【作者】 韩育强；

【导师】 赵侠；

【作者基本信息】 华中科技大学 ， 物理电子学， 2005， 硕士

【摘要】 高功率轴快流CO₂激光器越来越广泛地用于工业加工中。近年来出现的高频开关电源技术和以可编程芯片为核心的控制技术也逐渐在激光器设计中得到应用。现在的激光开关电源的发展趋势是数字化、智能化、高频化和模块化,因此,本课题选择以单片机为核心研制出一套高功率轴快流CO₂激光器的开关电源控制系统。该系统将所需的微处理器功能及产生PWM 波形的功能都集成到一块芯片中,与目前的电源控制系统相比,硬件数量大大减少,提高了集成度。本文首先详细分析了轴快流CO₂激光器控制系统的工作过程和原理,着重研究了激光电源控制系统和开关电源的工作原理。相应的激光电源采用半桥软开关技术,串联谐振并联输出,IGBT 为主控制元件,实现了高频工作、高功率多路输出,响应快速; 脉冲模式工作时避免了开关管的硬开关,减小了高次谐波对电网的干扰; 无需镇流电阻也可实现气体稳定放电等特性。在此基础上,设计出以单片机C8051F015 为核心的电源控制系统,并同激光器的控制系统通过RS-232 接口联成一体,最终实现了单片机对激光器工作模式和输出功率的调控。该系统包括系统初始化、信号检测、算法设计、A/D 转换、PWM 波的生成与输出等。同时,认真分析了单片机系统的干扰源,并采取了相应的抗干扰措施。该系统为数字化控制,所有控制都是在软件中实现的,可以在完全不改变外围电路的情况下,对系统进行升级,完善其功能。同时,数字控制还带来抗干扰性强、可靠性高、调试方便等特点。试验结果证明,该系统具有良好的输出特性,能够完成对开关电源的智能化控制。更多还原

【Abstract】 High power fast axial flow (FAF) CO2 lasers are more and more widely used in industrial laser processing applications. Recently, adoption of the high frequency switch mode power supply and the processing controller based on the programmable chip are the trend of the development of laser technology. The developing direction of current laser switch mode power supply is being digital, being intelligentized, being high-frequency and being modularized. So, this project is to develop a power supply controller based on the single chip for the high power fast axial flow CO2 laser. In the system, the microprocessor function and the function of generation of PWM wave are integrated into a piece of chip. In this paper, the operation and primary principle of the FAF CO2 laser control system are analyzed in detail. The theory of the switch mode power supply system is mainly studied. In the design of the power supply, the main circuit topology frame uses half-bridge series resonant switching and parallel load connection, in which, an IGBT is adopted as the power switches, and features high operation frequency, high output power and fast response. In addition, the IGBT in the switch mode power supply has no hard turn-on or turn –off situation in transition, thus the disturbance to the power system is avoided. Especially, the switch mode power supply system can provide the steady discharge current without any ballast. The power supply controller based on the C8051F015 single chip has been developed, which is connected to the laser control system by the RS-232 series interface, and controls the laser operation mode and laser output power. It includes the system initialization, signal inspection, arithmetic design, A/D transformation, the generation and output of PWM wave, etc.. At the same time, the interference source of the single-chip system, which has been taken the corresponding anti-interference measure, has been analyzed. The system is controlled completely in digital mode, which is realized by the software in the chip, so that we can upgrade the system and perfect its function without changing the hardware. At the same time, digital control can bring the advantages of strong anti-disturbance, high dependability, and debug convenience. The experiment result proves that the control system have excellent input-output characteristic, which can achieve the digital control of the switch mode power supply.更多还原