The Development Of Power Part In Medium-plasma Aqueous Digestion And Welding Machines

The medium-plasma aqueous digestion welding machines is a small cutting welding equipment of comprehensive function, energy-saving, environmental protection, and easy-to-carry. The focus of this thesis is the host of High Power Inverter part of the medium-plasma aqueous digestion and welding machines. The power part is not only the power output of the whole medium-plasma aqueous digestion and welding machines, but also the central control of the entire device. The host of the power can adjust the speed of water electrolysis to control the size and stability of the plasma flame.Host power includs three circuit boards which are the power board, control board, and power board. The main function of those circuit boards is the power supply, inverter circuit, mode control, and protection circuitry.The main function of power supply uses AC110～235V conversions of DC+5V,±12V and a high frequency oscillation source, and through a series of step of plastic, DC/DC, transformer and filter.The functions of the inverter circuit are power control and stable arc. The roles of the inverter circuit are high efficiency DC transformer and power control. The stable arc is very important when the medium-plasma aqueous digestion and welding machines are normally working. The machine through closed-loop phase control of the inverter circuit to adjust the power can make a stable plasma arc.The plasma arc of the medium-plasma aqueous digestion and welding machines has different states at Mode1and Mode2. The device can cut or weld different materials through the switching of the two modes. They all need control plasma arc in cutting or welding of different material in order to reach a certain depth of cut or welding process.The host power supply is very easy to cause overheating, overcurrent, or overvoltage because it usually work in high frequency, high current, and high voltage. These functions is accomplished by the protection circuit.This device has the features of advanced design, compact structure, stable performance. The test results prove that this power supply in full compliance with the plasma arc of the medium-plasma aqueous digestion and welding machines function requirements.