Intelligent multi-pulse capacitive energy storage welding machine circuit

Abstract

The utility model relates to the technical field of capacitive energy storage welding machines, and particularly discloses an intelligent multi-pulse capacitive energy storage welding machine circuit. Comprising a single-phase rectification unit used for stably rectifying electric energy and charging, an energy storage unit used for storing the electric energy, a voltage discharge unit used for controlling capacitor voltage, a protection unit used for preventing reverse voltage generated in a circuit from puncturing a capacitor in the energy storage unit, and a welding unit used for welding and welding discharge. Through cooperation of the single-phase rectification unit, the energy storage unit, the bleeder voltage unit, the protection unit and the welding unit, and no current-limiting resistor exists between the single-phase rectification unit and the energy storage unit, a current-limiting resistor and a single-phase rectification bridge circuit in a traditional circuit are omitted, the problem that an existing energy storage machine can only be charged and discharged at a time can be solved, and the reliability of the energy storage machine is improved. And continuous and rapid charging and discharging can be realized, the equipment is more power-saving and energy-saving, and the energy utilization efficiency is better.

Description

Technical Field

[0001] The utility model relates to the technical field of capacitor energy storage welding machines, in particular to an intelligent multi-pulse capacitor energy storage welding machine circuit. Background Art

[0002] Energy storage welding machine, also known as capacitive energy storage welding machine, mainly utilizes capacitor to store energy, then discharges the voltage on the capacitor instantaneously to weld the workpieces together. The welding time of energy storage welding machine is generally 3-50ms, and the welding time of capacitive energy storage welding machine cannot be adjusted. In the prior art, the control circuit used to control the charging and discharging of capacitor in energy storage welding machine has the following defects: First, a single charging thyristor is used to charge the capacitor in the charging and discharging circuit. Although the charging thyristor can basically meet the charging demand, the charging efficiency is slow and it is not easy to accurately control the charging voltage; second, there is no multiple charging and discharging technology using thyristor rectification scheme in the existing scheme, and the charging current is not easy to control in the original scheme.

[0003] In view of the above defects, we need to propose an intelligent multi-pulse capacitive energy storage welding machine circuit and control method to solve the above problems, so that it can charge and discharge continuously and quickly and can accurately control the voltage, the equipment is more energy-saving and the energy utilization efficiency is better. Utility Model Content

[0004] The purpose of the utility model is to provide an intelligent multi-pulse capacitive energy storage welding machine circuit, which greatly improves its charging speed, greatly improves the energy utilization power, makes the equipment more power-saving, and improves the energy utilization efficiency, so as to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an intelligent multi-pulse capacitive energy storage welding machine circuit, including a single-phase rectifier unit for stably rectifying electric energy and charging, a capacitive energy storage unit for storing electric energy, a discharge voltage unit for controlling the capacitor voltage, a protection unit for preventing reverse voltage from being generated in the circuit from breaking down the capacitor in the energy storage unit, and a welding unit for welding and welding discharge, the single-phase rectifier unit is externally connected to a single-phase AC voltage of 220V-800V, and the single-phase rectifier unit forms a loop with the energy storage unit after receiving the single-phase AC voltage, the energy storage unit, the discharge voltage unit and the protection unit are sequentially connected in parallel to form a closed-loop system, and the energy storage unit is connected in parallel with the welding unit.

[0006] Preferably, the single-phase rectifier unit includes thyristors SRC1 and SRC3 connected in series and thyristors SRC2 and SRC4 connected in series, and the thyristor SRC1 is connected to the thyristor SRC2, and the thyristor SRC3 is connected to the thyristor SRC4, and input pins for effectively accessing the single-phase AC voltage are provided between the thyristors SRC1 and SRC3 and between the thyristors SRC2 and SRC4, and the thyristors SRC1, SRC3, SRC2 and SRC4 are connected to each other in the form of a rectifier bridge using two thyristor modules.

[0007] Preferably, the single-phase rectifier unit also includes a synchronization signal detection unit for detecting a trigger signal, the synchronization signal detection unit is connected to an MCU or FPGA for outputting a trigger signal, and the MCU or FPGA is connected to a synchronization signal pin of the single-phase rectifier unit.

[0008] Preferably, the energy storage unit is composed of a plurality of first capacitors connected in parallel, and two ends of the first capacitors are respectively connected to the K pole of the thyristor SRC2 and the A pole of the thyristor SRC4.

[0009] Preferably, the discharge voltage unit includes an insulated gate bipolar transistor IGBT1 and a resistor R1, the C pole of the insulated gate bipolar transistor IGBT1 is connected to the connection end of the first capacitor and the thyristor SRC2 close to the single-phase rectifier unit, the E pole of the insulated gate bipolar transistor IGBT1 is connected to one end of the resistor R1, and the other end of the resistor R1 is connected to the connection end of the first capacitor and the protection unit close to the protection unit.

[0010] Preferably, the protection unit is composed of a resistor R2 and a reverse freewheeling diode D1 connected in series, and the non-connected end of the resistor R2 and the non-connected end of the reverse freewheeling diode D1 are respectively connected to two ends of the first capacitor.

[0011] Preferably, the welding unit includes a welding transformer T1, a thyristor SRC5 and a thyristor SRC7, one end of the transformer T1 is connected to the A pole of the thyristor SRC5 and the K pole of the thyristor SRC7, the other end of the transformer T1 is connected in parallel with the thyristor SRC6 and the thyristor SRC8, and the K pole of the thyristor SRC5 is respectively connected to the K pole of the thyristor SRC6 and the non-connected end of the reverse freewheeling diode D1, and the A pole of the thyristor SRC7 is respectively connected to the A pole of the thyristor SRC8 and the non-connected end of the resistor R2.

[0012] Compared with the prior art, the beneficial effects of the utility model are:

[0013] 1. The utility model has the characteristics of high efficiency, low energy consumption, environmental protection and safety through the coordination of a single-phase rectifier unit, an energy storage unit, a discharge voltage unit, a protection unit and a welding unit. There is no current limiting resistor between the single-phase rectifier unit and the energy storage unit, and the current limiting resistor and the single-phase thyristor rectifier bridge circuit in the traditional circuit are eliminated. The utility model can solve the problem that the existing energy storage machine can only be charged and discharged once, so that it can be charged and discharged continuously and quickly, and the equipment is more energy-saving and energy-saving, and the energy utilization efficiency is better.

[0014] 2. The utility model cooperates with the protection unit and the welding unit. When a reverse current passes through, the protection unit protects the energy storage unit to prevent the reverse voltage from damaging the capacitor in the energy storage unit, thereby increasing the service life of the energy storage unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a system block diagram of the utility model;

[0016] Figure 2 This is a circuit diagram of the utility model. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] See also Figure 1-2The utility model provides a technical solution: an intelligent multi-pulse capacitive energy storage welding machine circuit, including a single-phase rectifier unit for stably rectifying electric energy and with charging, a capacitive energy storage unit for storing electric energy, a discharge voltage unit for controlling the capacitor voltage, a protection unit for preventing the reverse voltage generated in the circuit from breaking down the capacitor in the energy storage unit, and a welding unit for welding welding discharge. The single-phase rectifier unit is externally connected to a single-phase AC voltage of 220V-800V. After receiving the single-phase AC voltage, the single-phase rectifier unit forms a loop with the energy storage unit. The energy storage unit, the discharge voltage unit and the protection unit are sequentially connected in parallel to form a closed-loop system. The energy storage unit is connected in parallel with the welding unit. The coordination of the single-phase rectifier unit, the energy storage unit, the discharge voltage unit, the protection unit and the welding unit has the characteristics of high efficiency, low energy consumption, environmental protection and safety, and there is no current limiting resistor between the single-phase rectifier unit and the energy storage unit, which cancels the current limiting resistor and the single-phase thyristor rectifier bridge circuit in the traditional circuit, which saves more energy consumption, and solves the problem that the existing energy storage machine can only be charged and discharged once, so that it can be charged and discharged continuously and quickly, and the equipment is more energy-saving and energy-saving, and the energy utilization efficiency is better. Because this solution improves the energy utilization efficiency, it does not need wind energy and water cooling. The traditional circuit consumes more energy and has serious heat generation and requires air cooling and water cooling, which is more advantageous than the traditional circuit;

[0019] The single-phase rectifier unit includes thyristors SRC1 and SRC3 in series and thyristors SRC2 and SRC4 arranged in series, and the thyristor SRC1 is connected to the thyristor SRC2, and the thyristor SRC3 is connected to the thyristor SRC4. Input pins for effectively accessing the single-phase AC voltage are arranged between the thyristors SRC1 and SRC3 and between the thyristors SRC2 and SRC4. The thyristors SRC1, SRC3, SRC2 and SRC4 are connected to each other in the form of a rectifier bridge using two thyristor modules. The circuit is controlled to be rectified by controlling the conduction of the thyristor SRC1 and SRC4 or the conduction of the thyristor SRC2 and SRC3. When the output DC voltage needs to be adjusted, it can be achieved by changing the trigger angle of the SCR.

[0020] The single-phase rectifier unit also includes a synchronization signal detection unit for detecting a trigger signal. The synchronization signal detection unit is connected to an MCU or FPGA for outputting a trigger signal. The MCU or FPGA is connected to the synchronization signal pin of the single-phase rectifier unit. When the input is a single-phase positive half-wave, the synchronization signal unit detects the MCU or FPGA, and the MCU or FPGA outputs a synchronization trigger signal to trigger the positive half-wave conduction of thyristors SRC1 and SRC4. When the input is a single-phase negative half-wave, the synchronization signal unit detects the MCU or FPGA, and the MCU or FPGA outputs a synchronization trigger signal to trigger the negative half-wave conduction of thyristors SRC2 and SRC3. After the single-phase thyristor rectifier bridge rectifies and the half-wave after the energy storage unit is sorted, the energy storage unit has a stable voltage.

[0021] The synchronization signal detection unit includes an amplifier chip for zero-crossing signal detection and synchronization signal detection. The amplifier chip is set to be a LM358 chip. Due to its high speed and high gain characteristics, the LM358 chip is very suitable for realizing various synchronization detection functions. When performing synchronization signal detection, the LM358 chip can perform necessary amplification and shaping on the input synchronization signal to ensure the accuracy and stability of the signal.

[0022] The energy storage unit is composed of a plurality of first capacitors connected in parallel (such as Figure 2 The capacitors C1, C2, C3 and C4 are marked in the figure. The two ends of the first capacitor are connected to the K pole of the thyristor SRC2 and the A pole of the thyristor SRC4 respectively. The first capacitors are connected in parallel to provide sufficient capacitor energy storage capacity to meet the circuit's demand for energy storage and ensure stability and reliability during the welding process. The energy storage unit has no voltage when not in use. When maintenance is required or workers accidentally touch the energy storage unit, no one will be injured. The traditional energy storage unit stores electrical energy through batteries. Since the battery also has voltage when not in use, it will hurt people when it is repaired or accidentally touched.

[0023] The discharge voltage unit includes an insulated gate bipolar transistor IGBT1 and a resistor R1, one end of the insulated gate bipolar transistor IGBT1 is connected to the connection end of the first capacitor and the thyristor SRC2 close to the single-phase rectifier unit, the other end of the insulated gate bipolar transistor IGBT1 is connected to one end of the resistor R1, and the other end of the resistor R1 is connected to the connection end of the first capacitor and the protection unit close to the protection unit. When the voltage of the energy storage unit is too high, the voltage is reduced by turning on the insulated gate bipolar transistor IGBT1 to keep the system voltage accurate, wherein the insulated gate bipolar transistor combines the characteristics of MOSFET (metal-oxide-semiconductor field effect transistor) and BJT (bipolar transistor), has a lower on-resistance and a higher switching speed, thereby achieving high efficiency while reducing energy loss. Specifically, the IGBT opens or closes the current channel by controlling the voltage of its gate terminal. When the positive input voltage passes through the gate, the emitter keeps the drive circuit open; and when the gate voltage is zero or slightly negative, the circuit is closed, achieving efficient voltage control and reduction.

[0024] The protection unit is composed of a resistor R2 and a reverse freewheeling diode D1 connected in series. The non-connected end of the resistor R2 and the non-connected end of the reverse freewheeling diode D1 are respectively connected to the two ends of the first capacitor. When a reverse current passes through the welding unit, the energy storage unit is protected by the protection unit to prevent the reverse voltage from damaging the capacitor in the energy storage unit, thereby increasing the service life of the energy storage unit.

[0025] The welding unit includes a welding transformer T1, a thyristor SRC5 and a thyristor SRC7, one end of the transformer T1 is connected to the A pole of the thyristor SRC5 and the K pole of the thyristor SRC7, the other end of the transformer T1 is connected in parallel with the thyristor SRC6 and the thyristor SRC8, and the K pole of the thyristor SRC5 is respectively connected to the K pole of the thyristor SRC6 and the non-connected end of the reverse freewheeling diode D1, the A pole of the thyristor SRC7 is respectively connected to the A pole of the thyristor SRC8 and the non-connected end of the resistor R2, the thyristor SRC5, the thyristor SRC6, the thyristor SRC7 and the thyristor SRC8 form a thyristor rectifier bridge circuit, and the circuit control of charging and discharging back and forth is performed by respectively turning on the thyristor SRC5 and the thyristor SRC8 and turning on the thyristor SRC6 and the thyristor SRC7, so that the transformer T1 can provide electrical energy support for the welding operation.

[0026] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An intelligent multi-pulse capacitor energy storage welding machine circuit, characterized in that: It includes a single-phase rectifier unit for stably rectifying electric energy and charging, a capacitive energy storage unit for storing electric energy, a discharge voltage unit for controlling the capacitor voltage, a protection unit for preventing reverse voltage from being generated in the circuit and breaking down the capacitor in the energy storage unit, and a welding unit for welding and discharging. The single-phase rectifier unit is externally connected to a single-phase AC voltage of 220V-800V. After receiving the single-phase AC voltage, the single-phase rectifier unit forms a loop with the energy storage unit. The energy storage unit, the discharge voltage unit and the protection unit are connected in parallel in sequence to form a closed-loop system, and the energy storage unit is connected in parallel with the welding unit.

2. The intelligent multi-pulse capacitive energy storage welding machine circuit according to claim 1 is characterized in that: The single-phase rectifier unit includes a thyristor SRC1 and a thyristor SRC3 connected in series, and a thyristor SRC2 and a thyristor SRC4 connected in series, and the thyristor SRC1 is connected to the thyristor SRC2, and the thyristor SRC3 is connected to the thyristor SRC4. Input pins for effectively accessing a single-phase AC voltage are provided between the thyristor SRC1 and the thyristor SRC3, and between the thyristor SRC2 and the thyristor SRC4. The thyristor SRC1, the thyristor SRC3, the thyristor SRC2 and the thyristor SRC4 are connected to each other in the form of a rectifier bridge using two thyristor modules.

3. The intelligent multi-pulse capacitive energy storage welding machine circuit according to claim 2 is characterized in that: The single-phase rectifier unit also includes a synchronization signal detection unit for detecting a trigger signal, the synchronization signal detection unit is connected to an MCU or FPGA for outputting a trigger signal, and the MCU or FPGA is connected to a synchronization signal pin of the single-phase rectifier unit.

4. The intelligent multi-pulse capacitive energy storage welding machine circuit according to claim 3 is characterized in that: The energy storage unit is composed of a plurality of first capacitors connected in parallel, and two ends of the first capacitors are respectively connected to the K pole of the thyristor SRC2 and the A pole of the thyristor SRC4.

5. The intelligent multi-pulse capacitive energy storage welding machine circuit according to claim 4 is characterized in that: The discharge voltage unit includes an insulated gate bipolar transistor IGBT1 and a resistor R1, wherein the C pole of the insulated gate bipolar transistor IGBT1 is connected to the connection end of the first capacitor and the thyristor SRC2 close to the single-phase rectifier unit, the E pole of the insulated gate bipolar transistor IGBT1 is connected to one end of the resistor R1, and the other end of the resistor R1 is connected to the connection end of the first capacitor and the protection unit close to the protection unit.

6. The intelligent multi-pulse capacitive energy storage welding machine circuit according to claim 5 is characterized in that: The protection unit is composed of a resistor R2 and a reverse freewheeling diode D1 connected in series, and the non-connected end of the resistor R2 and the non-connected end of the reverse freewheeling diode D1 are respectively connected to the two ends of the first capacitor.

7. The intelligent multi-pulse capacitive energy storage welding machine circuit according to claim 6 is characterized in that: The welding unit includes a welding transformer T1, a thyristor SRC5 and a thyristor SRC7, one end of the transformer T1 is connected to the A pole of the thyristor SRC5 and the K pole of the thyristor SRC7, the other end of the transformer T1 is connected in parallel with the thyristor SRC6 and the thyristor SRC8, and the K pole of the thyristor SRC5 is respectively connected to the K pole of the thyristor SRC6 and the non-connected end of the reverse freewheeling diode D1, and the A pole of the thyristor SRC7 is respectively connected to the A pole of the thyristor SRC8 and the non-connected end of the resistor R2.

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