CN201002164Y - An IGBT inverter DC pulse argon arc welding power supply - Google Patents

Abstract

The utility model discloses an IGBT inverter DC pulse argon arc welding power supply, which comprises a chassis and a built-in circuit. The built-in circuit includes a main circuit and a current feedback control circuit. The main circuit includes a rectification and filtering module, a high-frequency inverter The voltage module and the rectification and smoothing module are connected in sequence, and the current feedback control circuit includes a current and voltage detection module, a pulse parameter setting module, a comparator, a single-chip microcomputer control module, a pulse width modulation module and a high-frequency drive module. The utility model adopts a single-chip microcomputer for detection and feedback, and is used to realize peripheral monitoring and man-machine dialogue, so that the panel operation of the power supply is more convenient and humanized. The utility model adopts the high frequency arc striking module to control the arc striking and realizes the non-contact arc striking. The current frequency of the utility model is greatly improved, the volume and quality of the transformer are greatly reduced, the control becomes more sensitive, and the dynamic characteristics are greatly improved.

Description

An IGBT inverter DC pulse argon arc welding power supply

technical field

The utility model relates to the technical field of high frequency inverter, in particular to an IGBT inverter DC pulse argon arc welding power supply.

Background technique

At present, in the field of welding power sources, due to the large current and high power required by the process, the traditional DC and pulse argon arc welding power sources at home and abroad are mainly silicon rectifier and thyristor rectifier. The rectifier power supply is relatively reliable and technically It is also relatively mature, but the equipment is bulky, heavy, high energy consumption, low efficiency, and due to its structural reasons, its dynamic and static characteristics are not ideal.

Contents of the invention

The purpose of this utility model is to provide an IGBT inverter DC pulse argon arc welding power supply in order to solve the above-mentioned shortcomings in the prior art. The power supply has the advantages of simple structure, small size, small mass, energy saving and good dynamic characteristics.

The purpose of the utility model is achieved through the following technical solutions: the IGBT inverter DC pulse argon arc welding power supply includes a chassis and a built-in circuit, and the built-in circuit includes a main circuit and a current feedback control circuit, and the main circuit includes A rectification and filtering module, a high-frequency inverter module, a power transformation module and a rectification and smoothing module are connected in sequence, the rectification and filtering module is externally connected to a three-phase AC input power supply, and the rectification and smoothing module is externally connected to a load; the current feedback control circuit (i.e. The outer loop average current closed-loop control circuit) consists of a current and voltage detection module, a pulse parameter given module, a comparator, a single-chip microcomputer control module, a pulse width modulation module and a high-frequency drive module, and one end of the current and voltage detection module is connected to the load , the other end is connected to the input end of the comparator, the pulse parameter given module is connected to the other input end of the comparator, and the output end of the comparator is connected to the single-chip microcomputer control module and the pulse width modulation module respectively, The single-chip microcomputer control module is connected with the pulse width modulation module, the pulse width modulation module is connected with the high-frequency drive module, and the high-frequency drive module is connected with the high-frequency inverter module; the single-chip microcomputer control module is respectively connected with High-frequency arc ignition module and man-machine dialogue panel.

In order to better realize the utility model, the main circuit includes a safety protection circuit, and the safety protection circuit includes a network voltage detection module, a voltage protection module, a temperature detection module, and an overheat protection module; one end of the network voltage detection module is connected to The three-phase AC power supply is connected, and the other end is connected with the voltage protection module, and the voltage protection module is respectively connected with the pulse width modulation module and the single-chip microcomputer control module; one end of the temperature detection module is connected with the high-frequency inverter module, and the other end is connected with the high-frequency inverter module. One end is connected with the overheat protection module, and the overheat protection module is connected with the pulse width modulation module; the single-chip microcomputer control module is mainly composed of single-chip microcomputer PALCE22V10H, logic circuit chip ULN2003A and its peripheral circuits; the pulse width modulation module is mainly composed of error amplifier circuit , Integrated control chip SG3525 and its peripheral circuits.

The design principle of the utility model is as follows: the utility model adopts the inverter technology to greatly increase the frequency of the power supply, so that the volume and quality of the main transformer in the power supply are greatly reduced, and at the same time, because the electronic power device works on the switch State, transformers, etc. can use magnetic core materials with small iron loss, so the efficiency is very high. Due to the existence of capacitance in the main circuit, the power factor is greatly improved, and the energy saving effect is obvious. And because the operating frequency is very high, the filter inductance value in the main circuit is small, the electromagnetic inertia is small, and it is easy to obtain good dynamic characteristics. In addition, the inverter cutting power supply adopts inverter technology, which makes it sensitive and controllable. The utility model is an inverter direct current, pulse argon arc welding power supply, the main circuit adopts a half-bridge topology or a full-bridge inverter topology, depending on the power. And arc striking adopts high-frequency arc striking. The pulse width modulation is amplified by the error amplifier, and then compared with the reference given value to generate two sets of mutually push-pull drive signals to control the power inverter switching tube IGBT to be turned on and off according to a certain sequence to realize DC to AC conversion . Current feedback is to use Hall element to detect the output current at the load current output terminal, and obtain the sampling signal, which is amplified and compared, and then sent to the pulse width modulation module to change the conduction and cut-off time of the power tube and realize the adjustment of the duty cycle And the purpose of power regulation, so that the output energy is stable.

Compared with the prior art, the utility model has the following advantages and beneficial effects:

1. The utility model uses a single-chip microcomputer for detection and feedback, and is used to realize peripheral monitoring and man-machine dialogue, making the panel operation of the power supply more convenient and more humane.

2. The utility model adopts the high-frequency arc striking module to control the arc striking to realize the non-contact arc striking.

3. The utility model adopts a high-power switch tube and a pulse width modulation chip to realize the transformation of DC and AC, so that the current frequency is greatly increased, the volume and quality of the transformer are greatly reduced, the control becomes more sensitive, and the dynamic characteristics are improved. Great improvement. In short, a qualitative leap has taken place in the overall performance of the welding power source.

Description of drawings

Fig. 1 is a built-in circuit block diagram of the utility model;

Fig. 2 is a schematic diagram of the main circuit of the utility model;

Fig. 3 is the circuit schematic diagram of the pulse width modulation module and the high frequency drive module of the present invention;

Fig. 4 is the circuit schematic diagram of the single-chip microcomputer control module of the present utility model;

Fig. 5 is a schematic circuit diagram of the high-frequency arc striking module of the present invention;

Fig. 6 is the circuit schematic diagram of the high-frequency inverter module of the present invention;

Fig. 7 is a schematic circuit diagram of the rectifying and filtering module of the present invention.

Detailed ways

The utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments, but the implementation of the utility model is not limited thereto.

An IGBT inverter type DC pulse argon arc welding power source described in the utility model includes a chassis and a built-in circuit, as shown in FIG. 1 , the built-in circuit includes a main circuit and a current feedback control circuit. The main circuit is composed of a rectification and filtering module 101, a high frequency inverter module 102, a power transformation module 103 and a rectification and smoothing module 104 connected in sequence. The rectification and filtering module 101 is connected with the three-phase AC input power supply, and the rectification and smoothing module 104 is connected with the load phase connect. The current feedback control circuit includes a current and voltage detection module 112, a pulse parameter setting module 117, a comparator, a single-chip microcomputer control module 107, a pulse width modulation module 108 and a high-frequency drive module 109. One end of the current and voltage detection module 112 is connected to the load , the other end is connected with the input end of the comparator, the pulse parameter given module is connected with the other input end of the comparator, the output end of the comparator is respectively connected with the single-chip microcomputer control module 107, the pulse width modulation module 108, the single-chip microcomputer control The module 107 is connected with the pulse width modulation module 108 , the pulse width modulation module 108 is connected with the high frequency driving module 109 , and the high frequency driving module 109 is connected with the high frequency inverter module 102 . The single-chip microcomputer control module is respectively connected with a high-frequency arc striking module 113 and a man-machine dialogue panel 114 . The safety protection circuit includes a network voltage detection module 105 and a voltage protection module 106; one end of the network voltage detection module 105 is connected to the three-phase AC power supply connected, and the other end is connected to the voltage protection module 106, and the voltage protection module 106 is connected to the pulse width respectively. The modulation module 108 and the single-chip microcomputer control module 107 are connected. The network voltage detection module 105 detects the three-phase AC input voltage, which is a commonly used voltage detection device. The voltage protection module 106 is a commonly used comparator to realize undervoltage and overvoltage protection. The comparator uses the commonly used TL084 comparator to compare the feedback current signal with the given current parameters. The current and voltage detection module 112 is a current and voltage sensor connected to the load. One end of the temperature detection module 110 is connected to the heat sink for temperature detection in the high-frequency inverter module 102, and the other end is connected to the overheat protection module 111, which is connected to the pulse width modulation module 108 to play the role of overheat protection .

As shown in Figure 2, in the main circuit, the three-phase AC input power supply is connected to the rectification filter module 101, and then connected to the filter links L1, C2, C2-A, C2-B, C3, C3-A, C3-B, C4, C5, then connect the high-frequency inverter module 102, the output is connected to the primary of the high-frequency power transformer T1 of the power transformation module 103, and the secondary of the transformer passes through the high-frequency full-wave rectification circuit D6A～D6B, and the filter links L2, C10, C11, C12, and R9 To output direct current, the above links constitute a power main circuit, and the high-frequency inverter module 102 includes two two-unit IGBTs VT ₁ -VT ₂ . Meanwhile, the current and voltage detection module 112 is a sensor connected to the output load terminal.

As shown in Figure 3, the pulse width modulation module 108 and the high frequency drive module 109 are mainly composed of the error amplifier circuit of the pulse width modulation module 108, the integrated control chip SG3525 and its peripheral circuits, and the drive module and auxiliary circuit of the high frequency drive module 109 connected to each other. The current feedback of the overcurrent protection is connected to the pin 2 of the integrated control chip SG3525 after comparison and amplification, and is used as the input signal of the integrated control chip SG2534. Comparing with the error signal inside the integrated control chip SG3525, the integrated control chip SG3525 outputs two corresponding PWM signals. The two complementary PWM signals are respectively used as driving signals for the switching tubes VT ₁ -VT ₂ of the inverter bridge. At the same time, the current and voltage detection module 112 is connected to the integrated control chip SG3525 of the pulse width modulation module 108 after comparing with the reference current and voltage signals.

As shown in FIG. 4 , the single-chip microcomputer control module 107 is mainly composed of a single-chip microcomputer PALCE22V10H, a logic circuit chip ULN2003A and auxiliary circuits connected to each other. The single-chip microcomputer PALCE22V10H system mainly realizes the functions of external monitoring and man-machine dialogue. External monitoring signals such as power supply indication, fault indication, air pressure indication, gas detection, etc. are all controlled by single-chip microcomputer PALCE22V10H, welding mode selection, pulse frequency during pulse welding, falling time, welding current, high-frequency arc ignition, digital ammeter The control of etc. also all is finished by the one-chip computer control module 107. Using the single-chip microcomputer control module 107 to control external monitoring and man-machine dialogue makes the multi-parameter control of the welding power source easy to control, making the use of the welding power source easier and easier to popularize. ULN2003A is connected with various protection circuits, such as undervoltage protection, overvoltage protection, and overheating protection, and then connected with single-chip microcomputer PALCE22V10H or pulse width modulation module 108 .

As shown in Figure 5, in the high-frequency arc ignition module, the IC1555 trigger controls the high-frequency switch FET to quickly turn on and off, so that the primary side of T1 generates high-frequency pulse signals, and through the transformer coupled with the load circuit, Make the output end get high-frequency signal. Under high pressure and high frequency, non-contact arc ignition can be realized.

As shown in Figure 6, in the high-frequency inverter module, in order to prevent the IGBT from being damaged by the instantaneous current and voltage impact when the IGBT is turned on and off, an RC absorption protection circuit is connected in parallel between the C and E poles of the IGBT.

As shown in Figure 7, in the rectification and filtering module, D1~D2 are fast diode groups for output rectification, and R5, C9, R11, and C17 respectively form the RC absorption circuits of the upper and lower symmetrical diode groups.

When the utility model is applied, the three-phase power-frequency alternating current passes through the rectifying and filtering module 101 and becomes a smooth direct current, and then enters the high-frequency inverter module 102, and the single-chip microcomputer control module 107 compares the current of the load detected by the current and voltage detection module 112 with the set value , through the control algorithm operation of the single-chip control module 107, an input signal is sent to the pulse-width modulation module 108, and the pulse-width modulation module 108 generates two PWM signals according to the algorithm set by the single-chip control module 107, and the two PWM signals are passed through the high-frequency The drive module 109 amplifies to control the switching on and off of the switching tube of the high-frequency inverter module 102, so as to obtain 20KHz high-frequency high-voltage power, which is then converted by the power transformer module 103 into a high-frequency high-voltage power that meets the welding process requirements. The pulse current with low current and voltage is then passed through the rectification and smoothing module 104 to obtain a smoother direct current, that is, the outer loop average value closed-loop control process. The temperature detection module 110 detects the temperature of the heat sink and sends it to the pulse width modulation module 108 to control the high-frequency inverter module 102 to form an overheating protection control to ensure the safe operation of the power supply; the network voltage detection module 105 detects the three-phase power frequency voltage, Send the detected voltage signal to the voltage protection module 106. If an overvoltage or undervoltage occurs, the voltage protection module 106 will send a control signal to the pulse width modulation module 108 to generate a low level and pass through the high frequency drive module 109. The switching tube of the high-frequency inverter module 102 is turned off to protect the safe operation of the main circuit.

As mentioned above, the utility model can be better realized.

Claims (4)

1, a kind of IGBT contravariant DC pulse argon arc welding power source, comprise cabinet and built-in circuit, it is characterized in that, described built-in circuit comprises main circuit, Current Feedback Control circuit, described main circuit comprises that rectification filtering module, high-frequency inversion module, power transformation module and the level and smooth module of rectification connect to form successively, the external three-phase alternating current input of described rectification filtering module power supply, the level and smooth module external load of described rectification; Described Current Feedback Control circuit comprises the current/voltage detection module, the given module of pulse parameter, comparator, single chip control module, pulse width modulation module and high-frequency drive module are formed, one end of described current/voltage detection module is connected with load, the other end is connected with the input of comparator, the given module of described pulse parameter is connected with another input of comparator, the output of described comparator respectively with single chip control module, pulse width modulation module is connected, described single chip control module is connected with pulse width modulation module, described pulse width modulation module is connected with the high-frequency drive module, and described high-frequency drive module is connected with the high-frequency inversion module; Described single chip control module is connected with high-frequency arc strike module and human-computer dialogue panel respectively.

2, a kind of IGBT contravariant DC pulse argon arc welding power source according to claim 1, it is characterized in that, described main circuit comprises safety protective circuit, and described safety protective circuit comprises net pressure detection module, voltage protection module, temperature detecting module, overtemperature protection module composition; Described net presses detection module one end to be connected with three-phase alternating-current supply, and the other end is connected with the voltage protection module, and described voltage protection module is connected with pulse width modulation module, single chip control module respectively; Described temperature detecting module one end is connected with the high-frequency inversion module, and the other end is connected with the overtemperature protection module, and the overtemperature protection module is connected with pulse width modulation module.

3, a kind of IGBT contravariant DC pulse argon arc welding power source according to claim 1 is characterized in that described single chip control module mainly is made up of single-chip microcomputer PALCE22V10H, logic circuit chip ULN2003A and peripheral circuit thereof.

4, a kind of IGBT contravariant DC pulse argon arc welding power source according to claim 1 is characterized in that described pulse width modulation module mainly is made up of error amplifying circuit, integrated control chip SG3525 and peripheral circuit thereof.

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