【摘要】 基于逆变式空气等离子切割电源非接触式引弧及切割过程对输出电压电流的控制要求,提出一种具有指令电流前馈的电流外环电压内环的双闭环控制策略,通过建立切割电源的等效数学模型,对双闭环控制系统进行了频域分析与设计。仿真和实验表明:所提控制方法具有响应速度快、超调小、负载适应性强和稳态精度高等优点,克服了传统控制方式下可能出现引弧失败的缺点,极大地提高了切割起弧成功率,并且对切割负载的扰动有很强的抑制能力。更多还原

【Abstract】 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.更多还原