The Half-bridge Inverter Welding Power System Modeling And Simulation Technology

The circuit of a half-bridge inverter welding power supply is designed. The modelof the main circuit is established. An analog double closed loop control system isdesigned, and the emulator result is given out.The hardware circuits include main circuit, IGBT driving circuit and protectingcircuit. The main circuit includes rectifier and filter circuit in input, half-bridge invertercircuit (including transformers), high frequency filter rectifier circuit in output, thesampling and isolation circuit of feedback voltage and current. The protecting circuitincludes over-voltage and under voltage protection circuit, soft start and PWMinterlocking circuit. On the base of this, we establish a small-signal model of thehalf-bridge circuit. On the base of small signal model, we design the analog currentcontroller and the analog voltage controller, and gives out designing steps. To develop ofdigital inverter welding power supply further, we discrete the analog control algorithm,and give digital algorithm to facilitate the realization of DSE Based on the performancerequirements of the arc welding, we determine the parameters of double closed-loopsystem of voltage and current. Finally, we simulate the model, draw the Porter figures ofthe compensation network under different parameters establish transfer function model inSimulink, give out the simulation results that verify the correctness of the theory.We also research the inverter welding power supply controlled by DSP elementarily.Using TMS320LF2407Amade by TI as the controlling chip, we give out the flowchart ofthe main program, PWM waves procedures and AD conversion, and the flowchart ofcontrol algorithm. All the work paves the way for the following research.