【作者】 马磊；

【导师】 李清泉；

【作者基本信息】 山东大学 ， 高电压与绝缘技术， 2008， 硕士

【摘要】 利用介质阻挡放电的方法在大气压下产生低温等离子体,是当前等离子体学科研究的热点,因此用于介质阻挡放电的高频高压脉冲电源成为研究的重点。本课题以串联谐振型高频脉冲电源为研究对象,采用容性移相PWM控制和频率跟踪技术,设计出适合于介质阻挡放电负载的高频高压电源,解决了电源在高频率下功率因数低、开关应力大的问题。利用电源专用的数字信号控制芯片dsPIC30F2020实现了数字化控制系统的设计,并对影响介质阻挡放电的因素进行了试验研究。本文的主要工作内容为:1.通过对介质阻挡放电负载特性分析的基础上,选择串联谐振电路作为主电路,采用移相PWM和频率跟踪的控制方案。重点比较了基于电流频率跟踪的移相PWM控制下的三种工作方式即感性、容性和谐振状态下电路的负载特性和换流过程,得到容性移相PWM控制适合于使用IGBT为开关器件的串联谐振电路,易于实现软开关技术。在频率跟踪环节选择上,对比传统的模拟锁相环技术,提出采用数字化的频率跟踪技术,并设计了基于数字控制芯片的频率跟踪方案。2.在理论分析的基础上,设计了介质阻挡供电电源的主电路参数,重点研究了容性移相PWM控制策略和电流频率跟踪的数字化实现,并设计了基于dsPIC30F2020的电流频率跟踪的容性移相PWM控制的数字化控制系统,包括电压电流采样电路、电流过零采样电路、发生器端电压PID控制等环节。通过对电流的频率跟踪,结合发生器端电压的PID闭环控制,实现了容性移相PWM控制策略和功率调节。3.在实验室组建了介质阻挡放电实验系统,研究了施加电压幅值、气隙距离、阻挡介质的厚度和介电常数、添加筛网、电极的结构等因素对DBD放电特性的影响,结果表明,DBD的放电功率随施加电压幅值和介质的介电常数的增加而增加,随气隙距离和介质厚度的增加而减小。在阻挡介质与电极间添加金属筛网能使放电更均匀,针-板电极比板-板电极在同样条件下能使放电更稳定。更多还原

【Abstract】 How to use dielectric barrier discharge (DBD) to come out low-temperature plasma under atmospheric pressure has become hotspot in this research field. Hence, to develop discharge power supply used in DBD is the main question.This paper studies on the capacitive phase-shift PWM control series resonant load full Inverter DBD type power supply. Frequency Tracing Technology is used in DBD load circuit. The experiment results show that the proposed method has the virtues of high power factor and low switch stress. The control system of power supply based on dsPIC30F2020 controller has been designed. The main achievements obtained by this dissertation are:Firstly, by analyzing dielectric barrier discharge series resonant load Inverter and its power regulation method, according to frequency tracing technology of the load current, capacitive phase shifting PWM control full bridge inversion series resonant load circuit is applied to DBD type power supply. The paper mainly analyzes operating process under different operation modes of the inverter. Compared with inductive phase-shift PWM and phase-shift resonant PWM, the capacitive phase-shift PWM has a small frequency fluctuating and fit the inverter that consists of IGBTs. The paper discusses the frequency tracking technology and gives the phase locked loop based on digital electronic circuit.Secondly, the parameter of main circuit is designed in the paper. One kind of digital control system of power supply based on microchip dsPIC30F2020 has been designed, which realize the digitization. According to the frequency tracing technology of the load current, and the generator voltage which is controlled by PID closed-loop, capacitive phase shifting PWM control strategy and the power regulation have been realized.Thirdly, DBD equipment is set up in laboratory. By a series DBD experiment, the influences of the applied voltage, the gas gap distance, and the thickness and dielectric permittivity of the barrier on the discharge characteristics are studied, The results show that the value of power dissipated increases with the increasing of applied voltage and dielectric permittivity of the barrier, and decrease with the increasing of gas gap distance and the thickness of barrier.更多还原