【作者】 雷冬雪；

【导师】 元哲石；

【作者基本信息】 吉林大学 ， 材料加工工程， 2008， 硕士

【摘要】 逆变切割技术是针对切割电弧负载特性和切割工艺要求,应用现代电力电子学理论和自动控制理论,实现电能的高效变换和控制的一门应用学科。其研究内容横跨焊接电弧物理、切割工艺学、功率电子和电磁器件、开关电路拓扑、逆变电源系统控制技术及其建模、分析和计算机仿真等各个领域。切割逆变电源现在正向着高效、节能、优质的小型化切割电源方向发展。本文对便携式小功率切割电源的研制进行了分析,并对其主电路、工作原理、控制电路及保护系统做了较详尽的介绍,比较成功地设计出一种小功率高可靠性的逆变切割电源。该电源采用MOSFET(设计开关频率为100kHz)逆变式全桥型主电路,控制系统部分采用了脉宽调制技术(PWM),PWM芯片为SG3525,MOSFET驱动电路采用脉冲变压器进行驱动,控制电路与主电路之间通过变压器进行隔离,提高了系统的可靠性和安全性。设计脉宽调制电路并对其原理进行分析,还设计了开关管缓冲电路、过流保护、过热保护及过压保护等具有保护功能的电路,同时设计了高频引弧电路及其程序控制电路。本文通过理论计算和实验分析证明切割电源的工作状态符合要求,该切割电源实现了小型化,具有比较稳定可靠的性能。更多还原

【Abstract】 With the development of modern industrial production and science technology, cutting technique progressed unremittingly. The high quality cutting work does not get away from the high-quality cutting equipments. The advanced technology and high-quality in the field of cutting are more and more reflected in the high-tech cutting equipment and modernization extent. The plasma cutting technique has a huge function in the production of industry. It can cut all black or non-ferrous, including various high melting point metals and the metals that other cutting methods can not cut, such as stainless, heat-resistant steel, cast iron, copper, aluminum and its alloys. When using non-transfer arc, the workpiece is not link power, under such circumstances, it can cut a variety of non-conductive materials, non-metallic materials such as refactory bricks, concrete and so on.The plasma arc use for cutting is different with the common welding arc. First, its electric arc is compressed. Secondly, the plasma arc use for cutting is longer. Along with the thickness of the cutting work piece increasing, the arc length is also increasing. The work voltage of cutting can be up to 100～200V. The non-load voltage of the cutting power supply can be up to 200～300V, for the stability of arc and igniting arc easily. In this paper, the work voltage of cutting is 95V, and the non-load voltage of the cutting power is up to 230V.With the development of the electric power electronics and the micro-electronics, the new devices, the advanced control technique and the constant introduction of new technology. The cutting technique gets the most advance by leaps and bounds of development. High speed, efficient, digital and the intelligent are the main development direction of the modern cutting technology. In recent years, with the continuous development of inverter technology, cutting inverter power becomes the development trend of cutting power. Inverter cutting machine with small size, light weight, energy saving, high performance control and dynamic response speed, which easily to control in the cutting process.Presently, three-phase cutting machine is very weight, not easy to carry, according to the needs of manufacturers, design the single-phase inverter air plasma cutting power. Detailed analysis the structure and principles about the inverter air plasma cutting power.Optimizate the reasonable layout and design, including the complete research tasks such as the main circuit, the control circuit, pulse width modulation circuit, driving circuit, high-frequency arc circuit, the protection circuit, the process control circuit and cutting power debugging.The inverter power frequency and load sustained rate are high, energy saving, low power consumption, small size, light weight,easy to carry, particularly suitable for outdoor mobile operations.In this paper, analyze the implementation of the program and integral part of the cutting power.This text carries on experiment analysis in the implement and project of power supply. Give the experiment records in the process of data and relate wave form. Carry on analytical research in the process of problems and put forward solution. The experiment results show that the inverter cutting machine main circuit has rapid response-speed, the control circuit is simple and reliable,continuous adjustable cutting current, accurate intuitive, built-in buffer, overhested,over-current, over-voltage protection circuit. The power compared with the flame cutting, use cheap compressed air to cut, low cost and high speed. Compared with the traditional cutting machine, the inverter power has high success rate arc, arc voltage, and energy concentration, cutting ability, and cutting speed, slotted narrow, smooth and small deformation. The design is meet concept and requirements.更多还原