The Permanent Passive Welder Inverter Power Control Circuit Developed

In the industrial process, the welding technology is essential. Welding is applied not only in indoors or the place closed to the power source but also in the place without power source in modern social construction such as pipeline laying, railway and highway construction, power tower and communications tower construction, high-speed rail rapid repair and rescue and relief after geological disasters. This kind welding is permanent magnet intermediate frequency passive welding with own generator. The biggest advantage of the welding is small size, light weight and easy to move for the field work. But this kind welding only supplies alternating current frequency range of 500Hz to 600Hz, and so it is not supplied for the equipment such as mud pump, grinder and hand drill supplied by the frequency power in the construction site. Many users have a request the welding machine is equipped with 500Hz 220V frequency power to facilitate construction. Based on this request, by the commission of a welding machine manufacturer, we develop the 50Hz 220V frequency power inverter supporting the permanent magnet intermediate frequency passive welding. This paper summarizes the design process of the inverter.This paper summarizes the subject background and technical status. In addition, it briefly discuses the basic theory related to the project. Based on that, according to technical requirement of the mission statement, this paper discuses the design in detail included every part operation principle of the circuit system, design features and Methods in installation and debugging. This has two innovations. The one is applying the way of large-capacity and high-inductance inductive smoothing the output voltage to solve the problem which is when the pulse width changes square wave changes sensitively too. The other is designing the system structure with the overall balance and co-ordination approach to solve many problems in the condition of permanent magnet intermediate frequency passive welding without excitation adjustment mechanism. The problem includes stabilizing the output voltage, system protection, anti-electromagnetic interference, reducing the costs and stabilizing the system against strong motion.We achieve four aspects of the design. Firstly, we constitute the pulse circuit using SG3525 PWM control chip; secondly, we achieve the required protection for the circuit system through the use of a comparator and SG3525 pulse blocking feature; thirdly, we apply a large-capacity and high-inductance inductive smooth the output voltage to get feedback signal and apply the way of certain adjustment to stabilize the output voltage; finally, we produce a transformer to solve the issue of non-standard device which is difficult to get. After achieving the design, we have the prototype developed in strict commissioning, operation and assessment to realize the requirements and complete the task.