Double closed loop control strategy for plasma cutting inverter

作者：Liu Baoqi^*; Duan Shanxu; Li Xun; Zhao Geng; Liu Bangyin

来源：Proceedings of the CSEE, 2011, 31(9): 15-22.

• Air plasmas
• Arc ignition
• Arc ignition process
• Control methods
• Current characteristic
• Current-reference feedforward link
• Cutting load
• Cutting process
• Double closed loop
• Double closed loop control
• External currents
• Fast response
• Non-contact
• Output voltages
• Plasma cutting
• Reference feedforward
• Small overshoot

This paper proposed a double closed loop control strategy composed of inner voltage-loop and external current-loop with a current-reference feedforward link, which was based on the output voltage and current characteristics of the non-contact arc ignition and cutting process in an air plasma cutting inverter. An equivalent mathematical model of the cutting inverter was built up, then frequency domain analysis and designing work for the double closed loop controller was put up also. Simulations and experiments were given to verify that the proposed control method shows fast response, small overshoot, strong adaptation and high steady precision, which overcomes the drawbacks of potential failure when arc igniting in traditional control methods, and it increased the success rate of arc ignition significantly, and the restraining ability to disturbance of cutting load is enhanced obviously also. ? 2011 Chin. Soc. for Elec. Eng.

• 出版日期2011
• 单位华中科技大学