CN101386099A - Soft-switch invert welding power numerical control method of electric welding machine - Google Patents
Soft-switch invert welding power numerical control method of electric welding machine Download PDFInfo
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- CN101386099A CN101386099A CNA2008102018521A CN200810201852A CN101386099A CN 101386099 A CN101386099 A CN 101386099A CN A2008102018521 A CNA2008102018521 A CN A2008102018521A CN 200810201852 A CN200810201852 A CN 200810201852A CN 101386099 A CN101386099 A CN 101386099A
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- pulse
- comparing unit
- numerical control
- welding power
- power source
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
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Abstract
The invention relates to a soft switch inverter welding power numerical control method used for an electric welder; firstly, a first pulse, a second pulse, a third pulse and a fourth pulse are output; subsequently, the first pulse and the second pulse are respectively output to two inverter switch pipes of leading bridge; the third pulse and the fourth pulse are respectively output to two inverter switch pipes of lagging bridge; furthermore, establishment of empty-load voltage, invariableness of loaded current and adjustment of thrust current are finished before cyclic interrupt; comparing register value of a first full-comparing unit and a second full-comparing unit is continuously modified in underflow interrupt and cyclic interrupt according to the output requirement of the adjuster; the method effectively reduces the on/off loss of the switch pipe, improves the switching frequency, reduces the complexity of the controller design, greatly improves the smartness, has high control precision and good reliability and can better realize the switching even under small loads.
Description
Technical field
The present invention relates to a kind of inversion welding source control method technical field, particularly soft switch inverter welding power source control method technical field, specifically be meant a kind of soft switch inverter welding power source numerical control method of electric welding machine.
Background technology
Contravariant arc welding power source is because therefore little, the light weight of volume, energy-efficient and function admirable obtained extensive studies.But switching frequency is too high in the contravariant arc welding power source, and electric current is excessive, and this just exists bigger switching loss, and EMI is excessive simultaneously.One of focus of soft switch conduct Power Electronic Technique research has at present solved this problem well.
In recent years, along with the development of components and parts such as single-chip microcomputer, digital signal processor and CPLD, digital control technology is widely used.With respect to traditional simulation control, digital control technology has that control method is flexible and changeable, control accuracy is high, the reliability advantages of higher.The state-of-the-art technology trend of Arc Welding Power is exactly that inversion soft switch technique and digital control technology combine both at home and abroad at present.
Summary of the invention
The object of the present invention is to provide a kind of soft switch inverter welding power source numerical control method of electric welding machine, effectively reduce the turn-off power loss of opening of switching tube, improved switching frequency, reduced the complexity of controller design, control accuracy height, good reliability improved its flexibility greatly, even also can be realized soft switch preferably under less load.
To achieve the above object, the invention provides a kind of soft switch inverter welding power source numerical control method of electric welding machine, it comprises step:
The soft switch inverter welding power source numerical control method of this electric welding machine is characterized in, comprises step:
1) the first full comparing unit of the digital processing unit by numerical control system is exported first pulse and second pulse, and the second full comparing unit is exported the 3rd pulse and the 4th pulse;
2) described first pulse and described second pulse are delivered to two inverse switch pipes of the leading-bridge of soft switch inverter welding power source, and described the 3rd pulse and described the 4th pulse are delivered to two inverse switch pipes of the lagging leg of soft switch inverter welding power source;
3) in cycle interruption, finish the soft start of floating voltage, read the electric current and voltage sampled value, realize switchings unloaded and two kinds of different operating modes of load by detecting output current, under two kinds of different operating modes, implement work such as control algolithm separately, finish the adjusting of constant and push current of foundation, the load current of floating voltage;
4) the comparand register numerical value of the first full comparing unit and the second full comparing unit is constantly revised in the middle of underflow interruption and cycle interruption according to the requirement of adjuster output.
Preferably, in step 3), described modification is that tax gives the comparand register of the first full comparing unit and the second full comparing unit at rolling counters forward trailing edge fiducial value in underflow is interrupted, the comparand register that the first full comparing unit and the second full comparing unit are given in tax in cycle interruption is at rolling counters forward rising edge fiducial value, and wherein the rolling counters forward cycle is the pulse period.
Preferably, also comprise step: 5) described numerical control system is gathered fault-signal, and the generation signal goes locking pulse to amplify and shaping circuit, produce the PDPINTA signal simultaneously and send digital signal processor, send the inner PDPINTA of generation of digital signal processor interrupt disable pulse output, thereby interrupt inversion welding source.
More preferably, described fault-signal comprises output over-voltage overcurrent, dc bus overcurrent, imported/under-voltage or one or more overheated signals of machine.
Adopted the soft switch inverter welding power source numerical control method of electric welding machine of the present invention, soft switch adopts the contravariant arc welding power source of phase-shifting full-bridge ZVZCSPWM converter, utilize clamping capacitance to realize the ZVS of leading-bridge, utilize saturated resonant inductance to realize the ZCS of lagging leg, reduce the turn-off power loss of opening of switching tube effectively, improved switching frequency; The introducing of numerical control system has not only reduced the complexity of controller design, and has improved its flexibility greatly.Soft-switching inversion arc-welding machine according to above-mentioned principle design proves functional by experiment.
Description of drawings
Fig. 1 is the main circuit schematic diagram of the ZVZCS converter of the band pulsactor that adopts in the specific embodiment of the present invention.
Fig. 2 is the phase-shift pulse generating principle figure of a specific embodiment of the present invention.
Fig. 3 is the main program flow chart of a specific embodiment of the present invention.
The specific embodiment
Below will be described in further detail real-time recording method of welder performance of the present invention.
See also Fig. 1～shown in Figure 3, the soft switch inverter welding power source numerical control method of this electric welding machine of the present invention comprises step:
1) the first full comparing unit of the digital processing unit by numerical control system is exported first pulse and second pulse, and the second full comparing unit is exported the 3rd pulse and the 4th pulse;
2) described first pulse and described second pulse are delivered to two inverse switch pipes of the leading-bridge of soft switch inverter welding power source, and described the 3rd pulse and described the 4th pulse are delivered to two inverse switch pipes of the lagging leg of soft switch inverter welding power source;
3) in cycle interruption, finish the soft start of floating voltage, read the electric current and voltage sampled value, realize switchings unloaded and two kinds of different operating modes of load by detecting output current, under two kinds of different operating modes, implement work such as control algolithm separately, finish the adjusting of constant and push current of foundation, the load current of floating voltage;
4) the comparand register numerical value of the first full comparing unit and the second full comparing unit is constantly revised in the middle of underflow interruption and cycle interruption according to the requirement of adjuster output.
Preferably, in step 3), described modification is that tax gives the comparand register of the first full comparing unit and the second full comparing unit at rolling counters forward trailing edge fiducial value in underflow is interrupted, the comparand register that the first full comparing unit and the second full comparing unit are given in tax in cycle interruption is at rolling counters forward rising edge fiducial value, and wherein the rolling counters forward cycle is the pulse period.
Preferably, also comprise step: 5) described numerical control system is gathered fault-signal, and the generation signal goes locking pulse to amplify and shaping circuit, produce the PDPINTA signal simultaneously and send digital signal processor, send the inner PDPINTA of generation of digital signal processor interrupt disable pulse output, thereby interrupt inversion welding source.
More preferably, described fault-signal comprises output over-voltage overcurrent, dc bus overcurrent, imported/under-voltage or one or more overheated signals of machine.
Soft switch inverter welding power source of the present invention adopts the phase-shifting full-bridge ZVZCS pwm converter of band pulsactor.
In phase-shifting full-bridge ZVZCS pwm converter, the no-voltage of leading-bridge (ZVS) switch is to realize at the in parallel suitable electric capacity of leading-bridge, and lagging leg will realize that zero current (ZCS) switch must be during transformer primary voltage zero passage, make primary current reset-to-zero and of short duration pincers at zero current, this generally also needs to add auxiliary circuit, as band pulsactor, subcarrier band clamp etc.
By analyzing, take all factors into consideration factors such as efficient, cost and realization complexity, the topology that the present invention selects to utilize pulsactor to realize lagging leg ZCS is as main circuit.
The band pulsactor phase-shifting full-bridge ZVZCS pwm converter main circuit as shown in Figure 1, leading-bridge (IGBT
1And IGBT
3The brachium pontis of forming) realizes ZVT, lagging leg (IGBT
2And IGBT
4The brachium pontis of forming) realizes Zero Current Switch, thereby realized the zero-voltage and zero-current switch (ZVZCS) of soft-switching inversion welding machine, VD
1～VD
4Be respectively and IGBT
1～IGBT
4Two switching tube (IGBT on each brachium pontis of the diode of reverse parallel connection
1And IGBT
3Or IGBT
2And IGBT
4) conducting half period in turn.Thereby introduce the dutycycle that phase shift determines converter between two brachium pontis.
Its operation principle is: close at IGBT of leading arm and have no progeny, main circuit enters the nature commutation process, at this moment saturation reactance L
sStill be in saturation state, transformer primary current i
pAt capacitance C
bWith main transformer primary side leakage reactance L
LkResonance effect descend down rapidly.Work as i
pWhen dropping to zero, because saturation reactance L
sWithdrawed from saturatedly, stoped blocking capacitor crest voltage U
CbpThe reverse direction current flow that causes, thus the shutoff of lagging leg is finished under the zero-voltage zero-current state.Subsequently, the another IGBT pipe on the lagging leg is open-minded, supply voltage U
InWith U
CbpSum is added on the saturation reactance, because saturation reactance enters of short duration process of saturated needs, electric current can not rise immediately, and opening of lagging leg also is to finish under zero current like this.
1. main circuit parameter design:
1.1 the design of main transformer
Transformer voltage ratio
K＝U
in(min)D
p(max)/(U
o/D
sec(max)) (1)
The first side winding number of turn
N
1＝U
in(min)×10
8/(K
fB
mfS
C) (2)
The secondary side winding number of turn
N
2＝N
3＝N
1/K (3)
U in the formula
In (min)Minimum of a value for input voltage; D
P (max)Be the primary side maximum duty cycle; D
Sec (max)Be the secondary side maximum duty cycle; U
oBe rated output voltage; K
fBe form factor, get 4.44 when sinusoidal, get 4 during square wave; B
mBe the close (unit: Gs) of high workload magnetic of selected magnetic core; F is a switching frequency (unit: Hz); S
CBe magnetic core net sectional area (unit: cm
2).
1.2 the design of leading-bridge shunt capacitance
Shunt capacitance
C
1＝C
3≤I
o(min)td
(lead)/(2KU
in(max)) (4)
I in the formula
O (min)Be minimum output current; U
In (max)Be maximum input voltage; Td
(lead)Be the Dead Time between the leading-bridge two switching tubes driving signal.
1.3 the design of pulsactor
The pulsactor voltagesecond product
Φ
Ls＝U
Cbp·T
ZC＝U
Cbp(T/2-DT/2-ΔT) (5)
U in the formula
CbpBe the blocking capacitor crest voltage; T
ZCBe the lagging leg Zero Current Switch time; Δ T is a circulation time.
1.4 the design of blocking capacitor
Blocking capacitor
C
b＝nI
o·(DT
2-D
2T
2)/(8(Φ
Ls+nI
oL
lk) (6)
Φ in the formula
LsBe the pulsactor voltagesecond product, for known; L
LkBe transformer leakage inductance.
1.5 the design of output inductor
Output inductor
L
f＝U
o(min)/(2·2f·5％I
o(max))(1-U
o(max)/(U
in(min)/k-U
Lf-U
D)) (7)
F is the operating frequency of output inductor in the formula; U
LfBe voltage drop on the filter inductance; U
DFor the commutation diode conducting voltage is fallen.
2. the design of control circuit
2.1 the implementation method of phase-shift PWM ripple
Basic principle is: utilize two full comparing units in the DSP task manager to export four tunnel pulses.Export leading arm by the first full comparing unit and manage pulse up and down, the second full comparing unit lag output arm is managed pulse up and down.The comparand register numerical value of two full comparing units is constantly revised in the middle of underflow interruption and cycle interruption according to the requirement of adjuster output, as shown in Figure 2.In underflow is interrupted, compose and give CMPR1﹠amp; CMPR2 composes in cycle interruption and gives CMPR1﹠amp at rolling counters forward trailing edge fiducial value; CMPR2 is at rolling counters forward rising edge fiducial value.The rolling counters forward cycle is the pulse period.During actual program, need be according to the method to set up setting of relatively exporting doublet impulse entirely.
2.2 the software flow of numerical control system
Systems soft ware has main program and interrupt routine two large divisions, and main program (seeing shown in Figure 3) mainly is to finish system initialization, switching on and shutting down detection, switching on and shutting down initialization, enters the main program circular wait then and interrupts.The common construction system interrupt routine of cycle interruption program, underflow interrupt routine and PDPINTA program.
In the cycle interruption program, finish the soft start of floating voltage, read the electric current and voltage sampled value, realize switchings unloaded and two kinds of different operating modes of load, under two kinds of different operating modes, implement work such as control algolithm separately by detecting output current.Finish the adjusting of constant and push current of foundation, the load current of floating voltage in the cycle interruption.
The underflow interrupt routine is used for upgrading the value of CMPR1 and CMPR2.
When main circuit breaks down, as output over-voltage overcurrent, dc bus overcurrent, imported/under-voltage and machine are overheated etc., external hardware produces signal and goes locking pulse to amplify and shaping circuit, produce the PDPINTA signal simultaneously and send DSP, the pulse of the inner PDPINTA of generation of DSP interrupt disable is exported.
Design a 250A/10kW contravariant arc welding power source by above method, be input as three-phase 380V ± 15%, output floating voltage 70V, maximum output welding current 250A, controller adopts the dsp chip TMS320LF2407 of TI company.The proof power source performance is good.
Therefore, phase-shifting full-bridge ZVZCS pwm converter of the present invention utilizes clamping capacitance to realize the ZVS of leading-bridge, utilizes saturated resonant inductance to realize the ZCS of lagging leg, and the turn-off power loss of opening that it has reduced switching tube has effectively improved switching frequency; The introducing of numerical control system has not only reduced the complexity of controller design, and has improved its flexibility greatly.
In sum, the soft switch inverter welding power source numerical control method of electric welding machine of the present invention effectively reduces the turn-off power loss of opening of switching tube, improved switching frequency, reduced the complexity of controller design, control accuracy height, good reliability improved its flexibility greatly, even also can be realized soft switch preferably under less load.
In this specification, the present invention is described with reference to its certain embodiments.But, still can make various modifications and conversion obviously and not deviate from the spirit and scope of the present invention.Therefore, specification and accompanying drawing are regarded in an illustrative, rather than a restrictive.
Claims (4)
1. the soft switch inverter welding power source numerical control method of an electric welding machine is characterized in that, comprises step:
1) the first full comparing unit of the digital processing unit by numerical control system is exported first pulse and second pulse, and the second full comparing unit is exported the 3rd pulse and the 4th pulse;
2) described first pulse and described second pulse are delivered to two inverse switch pipes of the leading-bridge of soft switch inverter welding power source, and described the 3rd pulse and described the 4th pulse are delivered to two inverse switch pipes of the lagging leg of soft switch inverter welding power source;
3) in cycle interruption, finish the soft start of floating voltage, read the electric current and voltage sampled value, realize switchings unloaded and two kinds of different operating modes of load by detecting output current, under two kinds of different operating modes, implement work such as control algolithm separately, finish the adjusting of constant and push current of foundation, the load current of floating voltage;
4) the comparand register numerical value of the first full comparing unit and the second full comparing unit is constantly revised in the middle of underflow interruption and cycle interruption according to the requirement of adjuster output.
2. the soft switch inverter welding power source numerical control method of electric welding machine as claimed in claim 1, it is characterized in that, in step 3), described modification is that tax gives the comparand register of the first full comparing unit and the second full comparing unit at rolling counters forward trailing edge fiducial value in underflow is interrupted, the comparand register that the first full comparing unit and the second full comparing unit are given in tax in cycle interruption is at rolling counters forward rising edge fiducial value, and wherein the rolling counters forward cycle is the pulse period.
3. the soft switch inverter welding power source numerical control method of electric welding machine as claimed in claim 1, it is characterized in that, also comprise step: 5) described numerical control system is gathered fault-signal, and the generation signal goes locking pulse to amplify and shaping circuit, produce the PDPINTA signal simultaneously and send digital signal processor, send the inner PDPINTA of generation of digital signal processor interrupt disable pulse output, thereby interrupt inversion welding source.
4. the soft switch inverter welding power source numerical control method of electric welding machine as claimed in claim 3 is characterized in that, described fault-signal comprises output over-voltage overcurrent, dc bus overcurrent, imported/under-voltage or one or more overheated signals of machine.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2008102018521A CN101386099A (en) | 2008-10-28 | 2008-10-28 | Soft-switch invert welding power numerical control method of electric welding machine |
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|---|---|---|---|
| CNA2008102018521A CN101386099A (en) | 2008-10-28 | 2008-10-28 | Soft-switch invert welding power numerical control method of electric welding machine |
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| CN101386099A true CN101386099A (en) | 2009-03-18 |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101618472B (en) * | 2009-08-06 | 2012-07-04 | 唐山松下产业机器有限公司 | Soft switching inversion welding machine |
| CN102784999A (en) * | 2012-08-31 | 2012-11-21 | 苏州市双马机电有限公司 | Two-transistor forward soft-switching inverter manual electric arc welder |
| CN110557022A (en) * | 2018-05-31 | 2019-12-10 | 华为技术有限公司 | Method for controlling PSFB converter and PSFB converter |
| CN110729912A (en) * | 2019-10-30 | 2020-01-24 | 渤海大学 | High-frequency induction heating series resonance soft switch inversion control method |
| CN112769335A (en) * | 2021-02-26 | 2021-05-07 | 许继电源有限公司 | Output current control method and system for multiphase interleaving parallel DC-DC converter |
| CN114900027A (en) * | 2022-07-14 | 2022-08-12 | 阳光电源股份有限公司 | Converter and wave-sealing control method thereof |
| CN115106635A (en) * | 2022-07-14 | 2022-09-27 | 深圳市海浦蒙特科技有限公司 | DSP controller and constant current control method and device of medium-frequency inverter welding power supply |
-
2008
- 2008-10-28 CN CNA2008102018521A patent/CN101386099A/en active Pending
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101618472B (en) * | 2009-08-06 | 2012-07-04 | 唐山松下产业机器有限公司 | Soft switching inversion welding machine |
| CN102784999A (en) * | 2012-08-31 | 2012-11-21 | 苏州市双马机电有限公司 | Two-transistor forward soft-switching inverter manual electric arc welder |
| CN110557022A (en) * | 2018-05-31 | 2019-12-10 | 华为技术有限公司 | Method for controlling PSFB converter and PSFB converter |
| US10784786B2 (en) | 2018-05-31 | 2020-09-22 | Huawei Technologies Co., Ltd. | PSFB converter and methods for controlling a PSFB converter |
| CN110729912A (en) * | 2019-10-30 | 2020-01-24 | 渤海大学 | High-frequency induction heating series resonance soft switch inversion control method |
| CN110729912B (en) * | 2019-10-30 | 2021-05-14 | 渤海大学 | High-frequency induction heating series resonance soft switch inversion control method |
| CN112769335A (en) * | 2021-02-26 | 2021-05-07 | 许继电源有限公司 | Output current control method and system for multiphase interleaving parallel DC-DC converter |
| CN112769335B (en) * | 2021-02-26 | 2022-08-19 | 许继电源有限公司 | Output current control method and system for multiphase interleaved parallel DC-DC converter |
| CN114900027A (en) * | 2022-07-14 | 2022-08-12 | 阳光电源股份有限公司 | Converter and wave-sealing control method thereof |
| CN115106635A (en) * | 2022-07-14 | 2022-09-27 | 深圳市海浦蒙特科技有限公司 | DSP controller and constant current control method and device of medium-frequency inverter welding power supply |
| CN114900027B (en) * | 2022-07-14 | 2022-11-15 | 阳光电源股份有限公司 | Converter and wave-sealing control method thereof |
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Open date: 20090318 |