Study On Fully Digital High Power Square Wave Welding Power Source Based On ARM Cortex-M3

With the development of domestic economy, the increasingly prominent problem of environment, energy and resources utilization put new requirements to green technology. The green metal materials provide the material basis for the future development of green technology, especially in some special departments such as:aviation, aerospace and nuclear power and so on, aluminum, magnesium and their alloy material are widely used. High power welding inverter power supply solved the problem because of their physical properties and metallurgical characteristics determine the performance of poor welding, is a kind of ideal green metal welding power.In the paper, using the Cortex-M3kernel ARM controller as the master chip designs a full digital high-power square wave welding power supply, which has the DC. DC pulse and square wave three welding modes. The square wave mode is mainly used to weld aluminum magnesium and other green metal materials, and join the DC and DC pulse welding modes, meet a variety of material of welding process requirements. The main research work includes hardware design of the main circuit for high-power square wave power, hardware and software design of the control system, and experiment and waveform analysis.Firstly, the preface focuses on introducing the works on this topic research meaning, present study and trends. Secondly, this paper analyzes the full bridge topology, half bridge topological structure of the working principle, bases on the design parameters of the topic request, chooses the first inverter used full bridge topology; the second inverter used half bridge topology as the main circuit topology, and designs parameters of the main circuit’s key devices in detailed. And then, according to performance requirements of the digital control of microprocessor, this paper chooses the Cortex-M3kernel ARM chips as control core, in view of the main circuit control design hardware and software of main control board, and designs the digital panel for digital parameters. Finally, bases on this, the paper develops a20kW square wave welding power supply, and makes the actual welding experiments of the square wave welding power prototype, DC and DC pulsed welding experiments and square-wave welding experiments, acquisitions the ideal of output waveforms and satisfy the welding process requirements to validate the validity and feasibility of the scheme.