【作者】 高鹏；

【导师】 薛家祥； 冼健威；

【作者基本信息】 华南理工大学 ， 机械工程（专业学位）， 2023， 硕士

【摘要】 等离子体镀膜工艺有良好的应用前景,但是目前使用的镀膜等离子体电源存在功率因数低、性能差、控制不稳定等问题,难以满足日渐提升的镀膜工艺需求。论文以镀膜等离子体电源为研究对象,通过分析等离子体镀膜工艺原理与负载特性,进行电源硬件电路、控制策略以及控制软件设计,研制等离子体镀膜样机,通过镀膜工艺实验探究影响镀膜效果的因素,主要研究内容如下:(1)从等离子体镀膜工艺切入,建立射流等离子体发生器等效负载模型,研究镀膜等离子体发生器的负载特性,指出镀膜等离子体发生器在放电前负载特性等效为电容和电阻的串联电路,在放电后等效为纯电阻电路。(2)设计“整流+Boost PFC+Buck+全桥逆变”的电源总体方案,对主要拓扑的工作模态和控制策略进行分析。进行负载分析,指出使用射流等离子体发生器时全桥逆变电路输出功率更高。设计了电源的输出电压范围为-7k V～7k V,最大输出功率为3k W,工作效率大于90%,可调输出频率的范围为20～40k Hz。(3)研究电源控制策略并进行软件设计。采用数字峰值电流控制策略对Boost PFC电路进行控制,建立小信号模型验证控制的稳定性,引入果蝇优化算法进行PID参数整定。分析影响全桥逆变电路输出瞬时功率的因素,指出当平均功率相同时,放电时间越短,电源输出瞬时功率越大,并由此设计了“PAM+PWM”的混合控制策略对电源进行输出功率调节。在实际电路测试中,当输出功率为1500W时,输入电压幅值提升到392V,输出电流峰值增加到16.8A,瞬时输出功率增大。基于STM32芯片设计电源控制软件,实现数据管理、状态监测以及人机交互等功能。(4)研制等离子体镀膜样机,测试电源关键波形和放电功能、验证优化算法的有效性。结果表明镀膜等离子体电源工作稳定,能够进行宽范围的输出功率调节。进行镀膜工艺实验,探究电源输出功率、工作频率和镀膜腔温度对镀膜效果的影响。对不同材料进行镀膜实验,分析材料的化学成分与微观结构对镀膜效果的影响。更多还原

【Abstract】 The plasma coating process has good application prospects,but the currently used coating plasma power supply has problems such as low power factor,poor performance,and unstable control.It is difficult to meet the increasingly improved coating process requirements.The thesis uses coating plasma power supply as the research object.By analyzing the principles and load characteristics of plasma coating process,the power supply hardware circuit,control strategy,and control software design are studied,and the plasma coating sample machine is developed.The main research content is as follows:(1)Cut in from the plasma coating process.By establishing an equivalent load model of an ions generator in the current,the load characteristics of the coating plasma generator are studied,pointing out that the load characteristics of the coating plasma generator before discharge is equivalent to capacitors and capacitors and capacitances and capacitors.The series of circuits of the resistor are equivalent to pure resistance circuit after discharge.(2)Design the overall solution of the power supply of "rectifier+BOOST PFC+Buck+full bridge inverter" to analyze the working mode and control strategy of the main topology.Perform load analysis,pointing out that the output power of the whole bridge inverter circuit is higher when using a shotmine plasma generator.The output voltage range of the power supply is-7KV ～ 7KV,the maximum output power is 3KW,the work efficiency is greater than 90%,and the range of the adjustable output frequency is 20 ～ 40 k Hz.(3)Study the power control strategy and carry out software design.The BOOST PFC circuit is controlled by the digital peak current control strategy,the stability of the small signal model verification and control is established,and the Fruit-fly Optimization Algorithm is introduced for PID parameters.The analysis affects the instantaneous power output of the whole bridge inverter circuit,pointing out that when the average power is the same,the shorter the discharge time,the greater the instantaneous power of the power supply output,and the mixed control strategy of "PAM+PWM" is designed Power adjustment.In the actual circuit test,when the output power is 1500 W,the input voltage amplitude value is increased to 392 V,the peak of the output current is increased to 16.8A,and the instant output power increases.Based on the STM32 chip,power control software,data management system,status monitoring system,and human-computer interaction are realized.(4)Develop plasma coating sample machine.Test the power supply key waveform and discharge function,verify the effectiveness of the optimization algorithm,and explore the main factor affecting the effect of coating.The experimental results show that the power supply of coating plasma is stable and can be adjusted in a wide range of output power.Perform the coating process experiment to explore the effects of power output power,operating frequency,and coating cavity temperature on the coating effect.Perform coating experiments on different materials,and analyze the effects of chemical composition and micro-structures of the material on the coating effect.更多还原