A digital arc welding power supply was designed with the advanced reduced instruction set computer machine （ARM） and embedded real-time multi-task operating system micro C/OS- Ⅱ. The ARM, with its powerful calculat...A digital arc welding power supply was designed with the advanced reduced instruction set computer machine （ARM） and embedded real-time multi-task operating system micro C/OS- Ⅱ. The ARM, with its powerful calculating speed and complete peripheral equipments, is very suitable to work as the controller of the digital power supply. The micro C/OS- Ⅱ transplanted in ARM, helps to improve the respondent speed against various welding signals, as well as the reliability of the controlling software. The welding process consists of nine tasks. The tasks of great significance on reliability of the welder, for example, the A/D conversion of current and voltage, enjoy top priority. To avoid simultaneous-sharing on A/D converter and LCD module, two semaphores are introduced in to ensure the smooth performance of the welding power supply. Proven by experiments ,the ARM and the micro C/OS- Ⅱ can greatly improve both the respondent speed and the reliability of the digital welder.展开更多
The full-bridge zero-voltage and zero-current switching inverter, which can adjust the output power by keeping the duty-cycle of lagging arm constant, changing the duty-cycle of leading arm, is a common circuit topolo...The full-bridge zero-voltage and zero-current switching inverter, which can adjust the output power by keeping the duty-cycle of lagging arm constant, changing the duty-cycle of leading arm, is a common circuit topology of soft-switching inverter arc welding power supplies. However, the output power still remains a certain value when the duty-cycle of leading arm decreases to zero. The working-mode of soft-switching inverter and the waveforms of major parameters with the condition of duty-cycle of leading arm being zero are studied in this paper. U-1 characteristic experiments prove that the minimum output power of soft-switching circuit, which depends on the charged voltage of capacitors in parallel with leading arm, can be decreased by reducing the duty-cycle of lagging arm. By switching working-modes between half-bridge and full-bridge, the output power can swing from zero to the power rating.展开更多
设计了一套高频熔化极气体保护焊接设备。主电路主要由两套并联的电路组成,通过PIC单片机控制两支开关管导通与关断来切换高频脉冲电流,通过程序控制电源输出电流的大小。设计了一套有源缓冲电路用于吸收主电路开关管两端的尖峰电压,既...设计了一套高频熔化极气体保护焊接设备。主电路主要由两套并联的电路组成,通过PIC单片机控制两支开关管导通与关断来切换高频脉冲电流,通过程序控制电源输出电流的大小。设计了一套有源缓冲电路用于吸收主电路开关管两端的尖峰电压,既保证主电路安全工作的同时,又把开关管两端的尖峰能量反馈至主电路重复利用。经测试,设计的高频焊接设备峰值电流I_p可调节至150 A,基值电流I_b可调节至360 A,电流频率可调节范围为5~20 k Hz,脉冲电流可达到很快的上升及下降速度。采用此设备进行了Q235碳素结构钢的焊接工艺试验,焊缝成形良好。展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 50575074by the Scientific and TechnologicalProject of Guangdong Province, China, under Grant No 2003A1040310
文摘A digital arc welding power supply was designed with the advanced reduced instruction set computer machine （ARM） and embedded real-time multi-task operating system micro C/OS- Ⅱ. The ARM, with its powerful calculating speed and complete peripheral equipments, is very suitable to work as the controller of the digital power supply. The micro C/OS- Ⅱ transplanted in ARM, helps to improve the respondent speed against various welding signals, as well as the reliability of the controlling software. The welding process consists of nine tasks. The tasks of great significance on reliability of the welder, for example, the A/D conversion of current and voltage, enjoy top priority. To avoid simultaneous-sharing on A/D converter and LCD module, two semaphores are introduced in to ensure the smooth performance of the welding power supply. Proven by experiments ,the ARM and the micro C/OS- Ⅱ can greatly improve both the respondent speed and the reliability of the digital welder.
文摘The full-bridge zero-voltage and zero-current switching inverter, which can adjust the output power by keeping the duty-cycle of lagging arm constant, changing the duty-cycle of leading arm, is a common circuit topology of soft-switching inverter arc welding power supplies. However, the output power still remains a certain value when the duty-cycle of leading arm decreases to zero. The working-mode of soft-switching inverter and the waveforms of major parameters with the condition of duty-cycle of leading arm being zero are studied in this paper. U-1 characteristic experiments prove that the minimum output power of soft-switching circuit, which depends on the charged voltage of capacitors in parallel with leading arm, can be decreased by reducing the duty-cycle of lagging arm. By switching working-modes between half-bridge and full-bridge, the output power can swing from zero to the power rating.
文摘设计了一套高频熔化极气体保护焊接设备。主电路主要由两套并联的电路组成,通过PIC单片机控制两支开关管导通与关断来切换高频脉冲电流,通过程序控制电源输出电流的大小。设计了一套有源缓冲电路用于吸收主电路开关管两端的尖峰电压,既保证主电路安全工作的同时,又把开关管两端的尖峰能量反馈至主电路重复利用。经测试,设计的高频焊接设备峰值电流I_p可调节至150 A,基值电流I_b可调节至360 A,电流频率可调节范围为5~20 k Hz,脉冲电流可达到很快的上升及下降速度。采用此设备进行了Q235碳素结构钢的焊接工艺试验,焊缝成形良好。
