| 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.
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