CN209689408U - A kind of high temperature furnace control device - Google Patents

Abstract

The utility model discloses a kind of high temperature furnace control devices, device include open/stop latching circuit, phase-shift voltage regulating module, transformer, current transducer, temperature-control heat couple, high temperature furnace controller, touch screen control platform, high temperature furnace controller includes, furnace temperature signal conditioning circuit, A/D1, A/D2, D/A, D/A output driver, open/stop control interface, CPU, communication interface, temperature rise inspecting interface, current transducer real-time detection heated current is connected by high temperature furnace controller, voltage regulating module is shifted in regulation, realize the reasonable temperature control of high temperature furnace, whole device and method have the characteristics that temperature control is safe and reliable reasonable.

Description

A kind of high temperature furnace control device

Technical field

The utility model relates to automatic temperature controlling technical field, specially a kind of running protection of pyrometer couple assay furnace Control device.

Background technique

Pyrometer couple assay furnace (hereinafter referred to as " high temperature furnace ") be mainly used as calibrating Type B thermocouple, tungsten-rhenium thermocouple and The temperature source of other pyrometer couples, operating temperature range are usually that (1100~1500) are DEG C even higher.Production is high at present The main material of warm stove heating body has Pt-Rh wire and with two kind of Si-Mo rod of the production of molybdenum disilicide material, they all have cold The characteristics of state resistance is small, positive temperature coefficient, the calandria entirety cold-state resistance of high temperature furnace is usually in (0.1~1) Ω quantity Grade, therefore the power supply of high temperature furnace generally can not need to carry out decompression power supply by transformer, i.e., low electricity directly with 220V power supply power supply Pressure, high current power supply, such as using Si-Mo rod as the high temperature furnace of calandria, maximum heat current is usually 60A or so.Mesh Before, the control of high temperature furnace there are the problem of mainly have:

1. power up: high temperature furnace is generally in cold conditions (room temperature) when starting powers on, and high temperature furnace calandria at this time is cold State resistance usually in (0.1~1) the Ω order of magnitude, is powered, heated current is still well over high temperature even by step-down transformer The allowable upper limit value of stove heating body surface loading, or more than the load-bearing capacity of power supply line, need to be adjusted to very low power supply at this time Voltage, common starting method are, first by adjustable power-supplying circuit (as adjusted auto-transformer or silicon-controlled phase shifting angle) High temperature furnace supply current is adjusted to minimum, heated current is then gradually increased by vernier knob, until the volume for the furnace that reaches a high temperature Determine heated current.When necessary, as supplementary means, usable transformer tapping makes supply voltage be classified up-regulation from deep low gear.

No matter above-mentioned control passes through manual adjustment or uses analog circuit auxiliary adjustment, is both needed to manual intervention, cumbersome.

2. temperature-rise period: high temperature furnace from the entire temperature-rise period that cold conditions rises to 1100 DEG C or so, the resistance of calandria with The raising of temperature and significantly increase, heated current reduces, and heating rate also reduces therewith, supplies if continuing to use too low voltage Electricity will limit the normal heating of high temperature furnace again, and needs are constantly appropriate again at this time increases supply voltage, to guarantee normally heating speed Rate, but supply voltage again cannot be too high, to prevent calandria to be burned.

3. furnace shutting down process: burner hearth may cause with fast speed cooling and be in high temperature in furnace in high temperature furnace temperature-fall period Refractory part, material lead to deformation, crackle equivalent damage because of rapid cooling.

Summary of the invention

The utility model provides a kind of high temperature furnace control device, can be effectively realized by the device and carry out temperature to high temperature furnace Degree controls and multiple protective control, keeps its entire temperature control process reasonable, reliable, safe.

In order to achieve the above objectives, the technical solution adopted in the utility model:

A kind of high temperature furnace control device, it includes opening/stopping latching circuit, phase-shift voltage regulating module, transformer, electric current pick-up Device, temperature-control heat couple, high temperature furnace controller, console open/stop latching circuit, phase-shift voltage regulating module, transformer, electric current pick-up Device is successively set on the heating power supply inlet wire of high temperature furnace；

The high temperature furnace controller include furnace temperature signal conditioning circuit, A/D1, A/D2, D/A, D/A output driver, Control interface, CPU, communication interface are opened/stop, the working end of the temperature-control heat couple is placed in effective operation temperature area of high temperature furnace, The reference end of temperature-control heat couple is connected to the input terminal of furnace temperature signal conditioning circuit through extension wire, furnace temperature signal conditioning circuit Output end is connected to the input terminal of the A/D1, the heating that the input terminal of the current transducer is connected to high temperature furnace power into Line, the output end of the current transducer are connected to the input terminal of the A/D2, and the output end of the D/A is connected to the D/A The input terminal of output driver, the output end of the D/A output driver are connected to the input terminal of the phase-shift voltage regulating module, The output end of the phase-shift voltage regulating module is connected to the primary circuit of the transformer, the output end for opening/stopping control interface It is connected to the input terminal for opening/stopping latching circuit；

The output end of the A/D1, the output end of A/D2, the input terminal of D/A, the output end, logical that opens/stop control interface The output end of communication interface is all connected to CPU, and the communication interface is connected to console by RS-232 mouthfuls.

The thermoelectrical potential signal of temperature-control heat couple output represents the Current Temperatures of the effective workspace of high temperature furnace, furnace temperature signal condition Circuit, A/D1, temperature scale transformation is carried out through software, obtains furnace temperature current value.Furthermore the furnace temperature current value of high temperature furnace can also pass through mark Quasi- thermocouple substitution temperature-control heat couple measures, or is directly passed down and obtained by RS-485 communication by host computer.

High temperature furnace controller further includes temperature rise inspecting interface, and the input terminal of temperature rise inspecting interface connects more surface temperatures Meter, the output end of the temperature rise inspecting interface are connect with CPU, and it is easy that the temperature-sensing probe of the land surface pyrometer is separately mounted on The low-voltage, high-current electric terminal position of fever.

CPU in the high temperature furnace controller, in the present embodiment using 32 single-chip microcontroller LCP23 ×× series；It is described Phase-shift voltage regulating module select have input, output isolation features silicon-controlled phase-shift voltage regulating module, input be usually (0~ 10) V.

A kind of temperature control method using above-mentioned high temperature furnace control device, in the entire temperature regulation and control process of high temperature furnace In, real-time monitoring is carried out to high temperature furnace heated current, the control of high temperature furnace controller shifts to voltage regulating module regulation transformer, constitutes electricity Flow limiting element, it is ensured that high temperature furnace heated current is no more than the heated current upper limit of setting.

The input terminal of current transducer is connected to the heating power supply inlet wire of high temperature furnace, and the high temperature furnace controller passes through A/D2 The output signal for receiving current transducer is simultaneously scaled high temperature furnace heated current current value, and within the high temperature furnace heated current that sets The upper limit as heated current setting value, the two collectively as heated current limit algorithm input, it is defeated by current limit algorithm Voltage regulating module is shifted in control out, controls transformer, is realized and is limited output to heated current.

The heated current limitation, which adjusts algorithm, can adjust algorithm by PI algorithm or other closed loops, in order to realize heating Current limit function.

In the land surface pyrometer that temperature rise inspecting interface is connected, there is one to be used to measure environment temperature, other surface temperatures Meter is separately mounted on transformer secondary output and exports into the low-voltage and high-current circuit of high temperature stove heating body input terminal, Yi Fare Monitored electric terminal position.

In order to which the temperature rise to each monitoring position carries out tour inspection, the temperature of environment temperature and each monitoring position is patrolled Measurement is returned, and using the difference of the temperature at each monitoring position and environment temperature as the temperature rise at corresponding monitoring position.High temperature furnace control Device will be issued by console, communication port and acoustic and light information and be alarmed, if electric once discovery has more than the electric terminal of normal temperature rise Gas contact temperature rise meets or exceeds protection temperature rise, and the high temperature furnace controller is by opening, and/stopping control interface control to open/stops self-locking electricity Road cuts off rapidly main current supply circuit, implements electric terminal overtemperature prote, avoids the further expansion of failure.

The high temperature furnace controller is provided with to be opened with described/stop latching circuit connect open/stops control interface, to control The remote control of the main current supply circuit of high temperature furnace is opened/is stopped and automatically powers off.Self-locking electricity is opened/stopped in traditional start-stop button and A.C. contactor On the basis of road, start-stop button control line is connected to open/stop control interface so that it is described open/stop control be extended to and can lead to CPU control is crossed, CPU simulates the start button and stop button manually pressed on console by controlling two relays respectively Electrical effects, realize that the remote control of main current supply circuit is opened/stopped and automatically powers off, and then communication port can be passed through and realize the main power supply of high temperature furnace The remote control start and stop in circuit.

The high temperature furnace controller externally provides RS-232 and RS-485 communication function through communication interface, and two communication ports are Isolated port is simultaneously operable.Described RS-232 mouthfuls be used for station touch screen operation, described RS-485 mouthfuls can be used for it is upper The communication of position machine carries out longer-distance control to high temperature furnace or networking controls.

The utility model has the following beneficial effects:

High temperature furnace controller in the device has measurement of furnace temperature and furnace temperature regulatory function, and the specificity of adjusting is stronger；Institute Current signal can effectively be acquired by stating thermocurrent limitation function, controller monitoring avoid high temperature furnace because heated current it is excessive caused by Damage, the safe and reliable work of high temperature furnace is effectively ensured；Pass through the inspection function to main current supply circuit related electric contact temperature rise Can, it can effectively avoid the expansion of electric fault, improve the reliability and safety of the work of high temperature furnace electrical control equipment；It is described The RS-485 mouthfuls of communications that can be used for host computer carry out longer-distance control to high temperature furnace or networking control.

Detailed description of the invention

Fig. 1 is the utility model principle frame diagram.

Fig. 1 explanation: 1-open/stop latching circuit；2-phase-shift voltage regulating modules；3-transformers；4-current transducers；5— High temperature furnace；6-high temperature furnace calandrias；7-temperature-control heat couples；9-furnace temperature signal conditioning circuits；10—A/D1；11—A/D2； 12—D/A；13-D/A output drivers；14-open/stop control interface；15—CPU；16-communication interfaces；17-temperature rises are patrolled Examine interface；18-high temperature furnace controllers；19-land surface pyrometers, 20-consoles.

Fig. 2 is high temperature furnace controller start and stop latching circuit schematic diagram；

Fig. 3 is high temperature furnace temperature control method temperature control Principles of Regulation figure；

Fig. 4 is that current limit link and electric current raising speed limit schematic diagram in high temperature furnace temperature control method.

Specific embodiment

A kind of high temperature furnace control device is shown in Fig. 1, it includes opening/stopping latching circuit 1, phase-shift voltage regulating module 2, transformer 3, electricity Flow transmitter 4, temperature-control heat couple 7, high temperature furnace controller 18, land surface pyrometer 19, touch screen control platform 20.The high temperature furnace control Device processed include furnace temperature signal conditioning circuit 9, A/D1 10, A/D2 11, D/A 12, D/A output driver 13, open/stop control connect Mouth 14, CPU 15, communication interface 16, temperature rise inspecting interface 17.The temperature-control heat couple 7 is Type B thermocouple, and working end is placed in In effective operation temperature area of high temperature furnace 5, reference end is connected to the input terminal of furnace temperature signal conditioning circuit 9 through extension wire, described The input terminal (i.e. annular core passes through electromagnetic coupling) of current transducer 4 is connected to the heating power supply inlet wire of high temperature furnace 5, described The output end of current transducer 4 is connected to the input terminal of the A/D2 11, and the output end of the D/A 12 is connected to the D/A The input terminal of output driver 13, the output end of the D/A output driver 13 are connected to the input of the phase-shift voltage regulating module 2 End, the output end of the phase-shift voltage regulating module 2 is connected to the primary circuit of the transformer 3, described to open/stop control interface 14 Output end be connected to the input terminal for opening/stopping latching circuit 1, the output end of the temperature rise inspecting interface 17 connects more tables Surface thermometer 19, it is electrical that the temperature-sensing probe of the land surface pyrometer 19 is separately mounted on the related low-voltage, high-current for being easy fever Contact position.The output of the A/D1 defeated outlet, the output end of A/D2 11, the input terminal of D/A 12, temperature rise inspecting interface 17 Hold, the output end of the input terminal that opens/stop control interface 14, communication interface 16 is all connected to CPU15, the communication interface 16 RS-232 mouthfuls are connected to the touch screen control platform 20.

The software of the high temperature furnace controller 18 uses real-time multi-task operating system, and high-precision measurement of furnace temperature, furnace is arranged Warm PID adjusts, heated current monitoring, heated current limitation, power on delay startup (current rate limitation), cooling protection, remote control are opened Stop, RS-232 and RS-485 communication etc. real-time tasks or functional module.

Each section of the high temperature furnace control device is introduced respectively by concrete function or adjusting controlling unit below:

1. opening ,/stop self-locking function: the high temperature furnace controller 18 in Fig. 1 includes and opens/stops opening/stopping for the connection of latching circuit 1 Control interface 14, the remote control to control the main current supply circuit of high temperature furnace 5 are opened/are stopped, and the more detailed working principle in the part is shown in Fig. 2. In Fig. 2, A.C. contactor J, normally opened button S3, normally closed button S4 etc. constitute traditional, based on start button and stop button Electrical equipment power supply opens/stops self-locking control circuit, and wherein S3 is start button, and S4 is stop button.To make this from lock control electricity Road can be controlled by high temperature furnace controller 18, to carry out timely power-off protection and by RS-232 or RS-485 communication port Start and stop are remotely controlled, simulate normally opened button and normally closed button respectively with two relays J1, J2 in high temperature furnace controller, In, normally opened button is simulated using the normally opened contact of relay J1, it is in parallel with S3；It is simulated using the normally-closed contact of relay J2 normally closed Button is connected with S4, applies the pulse that the retention time is (0.3~1.0) s to the relay coil of J1, J2 respectively by software Driving can simulate starting, the stop button movement of S3, S4 respectively.If host computer sends starting or stops order, high temperature furnace After controller receives order, pressing, lifting for the manual actuation of button S3 or stop button S4 on J1 or J2 simulation console is controlled Movement is played, have and opens/stop manually identical operating effect.Opening/stopping in J1, J2 and related software function constitution map 1 controls Interface 14.

In addition, the high temperature furnace controller 18 by monitor the self-locking circuit A.C. contactor J auxiliary contact (J's 1,2 terminal) open and-shut mode, real-time monitoring is carried out to the whether upper electricity operation of high temperature furnace.When CPU monitor contactor auxiliary contact from Off-state becomes attracting state, and high temperature furnace controller judges that system is in power up, is initialized and starts related appoint It works work, heat driven signal slowly rises since 0V, generates the effect for powering on delay startup, and system enters power-up state.If CPU monitors that contactor auxiliary contact are in an off state, then judges that high temperature furnace is in off-position, then inter-related task only carries out Measurement is controlled without adjusting.

2. phase-shift voltage regulating module: the phase-shift voltage regulating module 2 in Fig. 1 should be selected with input, export the controllable of isolation features Silicon phase-shift voltage regulating module, input are usually (0~10) V, and output-current rating is according to the difference of high temperature furnace calandria, according to institute The sufficiently reserved electric current surplus of the phase-shift voltage regulating module declaration book of choosing, generally selects output-current rating range in (40~100) A, Furthermore to reduce the electric current for flowing through module, and the high voltage arc phenomenon incuded by current break is eliminated, by the phase-shift voltage regulating The primary circuit of transformer 3 is arranged in module 2.

3. transformer: the transformer 3 in Fig. 1 is responsible for being depressured alternating current 220V or 380V Alternating Current Power Supply, to guarantee to add Thermoelectric generator voltage and 6 Proper Match of high temperature furnace calandria make phase-shift voltage regulating module 2 have reasonable dynamic regulation range, and are height Warm stove heating body 6 provides comparatively safe power supply environment.The transformer 3 is power-type transformer, and capacity is maximum by high temperature furnace Power designs, usually not less than 3kVA, it is proposed that use primary and secondary isolated form transformer, secondary voltage usually selects 80V or so, secondary Grade is not necessarily to centre tap, uses auto-transformer if volume is reduced, then must strictly differentiate fire during installing and using Line, zero curve guarantee that zero line side accesses high temperature furnace, it is ensured that Electrical Safety.

4. current transducer: the secondary of transformer 3, i.e. high temperature furnace current supply circuit is arranged in the current transducer 4 in Fig. 1 In, the current transducer 4 is conventional punching structure current transducer, even if the heating power supply inlet wire of high temperature furnace 5 passes through The annular core of current transducer 4, pass through electromagnetic coupling incude high temperature furnace 5(high temperature furnace calandria 6) heated current, the electricity The output end of flow transmitter 4 is connected with 11 input terminal of A/D2 in high temperature furnace controller 18.The current transducer 4 is responsible for real When acquire high temperature furnace heated current, control and protection to high temperature furnace are played the role of vital, should carefully check before use Technical parameter guarantees that input parameter of the input with output parameter respectively at high temperature furnace and AD2 correctly matches.

5. high temperature furnace controller: the CPU 15 in the high temperature furnace controller 18 uses 32 monolithics in the present embodiment Machine LCP23 ×× series.The high temperature furnace controller 18 is separately installed in special-purpose metal shielding box.The high temperature furnace controller It is the core of the utility model.

6. furnace temperature signal conditioning circuit: furnace temperature signal conditioning circuit 9 in Fig. 1 include disconnected even protection circuit, filter, Low noise dc amplifier etc..

It is disconnected occasionally to protect circuit (referring to Fig. 3) to temperature-control heat couple 7(or standard couple) the small continuous current of load, specifically Example is the resistance that 3M Ω or so is bridged between the input anode and 12V DC power supply of signal conditioning circuit, to detect The closed state of measurement of furnace temperature circuit high temperature furnace controller external circuit, if temperature-control heat couple 7(or standard couple) and its Connecting wire constitutes normal closed circuit, then influence of the Weak current to measured temperature is converted into temperature, only zero In the point several years, can ignore, if temperature-control heat couple 7(or standard couple) open circuit or temperature measurement circuit open circuit, AD1 measures Outrange d. c. voltage signal, external temperature measuring circuit open circuit is determined by software, referred to as " is broken even ", thus the disconnected even guarantor of starting Protective function is forced for heated current to be set to zero while alarm, or forces to cut off main current supply circuit.

Since the power supply of high temperature furnace uses phase-shifting trigger scheme, and controlled for high current, power frequency (50Hz) in current supply circuit The higher hamonic wave of power supply is the direct current of the 10mV order of magnitude by the temperature-control heat couple 7 furnace temperature signal collected than more serious Voltage signal, the signal may be submerged in interference noise, it is necessary to be taken effective measures and be extracted, therefore use has Source low-pass filter carries out prime filtering, and carries out digital filtering by software.

When necessary, in order to which the electric potential signal and the input range of AD1 that make temperature-control heat couple match, in furnace temperature signal condition Low noise dc amplifier is arranged in circuit, and amplifier should serve as the direct current amplification using the amplifier of low noise, low drifting characteristic Device.

7. A/D1: the AD1 10 in Fig. 1 is mainly responsible for the high-precision A to furnace temperature signal/D conversion should using ADS1232 Effective Measurement Resolution power of the integrated converter with 23.5bit, noise programmable gain control (PGA), 100db or more The functions such as common-mode rejection ratio, double passage differential input, internal temperature sensor compensation, are fully able to be competent at Type B thermocouple Pyrometer couple measurement, temperature measurement resolution reach 0.01 DEG C.

8. A/D2: the A/D2 11 in Fig. 1 receives the output signal from current transducer 4, is used for high temperature stove heating Current transformation is digital quantity, as heated current limitation, the input parameter for the associated adjustments controlling unit such as power on delay startup, is not necessarily to Very high A/D conversion resolution, therefore use a channel of AD inside the 10bit of single-chip microcontroller.

9. D/A: the optional DAC8311 of the D/A 12 is 14 DAC, using I²C bus, the connection with single-chip microcontroller is very Simply, output end is connect through D/A output driver 13 with the input terminal of phase-shift voltage regulating module 2, the phase-shift voltage regulating module 2 Output end connect with 3 primary circuit of transformer by tandem.The input terminal of the D/A 12 can regard that this is practical as It is multiple in novel adjust, the point of controlling unit, and the composition such as voltage regulating module 2, high temperature furnace calandria 6 it is above-mentioned it is multiple adjust, Control the public executing agency of closed loop.

10 communication interfaces: in the present embodiment, the communication interface 16 externally provides RS-232 and RS-485 mouthfuls, wherein RS-232 mouthfuls as the communication interface between high temperature furnace controller and touch screen control platform, and RS-485 mouthfuls can be used for and host computer (if any) communication, and can be remotely controlled in distance apart from each other.RS-232 mouthfuls and RS-485 mouthfuls are that isolation is logical Mouth is interrogated, there is stronger anti-interference ability.

The more detailed functional block diagram of furnace temperature PID regulating loop is shown in Fig. 3, and wherein dotted portion belongs to other adjustings.

The output of the AD1 10 is scaled the temperature magnitude for meeting international 90 temperature scales, works as furnace temperature through scale conversion Preceding value PV, the input adjusted with the furnace temperature setting value SV given by console or RS-485 communication port collectively as furnace temperature PID, Task execution furnace temperature PID is adjusted by the furnace temperature in software and adjusts algorithm, and the output of the furnace temperature governing loop is furnace temperature PID tune Section amount, i.e. Out1 in Fig. 3.

The increment output Δ Out1 that the furnace temperature PID is adjusted is that furnace temperature PID adjusts output quantity, adjusts output Out1 at one Adjustment amount during regulating cycle Δ t.Out1 does not directly drive the D/A 12, but the output with heated current limitation Out2, output Out3, the output Out4 of cooling protection of the limitation of heated current raising speed etc. are sent into output synthesis shown in Fig. 3 jointly Device (by software realization) after synthesizing Out, is converted to analog quantity by the D/A 12, and through D/A output driver 13, most End form drives phase-shift voltage regulating module at driving signal, achievees the purpose that adjust high temperature furnace supply voltage and heated current.

In order to which real-time measurement passes through the heated current of high temperature furnace calandria 6, the power supply inlet wire for being connected to the calandria 6 is worn The annular core of overcurrent transmitter 4, the current transducer 4 is exported by links such as electromagnetic coupling, amplifications to be added with high temperature furnace Thermocurrent (0~5) V output voltage signal in a linear relationship, the voltage signal are connected to the A/D2 11 of high temperature furnace controller 18 Digital quantity, and the scale conversion of heated electric current are converted to, the heated current current value of high temperature furnace, the heating in Fig. 4 are transformed to Current limit algorithm, using heated current current value PV and the interior high temperature furnace heated current upper limit set as heated current setting value SV calculates heated current regulated quantity Out2 collectively as the input of heated current limit algorithm algorithm with PI algorithm.Pay attention to Out2 It is only more than heated current upper limit value (SV) Shi Shengxiao at heated current (PV).Once heated current is more than thermocurrent upper limit value, add The magnitude and duration, the heated current that persistently output negative sense changes that thermocurrent limit algorithm is just more than according to electric current adjust defeated Out2 out, which adjusts output Out1 etc. and be superimposed to be formed after synthesis by the output synthesizer with the furnace temperature PID includes The regulated quantity of current limit reduces the input quantity of the phase-shift voltage regulating module, thus by high temperature furnace heated current to reduction Direction adjustment, then maintain heated current be no more than current upper limit value.If what heated current current value was set no more than in adds Thermocurrent upper limit value, then software should skip the PI adjustment process of (closing) the heated current limitation, and keep the increment of Out2 Δ Out2 is zero, therefore heated current limit algorithm is actually that a digitized unidirectional PI adjusts algorithm.

The setting of the heated current limiting element of the high temperature furnace controller, it is ensured that whole service process (including power on Delay startup process) in heated current be no more than the high temperature furnace controller inner setting the heated current upper limit.

To realize that high temperature furnace 5 powers on delay startup, need to control heated current must not forward mutation assay, heated current should be by restriction Rate be slowly increased.The effect of electric current raising speed limiting element can be regarded as: if PID adjusts output valve Out1 and positive dash forward occurs Become, then in actual driving output Out, defined output increment or slope should be become as required.

As previously mentioned, electric current raising speed limiting element calculates the rate of change of heated current simply by heated current sequence, Actually monitor and limit the raising speed of heated current.The high temperature furnace controller limits task by the electric current raising speed in software It executes electric current raising speed limit algorithm (can be PI algorithm), heated current raising speed is limited in and is set in the high temperature furnace controller Within the heated current raising speed upper limit.Once electric current raising speed is more than the interior electric current raising speed upper limit set, electric current raising speed limit algorithm just root The magnitude for being more than according to electric current raising speed and duration, the electric current raising speed for persistently exporting negative sense variation adjust output Out3, i.e. Δ Out3 is negative, and the Out after influencing synthesis is adjusted to reduced direction, reduces the input quantity for driving phase-shift voltage regulating module, from And adjust heated current rate to reduced direction, the final heated current raising speed that influences reduces, and maintains raising speed in heated current Rate, which is no more than in it, sets upper limit value.

The high temperature furnace powers on soft start function, is actually realized by means of electric current raising speed limitation function.In height During warm furnace electrifying startup, by the electric current raising speed limitation function, high temperature furnace heated current is started from scratch with the upper of restriction Raising speed rate slowly increases.Due to heated current limitation function during high temperature furnace electrifying startup simultaneously in action, on It electrically activates process and is usually started from scratch with high temperature furnace electric current and is gradually increasing, until reach the upper current limit set as target, thus It realizes and powers on delay startup.

The function such as the comprehensive adjustment output quantity Out becomes, and there is furnace temperature to adjust, heated current limits and electric current raising speed limits The final regulated quantity of energy.

The cooling protection (afterflow protection) of high temperature furnace: when high temperature furnace completes measurement in high temperature calibrating point (usually 1500 DEG C) Afterwards, it is meant that all measurement work has been completed, according to reason can be to high temperature furnace power-off.But in fact, high temperature furnace is so high At a temperature of stop heating suddenly, internal component such as alundum tube and refractory material can generate contractions because of temperature decrease, easy It is cracked because shrinking everywhere unevenly, influences the technical indicator of high temperature furnace.The purpose of the cooling protection is to allow high temperature furnace It does not power off immediately, but switchs to afterflow and maintain mode, i.e., 5 heated current of high temperature furnace is reduced according to afterflow initial current ratio, and is pressed Freewheel current reduction of speed constantly reduces, and until afterflow is held time then, furnace temperature is down to certain temperature (such as 1200 DEG C or so), passes through Opening/stop control makes major loop contactor power loss, stops heating completely, the cooling of such high temperature furnace at high temperature is more than Temperature fall Add slowly.Above-mentioned protection is also referred to as afterflow protection.The cooling protection function can be separately provided a cooling and be protected by software realization Shield task, it is due to the required precision that controls the time and not bery stringent, therefore can directly with the delay of the cooling protection task when Between i.e. circulation execute foundation of the period as time cumulation.When starting cooling protection, the afterflow button on console need to be only pressed Or afterflow order is sent to high temperature furnace controller.The afterflow button is connected to an On-off signal port of single-chip microcontroller.

Main current supply circuit electric terminal temperature rise inspection, overtemperature alarm and protection:

About high current electric terminal: in high temperature furnace operational process, especially temperature-rise period, heated current is big, main power supply Electric terminal (including each terminals, insurance, contactor etc.) through a long time operation in circuit may go out because of reasons such as oxidations Existing poor contact, causes to generate heat, if cannot discover and rule out in time, will lead to vicious circle, until thoroughly burning out, influences equipment Normal operation, or even cause safety accident.

There are many main current supply circuit electric terminal temperature rise inspection hardware plan, relatively flexibly, depend primarily on thermometric surface The Choice of thermometer.Integrated temperature sensor DS18B20 can be used and be fabricated to simple land surface pyrometer, i.e., by required number The DS18B20 of amount is separately fixed in the buckle of sheet metal production, and is adjacent to respectively, is fixedly mounted on the monitored electricity easily to generate heat Gas contact position, is formed the land surface pyrometer 19, and the quantity of land surface pyrometer can be arranged (wherein one according to actual needs Branch is for measuring environment temperature), the temperature rise inspecting interface 17 of high temperature furnace controller is connected to by lead respectively, passes through the temperature Inspecting interface 17 is risen by 1 I/O line of the corresponding single-chip microcontroller of each land surface pyrometer (DS18B20).Except for measuring environment temperature Outside the thermometer of degree, other land surface pyrometers are separately mounted on 3 grades of transformer and export to 6 input terminal of high temperature stove heating body Monitored electric terminal position in low-voltage and high-current circuit, Yi Fare.

By temperature rise inspection in software and overtemperature prote task, tour inspection carried out to the temperature rise at each monitoring position, one Denier finds to have more than the electric terminal of normal temperature rise, will be issued and be alarmed by console, communication port and acoustic and light information, if electrically connecing Point overtemperature reaches protection temperature, and the high temperature furnace controller 18 is by opening, and/stopping the control of control interface 14 to open/it is fast to stop latching circuit 1 Speed cuts off main current supply circuit, implements electric terminal overtemperature prote, avoids the further expansion of failure.Temperature rise inspection and overtemperature prote The priority of task is chosen as minimum, and the time of one temperature spot of inspection has no strict demand, is several seconds even tens of seconds.

The above is only the preferred embodiment of the utility model, it is noted that for the ordinary skill of technical field For personnel, without departing from the principle of this utility model, several improvement can also be made, wound is not being paid in these improvement It also should be regarded as the protection scope of the utility model under the premise of the property made labour.

Claims (4)

1. a kind of high temperature furnace control device, characterized in that it includes opening/stopping latching circuit (1), phase-shift voltage regulating module (2), transformation Device (3), current transducer (4), temperature-control heat couple (7), high temperature furnace controller (18), console (20), open/stop latching circuit (1), phase-shift voltage regulating module (2), transformer (3), current transducer (4) are successively set on the heating power supply inlet wire of high temperature furnace；

The high temperature furnace controller includes furnace temperature signal conditioning circuit (9), A/D1(10), A/D2(11), D/A(12), D/A output Driver (13) opens/stops control interface (14), CPU(15), communication interface (16), the working end of the temperature-control heat couple (7) is set In in effective operation temperature area of high temperature furnace (5), the reference end of temperature-control heat couple (7) is connected to furnace temperature signal condition through extension wire The output end of the input terminal of circuit (9), furnace temperature signal conditioning circuit (9) is connected to the A/D1(10) input terminal, the electricity The input terminal of flow transmitter (4) is connected to the heating power supply inlet wire of high temperature furnace (5), and the output end of the current transducer (4) connects It is connected to the input terminal of (11) the A/D2, the output end of the D/A (12) is connected to the defeated of the D/A output driver (13) Enter end, the output end of the D/A output driver (13) is connected to the input terminal of the phase-shift voltage regulating module (2), the phase shift The output end of voltage regulating module (2) is connected to the primary circuit of the transformer (3), the output for opening/stopping control interface (14) End is connected to the input terminal for opening/stopping latching circuit (1)；

The A/D1(10) output end, A/D2(11) output end, D/A(12) input terminal, open/stop control interface (14) Output end, communication interface (16) output end be all connected to CPU (15), the communication interface (16) pass through RS-232 mouthfuls connection To console (20).

2. high temperature furnace control device according to claim 1, characterized in that high temperature furnace controller (18) further includes that temperature rise is patrolled It examines interface (17), the input terminal of temperature rise inspecting interface (17) connects more land surface pyrometers (19), the temperature rise inspecting interface (17) output end and CPU(15) connection, the temperature-sensing probe of the land surface pyrometer (19), which is separately mounted on, is easy fever Low-voltage, high-current electric terminal position.

3. high temperature furnace control device according to claim 1, characterized in that the input terminal of current transducer (4) is connected to The heating power supply inlet wire of high temperature furnace (5), the high temperature furnace controller (18) receive current transducer (4) by A/D2 (11) Output signal.

4. high temperature furnace control device according to claim 2, characterized in that in the thermometer of temperature rise inspecting interface connection, There is a land surface pyrometer for measuring environment temperature, it is supreme that other land surface pyrometers are separately mounted on transformer secondary output output Monitored electric terminal position in the low-voltage and high-current circuit of warm stove heating body input terminal, Yi Fare.