CN107953018B - Recognition circuit for realizing rapid switching of main arc and transferred arc of plasma cutting machine - Google Patents
Recognition circuit for realizing rapid switching of main arc and transferred arc of plasma cutting machine Download PDFInfo
- Publication number
- CN107953018B CN107953018B CN201711244557.XA CN201711244557A CN107953018B CN 107953018 B CN107953018 B CN 107953018B CN 201711244557 A CN201711244557 A CN 201711244557A CN 107953018 B CN107953018 B CN 107953018B
- Authority
- CN
- China
- Prior art keywords
- arc
- circuit
- hall sensor
- current detection
- detection hall
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K10/00—Welding or cutting by means of a plasma
- B23K10/006—Control circuits therefor
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Mechanical Engineering (AREA)
- Power Engineering (AREA)
- Arc Welding Control (AREA)
Abstract
The invention relates to the technical field of plasma cutting machines, in particular to an identification circuit for realizing quick switching of a main arc and a transferred arc of a plasma cutting machine, so that the cutting machine can easily realize a grid cutting function. Direct current bus connection is at inverter circuit's input, and inverter circuit's output is connected the primary side of transformer, and secondary rectifier circuit, its characterized in that are being connected to the secondary of transformer: the plasma cutting machine is characterized by further comprising a hysteresis type transient arc breaking identification circuit, a transfer arc current and ground wire current detection Hall sensor, wherein the transfer arc current detection Hall sensor is connected in front of a positive electrode branching node of the output end of the secondary rectification circuit, the ground wire current detection Hall sensor is connected between the positive electrode branching node and a cutting parent metal, the output ends of the transfer arc current and ground wire current detection Hall sensor are connected to two input ends of the hysteresis type transient arc breaking identification circuit, and signals are output to a control system of the plasma cutting machine after being compared by the hysteresis type transient arc breaking identification circuit.
Description
Technical Field
The invention relates to the technical field of plasma cutting machines, in particular to an identification circuit for realizing rapid switching of a main arc and a transferred arc of a plasma cutting machine.
Background
At present, many welding power supply manufacturers in China produce contact type plasma cutting machines, but most manufacturers still cannot well realize the grid cutting function. The main difficulty is that in the process of cutting the parent metal, the main arc leaves the process of cutting the parent metal (similar to instantaneous arc interruption), the speed of the cutting current dropping to 0A is too high, and a control system cannot timely capture the initial moment of the process or can only occasionally capture the final stage of the process, so that the control system cannot timely respond to the initial moment, and direct arc interruption is caused. At present, a circuit is needed to be designed, and the arc breaking process can be quickly captured, so that arc blowout is avoided, and grid cutting is completed.
Disclosure of Invention
The invention aims to overcome the defects in the background art and provide an identification circuit for realizing the rapid switching of a main arc and a transferred arc of a plasma cutting machine, so that the cutting machine can well capture the starting time of the main arc leaving the parent metal cutting process in the cutting process, and the grid cutting function can be easily realized under the condition that a control system has good dynamic response capability.
The technical scheme adopted by the invention is as follows:
realize plasma cutting machine owner electric arc and transfer recognition circuit of arc fast switch over, including direct current bus, inverter circuit, a transformer, vice limit rectifier circuit and transfer arc control circuit, direct current bus connects the input at inverter circuit, inverter circuit's output is connected the former limit of transformer, vice limit rectifier circuit is being connected to the vice limit of transformer, the negative pole of vice limit rectifier circuit output connects the burning torch electrode, the positive pole divides two tunnel, be connected with the cutting parent metal all the way, another way is through the nozzle that shifts arc control circuit connection burning torch, its characterized in that: the plasma cutting machine further comprises a hysteresis type transient arc breaking identification circuit, a transfer arc current detection Hall sensor and a ground wire current detection Hall sensor, wherein the transfer arc current detection Hall sensor is connected in front of a positive bifurcation node of the output end of the secondary side rectification circuit, the ground wire current detection Hall sensor is connected between the positive bifurcation node and a cutting parent metal, the output ends of the transfer arc current detection Hall sensor and the ground wire current detection Hall sensor are connected to two input ends of the hysteresis type transient arc breaking identification circuit, and after comparison of the hysteresis type transient arc breaking identification circuit, signals are output to a control system of the plasma cutting machine.
The hysteresis type transient arc-breaking recognition circuit comprises a comparator, wherein one input pin of the comparator is grounded through a capacitor C124, connected with the output end of the transferred arc current detection Hall sensor through a resistor R210, and connected with the output end of the ground current detection Hall sensor through a resistor R209; the other input pin of the comparator is grounded through a capacitor C132, and is also connected with the output end of the ground current detection Hall sensor through a resistor R207, and the output end of the comparator is connected with a control system of the plasma cutting machine.
The invention has the following beneficial effects: the cutting machine can well capture the initial time of the main arc leaving the parent metal cutting process in the cutting process, and the grid cutting function is easily realized under the condition that a control system has good dynamic response capability; the principle is simple, and the cost is low; the sensitivity is high, the response speed is very high, and the hardware compatibility is strong.
Drawings
Fig. 1 is a schematic diagram of the circuit structure of the present invention.
Fig. 2 is an enlarged schematic diagram of the transferred arc control circuit of fig. 1.
Fig. 3 is an enlarged schematic diagram of the hysteresis type transient arc breakage recognition circuit in fig. 1.
Fig. 4 is a schematic diagram of a circuit connection structure of the transferred arc current detection hall sensor CT1 and the ground current detection hall sensor CT 2.
Detailed Description
The present invention is further illustrated but is not limited by the following examples.
As shown in fig. 1 to 4, the identification circuit for realizing the rapid switching between the main arc and the transferred arc of the plasma cutting machine comprises a direct current bus 2, an inverter circuit 3, a transformer T1, a secondary rectification circuit 4 and a transferred arc control circuit 5, wherein the direct current bus is connected with the input end of the inverter circuit, the output end of the inverter circuit is connected with the primary side of the transformer, the secondary rectification circuit is connected with the secondary side of the transformer, the negative electrode of the output end of the secondary rectification circuit is connected with the electrode of the cutting gun through a reactor, the positive electrode is divided into two paths, one path is connected with the cutting parent metal, and the other path is connected with the nozzle of the cutting gun through the transferred arc control circuit. The plasma cutting machine also comprises a hysteresis type transient arc-breaking identification circuit 1, a transfer arc current detection Hall sensor CT1 and a ground wire current detection Hall sensor CT2, wherein the transfer arc current detection Hall sensor is connected in front of a positive electrode branching node at the output end of a secondary side rectification circuit, the ground wire current detection Hall sensor is connected between the positive electrode branching node and a cutting mother material, the output ends of the transfer arc current detection Hall sensor and the ground wire current detection Hall sensor are connected to two input ends of the hysteresis type transient arc-breaking identification circuit, and after comparison of the hysteresis type transient arc-breaking identification circuit, signals are output to a control system of the plasma cutting machine.
As shown in fig. 3, the hysteresis-type transient arc-breaking recognition circuit includes a comparator U16B, one of the input pins (pin 6) of the comparator is grounded through a capacitor C124, connected to the output terminal of the transferred arc current detection hall sensor through a resistor R210, and further connected to the output terminal of the ground current detection hall sensor through a resistor R209; the other input pin (pin 5) of the comparator is grounded through a capacitor C132, and is also connected with the output end of the ground current detection Hall sensor through a resistor R207, and the output end (pin 7) of the comparator is connected with a control system of the plasma cutting machine.
Description of the circuit principle:
1. the working principle of the main loop of the contact type plasma cutting power supply is explained as follows:
and the alternating current power supply is subjected to full-wave rectification through the rectifier bridge and then is connected to the side 2 of the direct current bus to complete the filtering and energy storage functions. The inverter circuit 3 converts the direct current on the direct current bus 2 into an alternating current square wave in a full-bridge inversion mode, and then the alternating current square wave generated by the inverter circuit 3 is subjected to boosting (or voltage reduction) processing through the main transformer and then is converted into direct current for output through the secondary rectification circuit 4.
When the cutting is not carried out, the nozzle and the electrode of the cutting gun are in a closed state.
At the moment of pressing the torch, the control system firstly opens the gas valve, the inverter circuit 3 and the transferred arc control circuit 5 to enable the torch to work, and because the nozzle and the electrode of the cutting torch are still in a closed state, the output current of the cutting machine finishes the operation through the Hall sensor CT1 (transferred arc current detection), the transferred arc control circuit 5, the nozzle of the cutting torch, the electrode of the cutting torch and the reactor, and the output is in a temporary short circuit state. After the air valve is opened, the cutting gun nozzle and the cutting gun electrode are flicked along with the rise of air pressure, the output of the cutting machine is converted from a short circuit state to an arc discharge state, arc light is sprayed out from the nozzle along with air flow, and the current output by the cutting machine in the process is called transferred arc current.
When the transferred arc current contacts the cutting parent metal, the cutting machine starts a formal cutting process, at the moment, the control system closes the transferred arc control circuit 5, the output current of the cutting machine passes through the Hall sensor CT1 (transferred arc current detection), the Hall sensor CT2 (ground wire current detection), the cutting parent metal, the cutting gun nozzle, the cutting gun electrode and the reactor to complete operation, and the output current of the cutting machine in the process is called as main arc current. Therefore, in the whole cutting process, when the transferred arc is ignited, current passes through the Hall sensor CT1 (transferred arc current detection), and no current passes through the Hall sensor CT2 (ground wire current detection); during normal cutting, the Hall sensor CT1 (transferred arc current detection) and the Hall sensor CT2 (ground wire current detection) are both provided with currents which pass through and are equal in magnitude.
In the cutting process, the control system controls the inverter circuit 3 at a higher response speed according to the sampled signal so as to realize closed-loop regulation in the cutting process.
In the non-grid cutting mode, when the main electric arc leaves the cutting base metal in the normal cutting process, the output of the cutting machine can be directly closed after the arc is broken. In the grid cutting mode, when the main arc leaves the cutting base metal in the normal cutting process, the cutting machine must timely open the transferred arc control circuit 5 and fully adjust the inverter circuit 3 at the initial stage when the current of the main arc begins to decrease, so that the cutting machine can reestablish the transferred arc and maintain the arc spraying of the cutting gun.
2. The operation principle of the hysteresis type transient arc-breaking identification circuit 1 is explained as follows:
the hysteresis type transient arc-breaking identification circuit 1 is based on the working principle of a hysteresis comparator, wherein If1 is transferred arc current, and If2 is ground current.
In the whole cutting process, in the transferred arc striking stage, if1 has voltage, the capacitor C124 is charged through the resistor R210, if2 has no voltage, the capacitor C132 keeps a 0-pin voltage state, the voltage of the pin 6 of the U16 is higher than the voltage of the pin 5, and the pin 7 of the comparator U16 is in a low-level output state.
After the transferred arc current contacts the cutting base material and normal cutting is started, if1 is slowly reduced to 0 along with the closing of the transferred arc, if2 is gradually increased to a preset current value, in the process of reducing If1, the capacitor C124 is rapidly charged from If2 through the resistor R209, meanwhile, the capacitor C132 is also charged from If2 through the resistor R207, but the charging speed is lower than that of the capacitor C124, so that the maximum voltage is reached in pin 6 of U16 before pin 5, and pin 7 of the comparator U16 keeps a low-level output state.
At the moment that the main arc leaves the cutting parent metal in the cutting process, the output current If2 of the cutting machine is reduced at a very fast speed, and when If2 begins to reduce, because the charging and discharging speeds of the capacitor C124 are much higher than those of the capacitor C132, the voltage of the pin 6 of the comparator U16 is lower than the voltage of the pin 5 at the initial stage when the current begins to reduce steeply, so that the pin 7 of the U16 outputs a high level. The control system immediately turns on the transferred arc control circuit 5 and fully adjusts the inverter circuit 3 after receiving the high level signal, so that the cutting machine reestablishes the transferred arc at the initial stage of the instant drop of the main arc current and maintains the arc spraying of the cutting gun. After the transferred arc striking is successful, if1 has voltage, the capacitor C124 is charged through the resistor R210, if2 is rapidly reduced to 0, the capacitor C132 is also reduced to a 0-voltage state, the voltage of pin 6 of U16 is higher than the voltage of pin 5, and pin 7 of the comparator U16 is in a low-level output state.
From the above, the hysteresis type transient arc-breaking recognition circuit 1 outputs a high level only at the moment when the main arc leaves the cutting base material in the cutting process, and the other processes are kept in a low level state.
The foregoing lists merely illustrate specific embodiments of the invention. It is obvious that the invention is not limited to the above embodiments, but that many variations are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the present invention are to be considered within the scope of the invention.
Claims (1)
1. Realize plasma cutting machine owner electric arc and transfer recognition circuit of arc fast switch over, including direct current generating line (2), inverter circuit (3), transformer (T1), vice limit rectifier circuit (4) and transfer arc control circuit (5), direct current generating line connects the input at inverter circuit, the primary side of transformer is connected to inverter circuit's output, vice limit rectifier circuit is being connected to the vice limit of transformer, the negative pole of vice limit rectifier circuit output connects the burning torch electrode, the positive pole divides two the tunnel, be connected with the cutting parent metal all the way, another way is through the nozzle that shifts the arc control circuit connection burning torch, its characterized in that: the plasma cutting machine is characterized by further comprising a hysteresis type transient arc breaking identification circuit (1), a transfer arc current detection Hall sensor (CT 1) and a ground wire current detection Hall sensor (CT 2), wherein the transfer arc current detection Hall sensor is connected in front of a positive electrode branching node at the output end of the secondary side rectifying circuit, the ground wire current detection Hall sensor is connected between the positive electrode branching node and a cutting parent metal, the output ends of the transfer arc current detection Hall sensor and the ground wire current detection Hall sensor are connected to two input ends of the hysteresis type transient arc breaking identification circuit, and after comparison of the hysteresis type transient arc breaking identification circuit, signals are output to a control system of the plasma cutting machine;
the hysteresis type transient arc-breaking identification circuit comprises a comparator (U16B), wherein one input pin of the comparator is grounded through a capacitor C124, is connected with the output end of a transferred arc current detection Hall sensor through a resistor R210, and is also connected with the output end of a ground current detection Hall sensor through a resistor R209; the other input pin of the comparator is grounded through a capacitor C132, and is also connected with the output end of the ground current detection Hall sensor through a resistor R207, and the output end of the comparator is connected with a control system of the plasma cutting machine.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711244557.XA CN107953018B (en) | 2017-11-30 | 2017-11-30 | Recognition circuit for realizing rapid switching of main arc and transferred arc of plasma cutting machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711244557.XA CN107953018B (en) | 2017-11-30 | 2017-11-30 | Recognition circuit for realizing rapid switching of main arc and transferred arc of plasma cutting machine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107953018A CN107953018A (en) | 2018-04-24 |
| CN107953018B true CN107953018B (en) | 2023-04-14 |
Family
ID=61962011
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711244557.XA Active CN107953018B (en) | 2017-11-30 | 2017-11-30 | Recognition circuit for realizing rapid switching of main arc and transferred arc of plasma cutting machine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107953018B (en) |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN200991804Y (en) * | 2006-12-19 | 2007-12-19 | 江苏科技大学 | Super portable interference-free arc-striking air plasma cutting machine |
| US20140069895A1 (en) * | 2012-04-04 | 2014-03-13 | Hypertherm, Inc. | Automated cartridge detection for a plasma arc cutting system |
| EP3126086A1 (en) * | 2014-03-31 | 2017-02-08 | Hypertherm, Inc. | Wide bandgap semiconductor based power supply for plasma cutting systems and related manufacturing method |
| EP3443821B1 (en) * | 2016-04-12 | 2023-05-03 | Hypertherm, Inc. | Systems and methods for providing power for plasma arc cutting |
| CN205869684U (en) * | 2016-07-18 | 2017-01-11 | 上海沪工焊接集团股份有限公司 | Plasma cutting machine guide arc control circuit |
| CN207521860U (en) * | 2017-11-30 | 2018-06-22 | 杭州凯尔达电焊机有限公司 | Realize the identification circuit that plasma cutting machine main arc is switched fast with transferred arc |
-
2017
- 2017-11-30 CN CN201711244557.XA patent/CN107953018B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN107953018A (en) | 2018-04-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108696164B (en) | Flyback single-phase photovoltaic grid-connected micro inverter controlled by DCM frequency conversion and control method | |
| CN103997198B (en) | The short time voltage of converter is interrupted immunity to interference and is promoted circuit and converter | |
| CN105526833A (en) | Quick charging method for energy-storage capacitors of electronic detonators | |
| CN102350581B (en) | Medium-voltage capacitive energy storage welding machine | |
| CN207521860U (en) | Realize the identification circuit that plasma cutting machine main arc is switched fast with transferred arc | |
| CN110152887B (en) | Constant-current intermediate-frequency dust removal power supply spark flashover detection processing system based on FPGA | |
| CN107953018B (en) | Recognition circuit for realizing rapid switching of main arc and transferred arc of plasma cutting machine | |
| CN111555710A (en) | PLC (programmable logic controller) driving circuit of photovoltaic shutoff device and control method thereof | |
| CN203052718U (en) | High-voltage electronic ignition device of calorimeter | |
| CN201862898U (en) | Energy-saving safety controller of electric welding machine | |
| CN208908371U (en) | A kind of pre-charge system of electric car | |
| CN205847076U (en) | AC D/C power | |
| CN104600970B (en) | Switch power supply circuit and protection circuit and method for avoiding false triggering of over-current protection | |
| JP3458632B2 (en) | Welding voltage detection method and arc welding machine | |
| CN215468702U (en) | Arc striking circuit of stud welding machine | |
| CN101844277B (en) | Discharging circuit for welding discharger | |
| CN113819494A (en) | Low-power-consumption flame ion detection circuit and method with adjustable sensitivity | |
| CN202663172U (en) | Novel lithium battery charger | |
| CN206316513U (en) | A kind of electric welding machine safety control | |
| CN113319400A (en) | Arc striking circuit of stud welding machine | |
| CN203446088U (en) | Electronic ballast capable of delay starting in hot lamp state | |
| CN207806844U (en) | A kind of non-contact arc ignition circuit and argon arc welding machine | |
| CN110880399B (en) | Pipeline demagnetizer | |
| CN201833101U (en) | Welding power supply circuit with input current limiting function | |
| CN111889855A (en) | Cutter drive circuit, cutter control device and plasma cutting machine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |