CN2185175Y

CN2185175Y - Power for inverted type cutting-welding machine

Info

Publication number: CN2185175Y
Application number: CN93247855U
Authority: CN
Inventors: 冯沛; 潘天明; 朱必军; 曾巍
Original assignee: Beijing General Research Institute for Non Ferrous Metals
Current assignee: Beijing General Research Institute for Non Ferrous Metals
Priority date: 1993-12-21
Filing date: 1993-12-21
Publication date: 1994-12-14
Anticipated expiration: 2003-12-21

Abstract

The utility model belongs to a power supply for inverted type cutting-welding machines, comprising an input rectifier, an inverter, a high-frequency transformer, an output rectifier, an electric reactor and an electronic control circuit. Because an industrial-frequency power supply is changed into high frequency alternating current by rectification and inversion and is provided with voltage reduction, the weight and the volume of the whole machine of the power supply can be reduce; simultaneously, reactive power loss is reduced; power factor is improved. An inverter circuit is in the state of stop and no-load loss can be eliminated when not cut and welded.

Description

Power for inverted type cutting-welding machine

The utility model belongs to the power supply that contravariant is cut the weldering multiple purpose aeroplane.

The power supply of generally cutting the weldering multiple purpose aeroplane all be earlier the power supply in 380 volts of three-phases, 50 weeks through the transformer step-down, behind rectifying and wave-filtering, form the dc source of cutting and welding again, the major defect of this power supply is that 1. Industrial Frequency Transformer weight are big, volume is big, so the weight and volume of complete machine is also big, 2. copper loss and iron loss are big, energy consumption is high.

The purpose of this utility model be to design a kind of in light weight, volume is little, the contravariant of energy saving cut the weldering multiple purpose aeroplane power supply.

The power supply that the contravariant of the utility model design is cut the weldering multiple purpose aeroplane comprises transformer, rectifier, inverter and electronic control circuit, wherein transformer is a high frequency transformer, rectifier comprises input rectifier and output rectifier, input rectifier, inverter, high frequency transformer, output rectifier connect successively, electronic control circuit then comprises drive circuit, current feedback circuit, pulse width modulator, given circuit, the output of drive circuit wherein is connected with inverter, and its operation principle is once to hold 380 volt of 50 all alternating current of input three-phase; After rectification and filtering, be transformed into direct current, form inverter circuit with high power transistor, DC converting is become high-frequency ac, the high frequency voltage that inversion is obtained by high frequency transformer drops to welding, the required low-voltage of cutting, obtain stable low-voltage direct output through rectification again and supply with electric arc, by the output of pulsewidth modulation method control impuls waveform, the characteristic of high-speed response to realize precision.

Cut in the power supply of weldering multiple purpose aeroplane at designed contravariant, inverter adopts half bridge circuit, and it is made up of the former limit of two electric capacity and high frequency transformer, and inverter transistor adopts insulated gate bipolar transistor.

Start dash current in order to alleviate cutting, in current feedback circuit, also have reactor.

In order further to reduce machine volume and weight, can use high frequency to cut the weldering transformer.

Transformer in the design's power supply is the high-frequency alternating current transformation that obtains through rectification and inversion, its operating frequency can be the hundred times of power frequency (50Hz), so core section is long-pending and coil can significantly reduce, thereby the weight and volume of power supply complete machine is reduced greatly, approximately can alleviate and narrow down to originally 1/10th, simultaneously, copper loss and iron loss also can reduce along with the minimizing of material, reactive loss also reduces, the corresponding raising of power factor; Inverter circuit can be accomplished the three-phase load complete equipilibrium in addition, so input power can reduce, and when cutting the weldering state, inverter circuit is in halted state, has eliminated open circuit loss non-.

Fig. 1 is the circuit block diagram that the contravariant of the utility model design is cut the power supply of weldering multiple purpose aeroplane.

Fig. 2 is the fundamental diagram that adopts semi-bridge type inverter, produces positive pulse.

Fig. 3 is the fundamental diagram that adopts semi-bridge type inverter, produces negative pulse.

Fig. 4 is the schematic diagram of electronic control circuit.

Fig. 5 is the line map that the contravariant of the utility model design is cut the power supply of weldering multiple purpose aeroplane.

Below in conjunction with accompanying drawing embodiment of the present utility model and effect thereof are further described.

Fig. 1 is the circuit block diagram that the contravariant of the utility model design is cut the power supply of weldering multiple purpose aeroplane, it is made up of input rectifier 1, inverter 2, high frequency transformer 3, output rectifier 4, reactor 5 and electronic control circuit 6, and Fig. 5 is a kind of line map that contravariant is cut the power supply of weldering multiple purpose aeroplane.Fig. 4 cuts the schematic diagram of the electronic control circuit of the power supply that welds multiple purpose aeroplane for this contravariant; wherein input rectifier can adopt the 6RL75G-120 that adopts three phase full wave rectification among the existing various rectification circuit figure; R27; R28; R29 is a piezo-resistance; shield; inverter 2 can adopt bridge-type or half bridge circuit; the inverter of the employing series connection half bridge circuit that provides among the figure; it is by two inverter transistors; the former limit of two electric capacity and high frequency transformer is formed; half bridge circuit is simple; the commutation loss is little; the inversion efficiency height; because cutting zero load and operating voltage are 4 times of weldingvoltage; high-frequency arc strike in addition; inverter transistor damages easily; for eliminating destructive interference to inverter transistor; except that output loop with capacitance-resistance filter; also need be at high frequency transformer input connecting resistance R22; capacitor C 9; in the work; when inverter transistor T1 leads to; when T2 breaks; power supply gives capacitor C 12 chargings through T1 and high-frequency electrical depressor B; C10 is through T1 and B discharge simultaneously; its current i c1; ic2 passes through B to the right, and iB=iC1+iC2 forms a positive pulse (see figure 2) in primary.Power supply is through B when the disconnected T2 of T1 is logical; T2 charges to C10; C12 is through T2 simultaneously; the B discharge; its current i c1; ic2 passes through B left; opposite to last direction negative pulse (see figure 3) of primary formation; like this; T1; T2 replaces break-make; just at elementary formation of transformer B and T1; T2 replaces the identical high-frequency and high-voltage of break-make frequency and exchanges; the high-voltage alternating of 20KHz for example; T1 and T2 adopt the IGBT insulating grid bipolar transistor modular block capable; high frequency transformer B adopts the step-down form; high frequency low voltage is fallen in the interchange of the high-frequency and high-voltage of primary coil to be exchanged; because former side frequency is a high frequency; 20KHz for example; so the core section A of transformer and turn number N are all dwindled greatly than the general transformer of 50Hz; from computing formula as can be known; NA can be reduced to original 1/400; and copper loss; iron loss; reactive loss also all reduces thereupon; the corresponding raising of power factor; high frequency transformer can be two; be respectively applied for cutting and welding; cutting; it is that high frequency is cut the weldering transformer that welding also can be adopted same high frequency transformer; to reduce the volume and weight of complete machine; as use FERRITE CORE MX-2000; E36; be applicable to cutting or welding respectively by cutting the weldering selector switch; output rectifier is that the alternating current that will become high frequency low voltage becomes the DC voltage that can supply welding or cutting through rectification; output rectifier can be selected various rectification circuits for use; what provide among the figure is the double half-wave rectification circuit; form by two fast recovery diode D3 and D4; the advantage of sort circuit is easy for installation; the material saving; so can alleviate complete machine weight; electronic control circuit is by the IC1 pulse width modulator; IC2; the IC3 driver; the IC4 current protecting circuit; R is given; M current feedback sensor is formed; give given current potential of pulse width modulator IC1 by regulating given potentiometer R3; to set the width of IC1 output pulse; the pulse frequency of IC1 output is fixed; pulse is wide; then the IGBT ON time is just long; give the transformer output voltage just high; otherwise the IGBT ON time is just short; output voltage is just low; current sensor M can select hall device for use; the welding cutting current is the operating current formation Current Negative Three-Point Capacitance closed-loop control by current sensor senses; keep and cut the constant of weldering electric current; driver IC 2; IC3 selects IGTBT special driver EXB841 for use; during overcurrent; by IC4 IC1 pulse output is cut off and made the output of entire circuit no current; protection IGBT is not damaged; add reactor 5 in the power supply and can alleviate cutting startup dash current; and make cutting and welding current level and smooth; thereby make little electric current cutting and welding all very reliable and stable; the design's contravariant is cut the power supply of weldering multiple purpose aeroplane when being used for multiple purpose aeroplane; answer configuring high-frequency striking device at output, between high frequency transformer and output rectifier, should dispose and cut the weldering selector switch.

Claims

1, a kind of contravariant is cut the power supply of weldering multiple purpose aeroplane, comprise transformer, rectifier, inverter and electronic control circuit, it is characterized in that said rectifier comprises input rectifier and output rectifier, said transformer is a high frequency transformer, said input rectifier, inverter, high frequency transformer, output rectifier connect successively, said electronic control circuit comprises drive circuit, current feedback circuit, pulse width modulator, given circuit, the output of said drive circuit is connected with inverter.

2, cut the power supply of weldering multiple purpose aeroplane according to the said a kind of contravariant of claim 1, it is characterized in that said inverter adopts half bridge circuit, it is made up of the former limit of two inverter transistors, two electric capacity and high frequency transformer, and said inverter transistor adopts insulated gate bipolar transistor.

3, cut the power supply that welds multiple purpose aeroplane according to claim 1 or 2 said a kind of contravariants, it is characterized in that also having in the said current feedback circuit reactor.

4, cut the power supply of weldering multiple purpose aeroplane according to the said a kind of contravariant of claim 3, it is characterized in that said high frequency transformer is that high frequency is cut the weldering transformer.