Research on two-channel interleaved two-stage paralleled Buck DC-DC Converter for plasma cutting power supply

As for high power plasma power supply, due to high efficiency and flexibility, multi-channel interleaved multi-stage paralleled Buck DC-DC Converter becomes the first choice. In the paper, two-channel interleaved two- stage paralleled Buck DC-DC Converter powered by three-phase AC power supply is selected as research subject, dedicated for the use of plasma cutting machine of 2×45kW, and the passivity-based control over the converter is analyzed theoretically at first, then simulated by means of MATLAB/SIMULINK, finally implemented on the modular product prototype. From the obtained results, it can be concluded that the passivity-based controller can be easily designed and implemented, which brings about the global stability and reluctance to outer perturbation, system parameter variation and load fluctuation, which also brings about better current sharing due to fast respond to the variations and the use of phase-shift driving technology and current sharing technology.