module adopts to connect and meets the PC104 norm structure, comprises analog input unit, switching value input-output unit sum counter trigger element three parts, and every part is connected with data/address bus by the address; Described analog input unit is made up of the A/D conversion chip with 12 bit resolutions, maximum sample rate 200KHz, connects analog quantity by difference and forms 16 tunnel single-ended or 8 tunnel difference inputs; Described switching value input-output unit totally 24 tunnel adopts the TTL/CMOS compatible circuit; Described counter triggers unit is by 6 16, and 10MHz counting/timer is formed;
Described data adaptation module is by the direct voltage collecting unit, the analog acquisition adaptation unit, and switching value input and output adaptation unit and synchronizing signal converting unit are formed; Described analog acquisition adaptation unit is made up of linear isolating device, level shaping and match circuit; Described analog signals comprises the rate signal and the temperature signal of d. c. voltage signal, voltage of intermediate frequency signal, inlet wire current signal, mobile wire rod;
Described starting control module comprises starting control logic unit and premagnetization trigger element;
Described digit pulse forms module and adopts the two glitch triggers of digital phase shift able to programme, and this trigger comprises synchronous voltage signal modular converter, Programmable Logic Device CPLD module, programmable counter 82C54 module and pulse amplification module; Its connected mode is: at first through synchrotrans three-phase sine-wave is introduced the synchronous voltage signal modular converter, sine wave is converted into three-phase square wave; Three-phase square wave signal after will changing is again sent into Programmable Logic Device CPLD module, forms six tunnel pulse-triggered level; This triggering level is sent in the programmable counter 82C54 module start up command signals as trigger angle α, the control range of trigger angle α is 0-150 °, subtract counting through programmable counter 82C54 module stores register and calculate, finally export the pulse triggering signal of six tunnel 1 microsecond width; The pulse triggering signal of output is sent Programmable Logic Device CPLD module again back to and is carried out pulse stretching and combination, forms six tunnel two narrow trigger impulses; Isolate and amplification through the extra pulse amplification module at last, form the two narrow trigger impulses of phase shift;
Described human-computer dialogue module comprises liquid crystal display and serial communication unit.
2. mobile wire rod induction heating controller according to claim 1, it is characterized in that the rate signal that described analog quantity moves wire rod is converted into current signal by velocity transducer with rate signal, range is 0-20mA, send into Hall element, after isolating, be converted to voltage signal, and, finally send into data acquisition module through second-order filter circuit.
3. mobile wire rod induction heating controller according to claim 1, it is characterized in that described analog quantity temperature signal sent into by temperature sensor, infrared thermometer, range is current mode 4-20mA, the bound that the corresponding infrared thermometer temperature of input signal shows, isolation through linear optical coupler, by adaptation unit output signal is converted to voltage signal, finally sends into data acquisition module.
4. mobile wire rod induction heating controller according to claim 1, it is characterized in that described analog quantity d. c. voltage signal adopts hall device to isolate, the no-load voltage ratio of Hall element is 1: 2.5, during specified former limit input 10mA, secondary output 25mA, sampling resistor through resistance 200 Ω obtains sampled voltage, sends into data acquisition module.
5. mobile wire rod induction heating controller according to claim 1, it is characterized in that described analog quantity inlet wire current signal takes from the rectifier bridge AC side by current transformer, by 1000/5,5/0.1 the two-stage current transformer is isolated, big current signal is converted to little current signal, use the sampling resistor of resistance 150 Ω to change current signal into voltage signal, sampled voltage is sent into controller through terminal, change AC signal into direct current signal by full-controlled rectifier, after after the dividing potential drop, send into data acquisition module.
6. mobile wire rod induction heating controller according to claim 1 is characterized in that described INTEL80X86 processor is enhancement mode 3.3V, 80486DXCPU, 33M-133MHz; The INTEL80X87 floating-point coprocessor is 80487.
7. mobile wire rod induction heating controller according to claim 1, the inside that it is characterized in that described programmable counter 82C54 module has three independently 16 digit counters, six kinds of working mode selection can be according to the decimal system or the work of binary subtract counting, and counting clock is 8MHz.
8. mobile wire rod induction heating controller according to claim 1, the internal core device that it is characterized in that described Programmable Logic Device CPLD module is the EPM7128 chip, has 2500 in gate circuit, 128 of macrocells, 8 of logic array, 84 of external pins and encapsulation PLCC-84.
9. mobile wire rod induction heating controller according to claim 1, it is characterized in that described INTEL80X86 processor utilizes interrupt management system to execute the task and is divided into main program and interrupt routine: main program is finished the initialization of system, upper machine communication, liquid crystal display and fault logging function; Interrupt routine is divided into 1ms, 3ms and three grades of interrupt routines of 10ms from high to low by control hierarchy, wherein, mainly finishes the calculating of collection, filtering and the standardization of direct voltage, inlet wire current, speed, temperature, acceleration simulation amount with the 1ms interrupt routine; The 3ms interrupt routine mainly finishes the restriction of following curve setting, inlet wire current, voltage of intermediate frequency of speed and protection, direct voltage constant voltage are regulated, the temperature closed loop controlled function; The 10ms interrupt routine finish real-time less demanding switching value input signal collection, filtering, switching value output signal send and fault comprehensive is reported to the police.
10. mobile wire rod induction heating controller according to claim 1 is characterized in that describedly, and INTEL80X87 data coprocessor has 64 double-precision floating points and 80 extended precision floating datas, realizes the cosine phase shift of control angle.
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