逆变弧焊电源的三相功率因数校正器

对于三相输入的大功率逆变弧焊电源,采用三相升压拓扑进行功率因数校正,以矢量变换的思想研究其调制过程.总体系统的控制采用了双环思想,内环为电流环,用以实现输入电流对电压的相位跟踪,外环为电压环,负责控制输出电压的恒定,并为电流内环提供调制指令,系统采用双环控制,为使系统实现单个开关周期校正控制误差的无差拍控制,整个系统通过TMS320LF2407A DSP芯片控制,采用saber软件进行了仿真辅助分析,给出了电路系统的结构框图和控制方案以及软件流程,实现了电源系统的数字化.试验结果实现了功率因数为1,三相输入电流与输入电压均同相,且为较为标准的正弦波,电流谐波畸变远小于10%的目的,满足了国际上关于谐波限制的标准.

A PFC stage of three-phase inverter welding power supply

For three phase large welding inverter power supply,three-phase boost topology is introduced as the power factor correction scheme. It's modulation process is analyzed using vector transformation method.We apply two-loop idea in the whole control system.The inner loop is current loop,and it is used to achieve that the input current is in phase with the input voltage using steady-stage deadbeat control to achieve the best dynamic performance.The outer loop is voltage loop,which control the output voltage to be a constant value and offer instruction for the inner current loop.In order to realize the deadbeat-control that can correct the control error in one switch period,TMS320LF2407A DSP is introduced to the control system,and saber software is used for simulation analyses,and the circuit system and software flow chart is put forward.We realize the digitalation of the control system.The experiment result is analyzed.Power factor by experiment is unit.Three phase input current are in phase with input voltage,and they are relative standard sine wave.The total harmonic distortion of the current is less than 10%,and all of this has meet the international harmonic criterrion.