Pulse width modulation （ PWM） drive control digitalization is the key for the full digital invert power supply. New ideas are proposed, which are based on field programmable gate array （ FPGA ）. First, digital PWM...Pulse width modulation （ PWM） drive control digitalization is the key for the full digital invert power supply. New ideas are proposed, which are based on field programmable gate array （ FPGA ）. First, digital PWM principles are discussed. The primary and secondary current characteristics are analyzed when the transformer is in both normal and magnetic bias conditions. Second, two digitalization methods are put forward after the research on PWM adjustment principles, which are based on the primary current feedback. Though the two methods could restrain magnetic bias, their realization is difficult. A new method is researched on double close-loops to overcome the above shortcomings, which uses the secondary current as the feedback signal and the primary current as the protection signal. Finally, the secondary current control made is discussed and realized. Welding experimental results show that the method has strong flexibility and adaptability, which can be used to realize the full digital welding power supply.展开更多
This paper presents a new thermal computer, which is driven by heat current and not electricity current. The basic thermal logic gate, such as thermal logic AND gate. thermal logic NOT gate, thermal logic OR gate are ...This paper presents a new thermal computer, which is driven by heat current and not electricity current. The basic thermal logic gate, such as thermal logic AND gate. thermal logic NOT gate, thermal logic OR gate are discussed in this paper. Compared with electronic computer, it can work at some special environment, such as high temperature and high pressure Consequently, the heat computer is not only a new special computer, but also a lot of new heat computation cell or device could be invented in the future. The thermal computer and control device are a new thermal energy machines powered by heat energy, it is significant for the environmental protection, energy usage and developed and new discipline development.展开更多
To meet the demands for highly advanced components with ultra precise contour accuracy and optical surface quality arising in the fields of photonics and optics, automotive, medical applications and biotechnology, con...To meet the demands for highly advanced components with ultra precise contour accuracy and optical surface quality arising in the fields of photonics and optics, automotive, medical applications and biotechnology, consumer electronics and renewable energy, more advanced production machines and processes have to be developed. As the complexity of machine tools rises steadily, the automation of manufacture increases rapidly, processes become more integrated and cycle times have to be reduced significantly, challenges of engineering efficient machine tools with respect to these demands expand every day. Especially the manufacture of freeform geometries with non-continuous and asymmetric surfaces requires advanced diamond machining strategies involving highly dynamic axes movements with a high bandwidth and position accuracy. Ultra precision lathes additionally equipped with Slow Tool and Fast Tool systems can be regarded as state-of-the-art machines achieving the objectives of high quality optical components. The mechanical design of such ultra precision machine tools as well as the mechanical integration of additional highly dynamic axes are very well understood today. In contrast to that, neither advanced control strategies for ultra precision machining nor the control integration of additional Fast Tool systems have been sufficiently developed yet. Considering a complex machine setup as a mechatronic system, it becomes obvious that enhancements to further increase the achievable form accuracy and surface quality and at the same time decrease cycle times and error sensitivity can only be accomplished by innovative, integrated control systems. At the Fraunhofer Institute for Production Technology IPT a novel, fully integrated control approach has been developed to overcome the drawbacks of state-of-the-art machine controls for ultra precision processes. Current control systems are often realized as decentralized solutions consisting of various computational hardware components for setpoint generation, machine control, HMI （human machine interface）, Slow Tool control and Fast Tool control. While implementing such a distributed control strategy, many disadvantages arise in terms of complex communication interfaces, discontinuous safety structures, synchronization of cycle times and the machining accuracy as a whole. The novel control approach has been developed as a fully integrated machine control including standard CNC （computer numerical control） and PLC （programmable logic controller） functionality, advanced setpoint generation methods, an extended HMI as well as an FPGA （field programmable gate array）-based controller for a voice coil driven Slow Tool and a piezo driven Fast Tool axis. As the new control system has been implemented as a fully integrated platform using digital communication via EtherCAT, a continuous safety strategy could be realized, the error sensitivity and EMC susceptibility could be significantly decreased and the overall process accuracy from setpoint generation over path interpolation to axes movements could be enhanced. The novel control at the same time offers additional possibilities of automation, process integration, online data acquisition and evaluation as well as error compensation methods.展开更多
文摘Pulse width modulation （ PWM） drive control digitalization is the key for the full digital invert power supply. New ideas are proposed, which are based on field programmable gate array （ FPGA ）. First, digital PWM principles are discussed. The primary and secondary current characteristics are analyzed when the transformer is in both normal and magnetic bias conditions. Second, two digitalization methods are put forward after the research on PWM adjustment principles, which are based on the primary current feedback. Though the two methods could restrain magnetic bias, their realization is difficult. A new method is researched on double close-loops to overcome the above shortcomings, which uses the secondary current as the feedback signal and the primary current as the protection signal. Finally, the secondary current control made is discussed and realized. Welding experimental results show that the method has strong flexibility and adaptability, which can be used to realize the full digital welding power supply.
基金Acknowledgment： The paper was supported by the Nature Science Foundation of China （No. 50876034）, Ph.D. Science Foundation of Ministry. of Education of China （No. 20040487039）： Key Discipline Construction Foundation of Shanghai Education Commission （No. J5180｜）： Science Foundation of Shanghai Education Commission （No. 08ZY79） SSPU Science Foundation （No. DZ207004）.
文摘This paper presents a new thermal computer, which is driven by heat current and not electricity current. The basic thermal logic gate, such as thermal logic AND gate. thermal logic NOT gate, thermal logic OR gate are discussed in this paper. Compared with electronic computer, it can work at some special environment, such as high temperature and high pressure Consequently, the heat computer is not only a new special computer, but also a lot of new heat computation cell or device could be invented in the future. The thermal computer and control device are a new thermal energy machines powered by heat energy, it is significant for the environmental protection, energy usage and developed and new discipline development.
文摘To meet the demands for highly advanced components with ultra precise contour accuracy and optical surface quality arising in the fields of photonics and optics, automotive, medical applications and biotechnology, consumer electronics and renewable energy, more advanced production machines and processes have to be developed. As the complexity of machine tools rises steadily, the automation of manufacture increases rapidly, processes become more integrated and cycle times have to be reduced significantly, challenges of engineering efficient machine tools with respect to these demands expand every day. Especially the manufacture of freeform geometries with non-continuous and asymmetric surfaces requires advanced diamond machining strategies involving highly dynamic axes movements with a high bandwidth and position accuracy. Ultra precision lathes additionally equipped with Slow Tool and Fast Tool systems can be regarded as state-of-the-art machines achieving the objectives of high quality optical components. The mechanical design of such ultra precision machine tools as well as the mechanical integration of additional highly dynamic axes are very well understood today. In contrast to that, neither advanced control strategies for ultra precision machining nor the control integration of additional Fast Tool systems have been sufficiently developed yet. Considering a complex machine setup as a mechatronic system, it becomes obvious that enhancements to further increase the achievable form accuracy and surface quality and at the same time decrease cycle times and error sensitivity can only be accomplished by innovative, integrated control systems. At the Fraunhofer Institute for Production Technology IPT a novel, fully integrated control approach has been developed to overcome the drawbacks of state-of-the-art machine controls for ultra precision processes. Current control systems are often realized as decentralized solutions consisting of various computational hardware components for setpoint generation, machine control, HMI （human machine interface）, Slow Tool control and Fast Tool control. While implementing such a distributed control strategy, many disadvantages arise in terms of complex communication interfaces, discontinuous safety structures, synchronization of cycle times and the machining accuracy as a whole. The novel control approach has been developed as a fully integrated machine control including standard CNC （computer numerical control） and PLC （programmable logic controller） functionality, advanced setpoint generation methods, an extended HMI as well as an FPGA （field programmable gate array）-based controller for a voice coil driven Slow Tool and a piezo driven Fast Tool axis. As the new control system has been implemented as a fully integrated platform using digital communication via EtherCAT, a continuous safety strategy could be realized, the error sensitivity and EMC susceptibility could be significantly decreased and the overall process accuracy from setpoint generation over path interpolation to axes movements could be enhanced. The novel control at the same time offers additional possibilities of automation, process integration, online data acquisition and evaluation as well as error compensation methods.
