A digital controlled alternating electromagnetic stirring generator based on dual inverter structure  

作　　者：张芩 谢芳祥 朱磊 叶惠 王振民 

机构地区：[1]South China University of Technology, Guangzhou, 510640.

出　　处：《China Welding》2015年第4期74-80,共7页中国焊接（英文版）

基　　金：This investigation is supported by National Natural Science Foundation of China （No. 51375173 ） and Guangdong Provincial Science and Technology Project （ No. 2013B010402007, No. 2013B011302006, No. 2014B010104002）. （South China University of Technology, Guangzhou, 510640. ）

摘　　要：A digital controlled alternating electromagnetic stirring generator is proposed in this paper. The main circuit of the generator makes use of dual inverter structure among which the former inverter uses full bridge zero voltage switching topology and the latter inverter uses full bridge inverter circuit. To improve the dynamic response performance, the inverting frequency of the former inverter is as high us 100 kHz. The Cortex-M3 kernel based ARM microcontroller LM3S818 is adopted as the cybernetics core of the digital control system to achieve accurate, stable and flexible control of the generator. All the PWM signals for the former and latter inverters are generated by the LM3S818 directly. The constant current characteristic of the former inverter is obtained through current close-loop feedback control, and can ensure the operation safety when the output current waveform is at zero crossing point. Both simulation and experiment results show that the proposed generator is with such advantages as wide soft-switching range, perfect control accuracy and flexible waveform modulation, and can fulfill the requirements of electromagnetic stirring process.A digital controlled alternating electromagnetic stirring generator is proposed in this paper. The main circuit of the generator makes use of dual inverter structure among which the former inverter uses full bridge zero voltage switching topology and the latter inverter uses full bridge inverter circuit. To improve the dynamic response performance, the inverting frequency of the former inverter is as high us 100 kHz. The Cortex-M3 kernel based ARM microcontroller LM3S818 is adopted as the cybernetics core of the digital control system to achieve accurate, stable and flexible control of the generator. All the PWM signals for the former and latter inverters are generated by the LM3S818 directly. The constant current characteristic of the former inverter is obtained through current close-loop feedback control, and can ensure the operation safety when the output current waveform is at zero crossing point. Both simulation and experiment results show that the proposed generator is with such advantages as wide soft-switching range, perfect control accuracy and flexible waveform modulation, and can fulfill the requirements of electromagnetic stirring process.

关 键 词：electromagnetic stirring generator dual inverter digital control SOFT-SWITCHING ARM 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置] TG434.1[自动化与计算机技术—控制科学与工程]