【作者】 张栋；

【导师】 王志强；

【作者基本信息】 华南理工大学 ， 电力电子与电力传动， 2010， 硕士

【摘要】 强等离子体具有温度高、能流密度高、化学活性高、可控性好等特点,在固体垃圾以及危险废物的资源化处理、电站燃煤点火、金属冶炼、煤的汽化活化、焊接、喷涂以及切割等领域具有广阔的应用前景。要实现强等离子体技术的全面推广,可靠性高、控制性能好的等离子体电源装置是其中的关键。相比传统电源,高频逆变电源具有节能20-30%、省材60-70%、网电冲击小以及控制性能好等优点,但随着功率增强,因并联均流、温升、电磁干扰、寄生参数等因素造成的可靠性问题已成为制约其推广应用的技术瓶颈。本文在国家自然科学基金的资助下,瞄准制约大功率等离子体逆变电源装置产业化的技术瓶颈问题,研究以ARM和RTOS为核心的嵌入式控制策略,实现强电弧等离子体逆变电源装置功率的增强和能量的高效可靠传递。本设计的强等离子体逆变电源采用智能节点型模块式结构,整个电源装置由多个分散的模块式电源构成。各模块式电源相当于一个智能节点,均具有自律可控性,能够依靠各自的智能控制器分别进行自律管理,不受其他模块的控制与干涉。任何智能节点在发生故障时,均能及时自动切除脱离系统,并在维修后可正常工作时自动切入系统,不会干扰和影响其他智能节点的自律管理以及整个等离子体电源系统的正常运行。智能节点由智能控制器和主电路两大部分构成。主电路采用全桥拓扑结构。以具备Coxter-M3为内核的ARM微处理器LM3S8971为智能控制器的控制核心,设计了完善的IGBT驱动电路、信号采样和故障检测电路以及通信接口电路,构建了嵌入式控制器硬件平台;利用ARM微处理器自带的RTOS实时内核,根据电源工作流程及输出特性,对智能节点的软件系统进行了嵌入式设计,划分了各任务的优先级和任务进程,使得代码结构更加清晰,可读性更强,系统升级和移植更为灵活方便。设计了基于ARM+CPLD双芯控制结构的人机交互系统,利用ARM微处理器LM3S818的控制和运算能力对人机交互过程进行程序控制,同时利用CPLD丰富的I/O引脚和可灵活编程的特点,把ARM发送的命令转化为数码管和LED的显示;通过扩展的RS232接口,实现了人机交互系统与智能节点控制器的数字通信控制。最后,对所设计的等离子体智能节点来进行了实验研究。本课题设计的等离子体电源主要用于冶炼加热,根据工艺设置给定参数,各智能节点之间通过CAN总线控制网络进行连接,并通过CAN/USB转换模块与远程监控计算机进行通信。实验波形以及远程综合管理系统界面显示的数据验证了本设计的正确性。更多还原

【Abstract】 With the power electronics technology, IC integrated manufacturing technology of rapid development, and with cost reduced of digital signal processor, traditional industries are facing unprecedented great revolution and developing to direction of smart module, digital, network.In recent years, because strong plasma is with high temperature and high thermal conductivity, energy concentration and other characteristics, so, it has a high processing efficiency in solid waste, hazardous waste, especially intractable or has special requirements for pollutants, and also widely used in machinery processing(welding, cutting, painting, etc.),metallurgy, materials and other fields. High reliability and good control performance of power devices is a key factors to achieve application and promotion of strong plasma arc plasma technology. Compared to the traditional power, high frequency inverter can save energy 20-30%, save material 60-70%, have good control performance and less electric shocks and to grid, but parallel flow, temperature rise of devices, electromagnetic interference and parasitic parameters is technical bottlenecks in the reliability of it with the power increase in marketing application. In this paper, funded by the National Natural Science Fund, aimed at technological bottlenecks of strong plasma inverter in industry, research it which ARM and RTOS as the core of the embedded control strategies to achieve more energy efficient and reliable delivery of strong plasma inverter power.Designing the strong plasma inverter by use intelligent node structure with modular, The power supply is compose by multi-distributed modular power, every decentralized node supply has the ability of self-controllable, which relying on its self-control chip managed own and has little interference form other nodes module.In this power system, when any node fails, the node can be automatically removed form the system in time and can automatically join the system after fault clearing. Which does not interfere and affect self-management of other nodes power, and the plasma power system can normally run.Intelligent node is consist of the intelligent controller and the main circuit, main circuit adopt full-bridge circuit topology.The design of each intelligent node uses ARM’s latest LM3S8971 chips base on Coxter-M3 core for control chip of the main control circuit. Constructing embedded controller hardware platform by well-designed IGBT driver circuit, signal sampling and fault detection circuit and the communication interface circuit .Designing program code of the task process of nodes power workflow and according to the workflow and output characteristic of power based on RTOS of chips, which makes the program codes more clear and more readable,and makes system more flexible and convenient in upgrades and migration.Designing human-computer interaction based dual-core ARM+CPLD control structure, and implementing program control to the human-computer interaction by using control and computing ability of LM3S818 ARM microprocessor, and the CPLD have the rich I / O pins、flexible programming the characteristics. When command from ARM sent into the digital tube and LED to display, human-computer interaction systems and intelligent node controller can achieve digital communication by extending the RS-232 interface.Finally, using plasma nodes power designed in the laboratory to carry out experiments, because the plasma power supply has wide range of applications, the plasma power supply of the design is used for metallurgical welding in development phase of the subject, so, according to the welding technique to set parameter of welding. Every nodes power is connect to PC by CAN bus and carry out experiment begin.By observing the waveform and display data, the design of the hardware circuit and software program code is correct in the subject.更多还原