CN2399898Y - Frequency variable operation induction heating equipment - Google Patents
Frequency variable operation induction heating equipment Download PDFInfo
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- CN2399898Y CN2399898Y CN 99250636 CN99250636U CN2399898Y CN 2399898 Y CN2399898 Y CN 2399898Y CN 99250636 CN99250636 CN 99250636 CN 99250636 U CN99250636 U CN 99250636U CN 2399898 Y CN2399898 Y CN 2399898Y
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- 230000006698 induction Effects 0.000 title claims abstract description 20
- 238000010438 heat treatment Methods 0.000 title abstract description 10
- 239000003990 capacitor Substances 0.000 claims abstract description 14
- 238000010304 firing Methods 0.000 claims description 6
- 230000001939 inductive effect Effects 0.000 claims description 6
- 230000008859 change Effects 0.000 claims description 4
- 230000001681 protective effect Effects 0.000 claims description 3
- 230000015572 biosynthetic process Effects 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 7
- 238000003723 Smelting Methods 0.000 abstract description 6
- 230000008569 process Effects 0.000 abstract description 6
- 238000012545 processing Methods 0.000 abstract description 3
- 230000000052 comparative effect Effects 0.000 abstract 1
- 238000002844 melting Methods 0.000 description 11
- 230000008018 melting Effects 0.000 description 11
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 238000001914 filtration Methods 0.000 description 5
- 238000007499 fusion processing Methods 0.000 description 5
- 238000002955 isolation Methods 0.000 description 5
- 230000006870 function Effects 0.000 description 4
- 230000002159 abnormal effect Effects 0.000 description 3
- 230000005611 electricity Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 230000008901 benefit Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 230000005520 electrodynamics Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000008447 perception Effects 0.000 description 1
- 230000005622 photoelectricity Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
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Abstract
The utility model relates to induction heating equipment capable of frequency variable operation. A power supply unit is formed by the sequential connection of a rectification circuit, a filter circuit, an inverter circuit and a load. The utility model is characterized in that the inverter circuit is an inverter bridge circuit which is composed of four insulated-gate bipolar transistors (IGBT) V1, V2, V3, V4, and the output of the bridge circuit is added to a parallel resonance circuit which is composed of an induction load L and a compensation capacitor C through a medium frequency transformer B; a control circuit for an inverter adopts a 89C51 single chip computer as a core, and adopts a mediate frequency voltage signal as an input signal; the input signal is used for comparative tracking with the phase of output trigger pulses, and the output trigger pulses can control the V1/V4 and the V2/V3 to be conducted alternately. The utility model can realize frequency variable operation in the process of smelting, and the requirement for the smelting of different frequency points, and can maximally satisfy the technological requirements of modern metallothermic processing.
Description
The utility model relates to the melting technique of metal material, and a kind of variable frequency induction heater is provided especially.
Induction heating equipment is widely used in operations such as the melting of metal material and goods, diathermanous, heat treatment and welding, and it is fast to have firing rate, and oxide layer is thin, iron loss is few, furnace temperature advantage such as control easily.What traditional induction heating equipment adopted is thyristor intermediate frequency power supply, thyristor is a commutation cutoff type device, after the pipe conducting, can only rely on outside converter circuit to make the electric current that flows through pipe drop to zero, or make the voltage reversal at pipe two ends and turn-off, thereby when thyristor is used for induction heating equipment, except that need are provided with start-up circuit and forced commutation circuit, also because the turn-off time of thyristor is long, and switching loss is big, switching frequency hangs down problems such as reaching the easy failure of starting.Its corresponding inverter control circuit generally adopts separating component or common integrated circuit to form, can only in fixing frequency range, carry out the tracking of load resonant frequency, and complex circuit, failure rate height, maintenance difficult.Intrinsic limitation (reverse blocking shutoff type device just because of conventional art, starting difficulty, be difficult for being applied in the frequent starting occasion), thereby equipment can not satisfy the requirement of modern metal heat treatmet technology, as improving the material degree that homogenizes, then in fusion process, require the firing equipment variable frequency, i.e. high frequency melting, low frequency stirs; The research material novel process for smelting requires equipment can be operated in different frequency range etc., and these require traditional heating equipment to be difficult to satisfy.
The purpose of this utility model is to provide a kind of variable frequency induction heater, it can overcome above skill water defective, realize the variable frequency in the fusion process, and requirement such as different frequent points melting, can satisfy the requirement of modern metal heat treatmet technology to greatest extent.
The utility model provides a kind of variable frequency induction heater, form by power supply and body of heater two large divisions, power unit is wherein connect in proper order by rectification circuit, filter circuit, inverter circuit, load and forms, load is joined by inverter control circuit and inverter circuit, join by rectifier control circuit and rectification circuit simultaneously, it is characterized in that:
Described inverter circuit is by V
1, V
2, V
3, V
4Four inversion bridge circuits that IGBT forms, V
1/ V
4And V
2/ V
3Control alternate conduction respectively by inverter control circuit, bridge circuit output is added on the antiresonant circuit of inductive load L and building-out capacitor C composition by intermediate frequency transformer B;
The core of described inverter control circuit is the 89C51 single-chip microcomputer, and its voltage of intermediate frequency signal with detected inverter circuit output is an input signal, compares tracking with the trigger impulse phase place of exporting, and the trigger impulse of its output is by IGBT drive circuit control V
1/ V
4And V
2/ V
3Alternate conduction.
In addition, the utility model also adopts integrated dephasing thyristor module ZLMK to constitute rectified three-phase circuit; Rectifier control circuit is made up of control and protection two parts; Threephase current transformer IM
1, IM
2, IM
3Output by with P
6The signal of current limit value relatively amplifies, through diode D
17Again with power given potentiometer P
7Output is at U
30DCarry out the synthetic formation of signal control circuit part among the TL084, its output connects the control end of rectification module ZLMK to regulate the rectification module output voltage; The output of voltage of intermediate frequency instrument transformer B and power given potentiometer P
7Output by XOR gate A
1Control triode T
3Base stage constitute protective circuit part, T
3Collector electrode and the control end of rectification module link.
The B of isolating transformer described in the utility model is many tapped transformers.Described capacitor C can be switched by the contact of intermediate frequency contactor and change its capacity.Described V
1, V
2, V
3, V
4Two ends parallel resistance R respectively
SC
SConstitute the RC resistance capaciting absorpting circuit.
Specifically, the correlation of each part of the utility model is seen accompanying drawing 1, Fig. 2.
Three-phase alternating current becomes Rectified alternating current through integrated dephasing thyristor module ZLMK, becomes the smooth direct current electricity after smoothing reactor Ld filtering, as the constant-current source of inverter; The inverter bridge of being made up of IGBT (V1, V2, V3, V4) is converted into the intermediate frequency alternate electric energy with direct current energy, and send into by many taps intermediate frequency isolating transformer B in the shunt load of LC (L is that inductor coil, C are compensation condenser) composition, this mode can make same smelting equipment adapt to the requirement of different loads impedance as long as change the tap of transformer, mates to reach optimum load.Control system comprises rectifier control circuit (see figure 3) and inverter control circuit (see figure 5); Rectifier control circuit is realized the power adjustments of power supply, dam pressure and over-current over-voltage protection function.Inversion control is finished frequency-tracking, pulse-triggered and isolation drive function, because being used for the load of melting has nothing in common with each other, load parameter changes greatly in the fusion process, thereby inverter control circuit tackles load resonant frequency and follow the tracks of, and makes to load on to be in the quasi-resonance state in the fusion process all the time.
The utility model adopts brand-new technology of frequency tracking, all can finish automatically from it any load and swash the overall process that starts to the self-excitation operation, and load is in the quasi-resonance state all the time.Its principle is to be current mode (constant-current source) inverter according to shunt chopper, the grid trigger impulse of IGBT must with the electric current of intermediate frequency same-phase of inverter output, thereby by detecting the voltage of intermediate frequency signal, adopt regularly principle, voltage of intermediate frequency is lagged behind the electric current of intermediate frequency set time all the time, system is operated near resonance condition (capacitive partially), can realize frequency-tracking.Promptly at first send suitable fixed frequency pulse drive signal after the start by MCU, system is started by separate excitation, set up the voltage of intermediate frequency signal, increase along with power, after intermediate frequency voltage reaches set point, MCU just can detect the voltage of intermediate frequency signal, and compare with the phase place of trigger impulse, when lag time oversize (surpass setting-up time scope) the inclined to one side capacitive of illustrative system too big, should reduce the frequency of trigger impulse, and too short when lag time, illustrative system is perception partially, thereby should increase the frequency of trigger impulse, MCU is by constantly detecting, judge and correction, just can follow the tracks of the variation of load resonant frequency all the time.
The utlity model has following characteristics:
1. adopt integrated dephasing thyristor module to constitute rectified three-phase circuit.
2. adopt self-turn-off device IGBT (igbt) to form the inversion bridge circuit.
3. be that core constitutes inverter control circuit with MCU, finish automatically from it and swash the overall process that starts to the self-excitation operation.
4. the correspondent frequency following function can automatically be operated in different frequency ranges, can automatically follow the tracks of the variation of load resonant frequency again at different frequency range.
5. be that core constitutes inverter and inductive load working state monitoring and protection system with the NOR gate circuit.
6. adopt many taps isolating transformer output intermediate frequency power, can the regulating load impedance, adapts to different inductive loads, mate Maximum Power Output to reach optimum load.
7. adopt automatic switchover compensation condenser mode to change resonance frequency, realize the variable frequency in the fusion process.
8. adopt the mode of parallel resonance to form the load resonant tank circuit.
9. the overall process of smelting operation is finished in MCU control able to programme automatically, is applicable to automatic continuous production.
In a word, the utility model is owing to adopt above technological means, novel induction melting equipment can pass through compensation capacitors, the tap that changes isolating transformer is adapted to different inductive loads, reach the purpose of a tractor serves several purposes, be that metal can melting under different induction frequencies,, can find best smelting process condition by contrast test; And, can use different frequencies to carry out induction melting by compensation capacitors to same load, reach the high frequency melting, the purpose that low frequency stirs, promptly by the high frequency melting, can Fast Heating, to alleviate oxidation, to reduce scaling loss, stir by low frequency, improve the degree that homogenizes of material.Under any circumstance, inverter control circuit can both be followed the tracks of the variation of load resonant frequency, makes to load on to be in the quasi-resonance state in the heating process all the time.
Below by embodiment in detail the utility model is described in detail.
Accompanying drawing 1 is the utility model main circuit block diagram.
Accompanying drawing 2 is the utility model inversion schematic diagram.
Accompanying drawing 3 is the utility model rectifier control circuit.
Accompanying drawing 4 is the utility model rectification control principle figure.
Accompanying drawing 5 is the utility model inverter control circuit.
Accompanying drawing 6 is the utility model inverter control circuit.
Accompanying drawing 7 is the utility model inverter control circuit.
Accompanying drawing 8 is the utility model IGBT drive circuit.
Accompanying drawing 9 is the utility model inverter control circuit.
Accompanying drawing 10 shows for the utility model working state signal.
Embodiment
Select the 75A of SIEMENS company for use, 1700V IGBT module constitutes inverter, and isolated drive circuit selects for use the M57962L of MITSUBISHI company to succeed in developing 5KG induction melting equipment.
Output dc voltage is 500V during fusing, and direct current is 54A, and power output is 27KW, and the resonance frequency of load is 5681HZ during the high frequency fusing, and fusing time is 9min; The resonance frequency of load was 2143Hz when low frequency stirred, and owing to electrodynamic squeezing action, melt sharply seethed up and down in the crucible when low frequency stirred, and tangible hump appears in melt liquid level.
Fig. 1 is the main circuit block diagram
The three-phase main-frequency AC energy becomes Rectified alternating current after the rectification circuit rectification, become level and smooth direct current after filter circuit filtering, sends into inverter; By inverter control circuit control, inverter becomes the midfrequent AC electric energy with dc inverter, is added in the load, realizes the purpose of induction heating.
Fig. 2 is the inversion schematic diagram
The ABC three-phase electricity is after rectification module ZLMK rectification, through filter inductance L
dBecome constant DC stream source after the filtering.Four IGBT (V
1, V
2, V
3, V
4) form four brachium pontis of inversion, control V respectively by inverter control circuit
1/ V
4And V
2/ V
3Alternate conduction just becomes direct current into medium frequency alternating current, and is added to by intermediate frequency transformer B on the antiresonant circuit of inductance L (inductive load), capacitor C composition.The capacity of building-out capacitor C can switch by the contact of intermediate frequency contactor, to realize variable frequency.V
1, V
2, V
3, V
4Two ends parallel resistor R
S, capacitor C
SBe used to constitute the RC resistance capaciting absorpting circuit, the surge voltage that causes owing to the stray inductance on the circuit when turn-offing to absorb IGBT.SCR and R form discharge loop, start when abnormal conditions (stopping as inversion) take place, so that release filter inductance L
dThe middle electric energy that stores prevents that inversion device IGBT from damaging because of overvoltage.
Fig. 3 is the rectifier control circuit block diagram
Regulate the power given potentiometer and can regulate the output dc voltage of rectification module, thereby regulate the power output of inverter.When the current transformer output signal is lower than current limit value, diode D
17End, constitute open-loop control system, power output is linear to be increased.When the current transformer output signal is higher than current limit value, diode D
17Conducting constitutes closed-loop control system, the increase of restriction output current.
XOR gate A among the figure
1Function be to prevent inversion device failure or output inductor short circuit and the protective circuit that is provided with.When set value of the power surpasses given threshold voltage (comparator A exports high level), and the voltage of intermediate frequency instrument transformer does not surpass when starting voltage of intermediate frequency set point (comparator B output low level) as yet, the output high level is after holding circuit after NOR gate circuit is judged, turn-off the rectification module control signal by triode, making its output voltage is zero; Diode D is set
7, be the erroneous judgement that causes for the fluctuation that prevents because of voltage of intermediate frequency instrument transformer output signal, diode D when comparator B output low level
7Conducting is forced the output of comparator A to draw to be low level (its input signal is inoperative), and when comparator B output high level, diode D
7End, at this moment, comparator A has only the output high level, and promptly voltage of intermediate frequency should surpass set point, could normally start (XOR gate output low level, triode T
3By), and when comparator A is output as low level (abnormal conditions such as inversion device failure or the short circuit of output inductor), XOR gate output high level, triode T
3Conducting, thus turn-off control signal.
Fig. 4 is rectification control principle figure
The threephase current transformer output signal is through diode D
10-D
13Rectification, capacitor C
22, resistance R
45Become level and smooth direct current signal after the filtering.By P
3Sampling is again through R
51, R
52, R
53, C
24, C
25The RC filter circuit that constitutes is delivered to the TL084A-3 pin, and TL084A is connected into voltage follower and plays buffer action, and its 1 pin output connects TL084B end of oppisite phase 6 pin, and its in-phase end 5 pin connect electric current and limit potentiometer P
6, after the TL084B comparison operation, by 7 pin output signals and through diode D
17Deliver to 12 pin of TL084D.And power adjustments potentiometer P
7Voltage signal after the TL084C isolation drive, by 8 pin output voltage signals through R
59, R
60Deliver to 12 pin of TL084D after the dividing potential drop simultaneously, after add operation, pass through R
63The output control signal is added to rectification module 2 pin control ends, regulates rectifier output voltage.
Diode D
18, potentiometer P
5Be used to limit control signal voltage magnitude or rectification module output voltage.
Comparator LM339D is used to monitor over-current signal, and its output 2 pin meet U
292 pin of-NE555, U
29-NE555 is connected into trigger to constitute signal holding circuit, and its 3 pin output is through diode D
16Be added to triode T
3Base stage.
Voltage of intermediate frequency instrument transformer output signal is through B
5Rectification, capacitor C
14, resistance R
35, R
36The direct current signal of exporting after the filtering is delivered to comparator LM339A-7 pin, compares after 1 pin outputs level signals to XOR gate CD4030A-1 pin, is passed through diode D simultaneously with 6 pin setting voltages
7Enter 2 pin; Power given potentiometer signal is delivered to comparator LM339B-11 pin, with the given voltage ratio of 10 pin after 13 pin outputs level signals to XOR gate CD4030A-2 pin, after logic determines, by 3 pin outputs level signals to the CD4030B-6 pin, 5 pin connect fixedly high level, make CD4030B constitute inverter, and the level signal of 4 pin output is delivered to 2 pin of NE555, NE555 is connected into trigger and constitutes signal holding circuit, and inhibit signal is exported by 3 pin.During abnormal conditions, 3 pin output high level passes through R
64, T
3Turn off the rectification control signal.
Fig. 5 is the inverter control circuit block diagram
Control system is that the control core is finished frequency-tracking, produced functions such as inverter control signal, building-out capacitor automatic switchover, fault-signal processing, input signal processing, output signal demonstration with the single-chip microcomputer.
Fig. 6 is an inverter control circuit
U among Fig. 6
21-LM339 is a voltage comparator, its end of oppisite phase 6 pin ground connection.The detected sine voltage signal of voltage transformer is through R
21Be added to in-phase input end 7 pin of comparator, antiparallel two diode D
2, D
3Be used to limit the input voltage amplitude.After relatively, export square wave voltage signal, through U by 1 pin
23Optocoupler 6N137 photoelectricity is isolated 14 pin of the electric sheet machine 89C51 of conversion back input, is used for the synchronizing signal of frequency-tracking and drive signal.
U
23Optocoupler TLP521-4, U
24A-C voltage comparator LM339 and auxiliary circuit thereof are used for the three-phase electricity open-phase protection.
U among Fig. 7
6Be eeprom chip X25045, U
7Be WATCHDOG chip DS1302.The P0.0-P0.3 port output IGBT control signal of single-chip microcomputer 89C51 is respectively through 6N137 optocoupler U
9-U
12Be added to four IGBT brachium pontis (V of inverter after the isolation drive
1, V
2, V
3, V
4) on.U
13Optocoupler TLP521-2 is used to detect the IGBT over-current signal, and its signal is added to U
812 pin.
M57962 is the IGBT integrated drive electronics among Fig. 8, and its 13 and 14 pin is a signal input part, and 5 pin are signal output part, pass through resistance R
4Be added to the G utmost point of IGBT, 1 pin is by fast recovery diode D
1Receive the C utmost point of IGBT, 8 pin are the over-current signal output.
The P2.0-P2.2 port of single-chip microcomputer 89C51 output shows signal among Fig. 9 is through U
16D-FAfter driver 74LS07 drives, through U
17-19Export after the optocoupler 6N137 isolation drive; The P2.4 port is through U
16ADriver 74LS07 drives, U
20After the optocoupler TLP521-2 isolation drive, be used to drive intermediate frequency contactor, carry out capacitor and switch.U
14, U
15Optocoupler is used for input and isolates.
MAX7219 is eight LED display drivers of serial ports among Figure 10, and its 1 pin is the serial data input, and 13 pin are input end of clock, resistance R
1Be used to control the drive current of LED.Its D
0-D
8Pin connects the position control end of LED charactron, and its SA-SG connects the section control end of LED charactron.The D of display part
0-D
7Be LED charactron, wherein D
0-D
3Be time showing, D
4-D
7For frequency shows; D
8-D
13Be the LED malfunction indicator lamp.
Claims (5)
1. variable frequency induction heater, form by power supply and body of heater two large divisions, power unit is wherein connect in proper order by rectification circuit, filter circuit, inverter circuit, load and forms, load is joined by inverter control circuit and inverter circuit, join by rectifier control circuit and rectification circuit simultaneously, it is characterized in that:
Described inverter circuit is by V
1, V
2, V
3, V
4Four inversion bridge circuits that IGBT forms, V
1/ V
4And V
2/ V
3Control alternate conduction respectively by inverter control circuit, bridge circuit output is added on the antiresonant circuit of inductive load L and building-out capacitor C composition by intermediate frequency transformer B;
The core of described inverter control circuit is the 89C51 single-chip microcomputer, and its voltage of intermediate frequency signal with detected inverter circuit output is an input signal, compares tracking with the trigger impulse phase place of exporting, and the trigger impulse of its output is by IGBT drive circuit control V
1/ V
4And V
2/ V
3Alternate conduction.
2. according to the described variable frequency induction firing equipment of claim 1, it is characterized in that: adopt integrated dephasing thyristor module ZLMK to constitute rectified three-phase circuit; Rectifier control circuit is made up of control and protection two parts; Threephase current transformer IM
1, IM
2, IM
3Output by with P
6The signal of current limit value relatively amplifies, through diode D
17Again with power given potentiometer P
7Output is at U
30DCarry out the synthetic formation of signal control circuit part among the TL084, its output connects the control end of rectification module ZLMK to regulate the rectification module output voltage; The output of voltage of intermediate frequency instrument transformer B and power given potentiometer P
7Output by XOR gate A
1Control triode T
3Base stage constitute protective circuit part, T
3Collector electrode and the control end of rectification module link.
3. according to claim 1 or 2 described variable frequency induction firing equipments, it is characterized in that: described isolating transformer B is many tapped transformers.
4. according to claim 1 or 2 described variable frequency induction firing equipments, it is characterized in that: described capacitor C is by its capacity of contact switching change of intermediate frequency contactor.
5. according to claim 1 or 2 described variable frequency induction firing equipments, it is characterized in that: described V
1, V
2, V
3, V
4Two ends parallel resistance R respectively
SC
SConstitute the RC resistance capaciting absorpting circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 99250636 CN2399898Y (en) | 1999-12-14 | 1999-12-14 | Frequency variable operation induction heating equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 99250636 CN2399898Y (en) | 1999-12-14 | 1999-12-14 | Frequency variable operation induction heating equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2399898Y true CN2399898Y (en) | 2000-10-04 |
Family
ID=34035334
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 99250636 Expired - Lifetime CN2399898Y (en) | 1999-12-14 | 1999-12-14 | Frequency variable operation induction heating equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2399898Y (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103024957A (en) * | 2012-12-31 | 2013-04-03 | 山东彼岸电力科技有限公司 | Medium-frequency induction heating power source and control method thereof |
| CN108239784A (en) * | 2018-03-23 | 2018-07-03 | 韶关保绿环保科技股份有限公司 | Zone melting furnace system |
| CN109202250A (en) * | 2018-11-23 | 2019-01-15 | 合肥国声电子通信有限责任公司 | A kind of Intelligent welding control system and method |
| CN117156620A (en) * | 2023-10-31 | 2023-12-01 | 上海盛迪瓦特电气有限公司 | High-reliability current source type induction heating power supply system and device |
-
1999
- 1999-12-14 CN CN 99250636 patent/CN2399898Y/en not_active Expired - Lifetime
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103024957A (en) * | 2012-12-31 | 2013-04-03 | 山东彼岸电力科技有限公司 | Medium-frequency induction heating power source and control method thereof |
| CN108239784A (en) * | 2018-03-23 | 2018-07-03 | 韶关保绿环保科技股份有限公司 | Zone melting furnace system |
| CN109202250A (en) * | 2018-11-23 | 2019-01-15 | 合肥国声电子通信有限责任公司 | A kind of Intelligent welding control system and method |
| CN117156620A (en) * | 2023-10-31 | 2023-12-01 | 上海盛迪瓦特电气有限公司 | High-reliability current source type induction heating power supply system and device |
| CN117156620B (en) * | 2023-10-31 | 2024-01-30 | 上海盛迪瓦特电气有限公司 | High-reliability current source type induction heating power supply system and device |
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