CO2 gas shielded welding power sources are classified according to their external characteristics into steep-drop characteristic rectifier power sources, flat characteristic rectifier power sources, and multi-characteristic rectifier power sources. They can also be classified according to the method of adjusting the external characteristics into transformer primary and secondary side tap-changing type, magnetic amplifier type, thyristor type, and transistor type, etc.
The main circuit of an analog welding machine consists of a power frequency transformer, a three-phase rectifier bridge, and a transistor array. The advantage of this type of welding machine is its fast response speed, but the disadvantage is the high energy consumption of the transistor array. Therefore, it has been largely replaced by other types of power sources.
As a product of the combination of digital signal processing technology and arc welding process, the main control circuit of a digital welding machine has been directly replaced by digital technology, replacing the traditional analog technology. Digital welding machines have excellent system flexibility, better stability, higher control precision, and good interface compatibility. However, the implementation of a digital welding machine system is challenging; slow processing speed and poor anti-interference ability are the main disadvantages of digital control. The development of welding machines towards digitalization includes both the digitalization of the main circuit and the digitalization of the control circuit.
In recent years, high-power power electronic devices such as IGBTs have gained popularity among manufacturers due to their unique advantages and are gradually being applied in modern arc welding inverter power supplies. Technological innovation will become a key factor driving market development; for example, digital welding power supplies will be a future trend. With the deep integration of digital and intelligent technologies, medium-frequency three-phase welding power supply technology is developing towards intelligence. Looking to the future, it will be deeply integrated into the Industrial Internet, leveraging technologies such as cloud computing and big data analysis to achieve real-time online intelligent welding quality control.
