新颖方波交流TIG电源二次逆变主回路的研究

Study on a Novel Second Inverting Main Circuit of the Square-wave AC TIG Inverter

为了提高方波交流双逆变电源的整机效率 ,降低成本 ,提出了一种半桥式二次逆变电路拓扑 ,它采用了耦合电感及恒压吸收电路 ,既提供了换流回路 ,又保证了交流电流过零的快速性。分析了其工作原理 ,并给出相关计算。实验表明该电路设计合理可靠 ,在较小输出电流情况下无需特殊稳弧装置便可获得满足焊接工艺要求的稳定电弧。

In order to improve the efficiency and reduce the cost of the square wave AC TIG machine, a novel topology of half bridge circuit is presented, which is composed of coupling reactor and snubbed circuit with constant voltage. Not only can it convert current but also make the AC current easily across zero. The principle of the main inverting stage of the machine is analyzed and the calculations of the correlative parameters are presented in this paper. Experiment shows that the design of the main circuit is rational and reliable. Without any other special devices, the pulse of stable arc created by the circuit structure itself can fit the need of the AC TIG welding.