CO_2弧焊电源主电路中RC缓冲电路设计  

Design of RC snubber for main circuit of CO_2 arc welding power source

作　　者：朱学来[1] 黄文新[2] 

机构地区：[1]盐城工学院电气工程学院,江苏盐城224051 [2]南京航空航天大学自动化学院,江苏南京210016

出　　处：《电力自动化设备》2009年第11期140-143,共4页Electric Power Automation Equipment

摘　　要：全桥逆变CO2弧焊电源主电路IGBT开关动作时,在续流回路中由于负载的巨大变化及变压器的电感作用而形成电流、电压冲击,造成IGBT工作的不稳定。根据弧焊电源的工作原理设计了电弧负载仿真模块,建立了弧焊逆变主电路仿真模型,动态地仿真了焊接过程中负载频繁突变的特点。通过仿真分析得知,在续流过程中IGBT能够理想关断轨迹的条件是续流二极管不开通。根据具体的主电路参数和电路工作的续流初始时刻以及IGBT开通时,缓冲电容放电对参数的影响,计算出合理开关轨迹下RC缓冲电路中的电阻值,根据缓冲回路电阻的功率限制和开关轨迹的要求计算缓冲电容值。试验证明了弧焊逆变主电路仿真模型的正确性、IGBT理想关断轨迹条件的合理性及RC参数设计公式的正确性。When the IGBT of full-bridge inverter for CO2 arc welding power source switches,the current and voltage impact caused by the tremendous load ehange and transformer inductance on its stable operation of the after- flow circuit. The simulative module of arc load and the simulation model of arc welding inverter are established according to its working principle and the characteristics of frequent load sudden change during welding are dynamically simulated. Simulation results show that,the after-flow diode keeps closed is the condition of ideal IGBT turn- off track during after-flow. The resistor of RC buffer is set according to the parameters of main circuit,the initial time of after- flow and the influence of buffer capacitor discharge on the parameters when IGBT is open,while the capacitor of RC buffer is set according to the power limitation of resistor and the requirement of switching track. The correctness of arc welding inverter model, condition of ideal IGBT turn- off track and parameter setting formulas of RC buffer are proved by experiments.

关 键 词：弧焊电源 电压浪涌 RC缓冲电路 关断轨迹 电弧负载 

分 类 号：TM13[电气工程—电工理论与新技术]