A platform named EMECS based on embedded Ethernet control system is implemented.A PC running Fedora 6(Linux2.6)works as a central controller.A kit running Linux 2.4 based on Samsung2410A(ARM920t core)works as a remote...A platform named EMECS based on embedded Ethernet control system is implemented.A PC running Fedora 6(Linux2.6)works as a central controller.A kit running Linux 2.4 based on Samsung2410A(ARM920t core)works as a remote controller and a DC motor(ESCA P28HSL18-219/204)made by Portescap Company works as a plant.Firstly,system modeling is presented by analyzing the characteristics of Ethernet and the plant,based on a proposed delay measurement method.Secondly,implementation of the system including program and hardware is described in detail.And then the delay is measured and the control results of the system are tested in three cases with different network loads as well.The platform is proved to have flexibility of running different control algorithms and extensibility of adding nodes.Experiment results demonstrate the validity of the system.展开更多
The present study explores an IEEE1588 Synchronizing System for smart distribution grid based on Industrial Ethernet. The paper first analyzes the communication system in distribution network and then proposed the pro...The present study explores an IEEE1588 Synchronizing System for smart distribution grid based on Industrial Ethernet. The paper first analyzes the communication system in distribution network and then proposed the project of time synchronizing system using IEEE1588 in distribution network. The study focuses on rational clock correcting time region segmentation, selecting the best clock source injection point and multiple redundant methods when correcting time method lose efficacy, etc. The precision of time synchronizing is better than that of 1 millisecond.展开更多
Embedded Ethernet technology has been utilized increasingly widely as the communication mode in the substation automation system(SAS).This paper introduces the current applying situation about embedded Ethernet in SAS...Embedded Ethernet technology has been utilized increasingly widely as the communication mode in the substation automation system(SAS).This paper introduces the current applying situation about embedded Ethernet in SAS First.After analyzing the protocol levels used in SAS based on embedded Ethernet and the differences between the TCP and UDP,UDP/IP is selected as the communication protocol between the station-level and bay-level devices for its real-time characteristic.Then a new kind of implementation of the embedded Ethernet is presented based on hardware protocol stack.The designed scheme can be implemented easily,reduce cost significantly and shorten developing cycle.展开更多
To test the pulse signal of initiating explosive device (IED) in an aircraft,a multi-channel equivalent system for IED based on Gigabit Ethernet transmission is designed according to its electrical parameters. The out...To test the pulse signal of initiating explosive device (IED) in an aircraft,a multi-channel equivalent system for IED based on Gigabit Ethernet transmission is designed according to its electrical parameters. The output voltage of multi-channel equivalent circuit is converted by analog-to-digital converter (ADC). Then the validity of the converted signal is judged by field programmable gate array (FPGA). Finally,it is transmitted the host computer through Gigabit Ethernet for waveform displaying. Compared with the traditional equivalent equipment of IED,the designed system here can not only test the validity of the pulse signal and normal operation of equivalent circuit,but also realize fast and reliable analysis of pulse signal by means of Gigabit Ethernet. It solves the problems of low speed and lag of response of traditional equivalent equipment.展开更多
The resistance spot welding plays an important role in automotive industry. The electrical parameters （power supply voltage, welding current, SCR firing angle and current flow angle） of welding process can reflect t...The resistance spot welding plays an important role in automotive industry. The electrical parameters （power supply voltage, welding current, SCR firing angle and current flow angle） of welding process can reflect the quality of joint and the status of welding equipment, many data acquisition devices designed to collect those parameters have been discussed in many papers, but there is such a deficiency that one computer can only link with an acquisition device. At automobile assembly field, there are hundreds of welding machines working at the same time, so the existing device can not be satisfied with manufacturing demand. To solve the problem, the double-MCU data acquisition device based on Ethernet is discussed in this paper, the data acquisition devices can altogether link with a computer using a HUB, the effective value or the instantaneous value of electrical parameters can be transmitted to the computer over UDP/IP. All the data are read through Ethernet port of a computer using a LabView application, which can process, store and present all data to the user. Finally the experiments prove that the designed Ethernet-based data acquisition system is suitable for practical application.展开更多
Based on the structure and bootloader principle of DSP system, a method for the remote updation, debugging and self-loading of DSP system is developed by Ethernet. Hardware circuit and DM9000 driven program are presen...Based on the structure and bootloader principle of DSP system, a method for the remote updation, debugging and self-loading of DSP system is developed by Ethernet. Hardware circuit and DM9000 driven program are presented and TCP/IP protocol is embedded into DSP. Through the re-mapping of external memory address, it is easy to implement the load of program section selectively and DSP self-boot. The experimental results show that the problem of high cost in system maintenance by conventional field debugging by emulator and the limitation in chip-level boot are resolved.展开更多
基金Supported by CSC(Chinese Scholarship)(Liu Jin Chu[2006]3074)
文摘A platform named EMECS based on embedded Ethernet control system is implemented.A PC running Fedora 6(Linux2.6)works as a central controller.A kit running Linux 2.4 based on Samsung2410A(ARM920t core)works as a remote controller and a DC motor(ESCA P28HSL18-219/204)made by Portescap Company works as a plant.Firstly,system modeling is presented by analyzing the characteristics of Ethernet and the plant,based on a proposed delay measurement method.Secondly,implementation of the system including program and hardware is described in detail.And then the delay is measured and the control results of the system are tested in three cases with different network loads as well.The platform is proved to have flexibility of running different control algorithms and extensibility of adding nodes.Experiment results demonstrate the validity of the system.
文摘The present study explores an IEEE1588 Synchronizing System for smart distribution grid based on Industrial Ethernet. The paper first analyzes the communication system in distribution network and then proposed the project of time synchronizing system using IEEE1588 in distribution network. The study focuses on rational clock correcting time region segmentation, selecting the best clock source injection point and multiple redundant methods when correcting time method lose efficacy, etc. The precision of time synchronizing is better than that of 1 millisecond.
文摘Embedded Ethernet technology has been utilized increasingly widely as the communication mode in the substation automation system(SAS).This paper introduces the current applying situation about embedded Ethernet in SAS First.After analyzing the protocol levels used in SAS based on embedded Ethernet and the differences between the TCP and UDP,UDP/IP is selected as the communication protocol between the station-level and bay-level devices for its real-time characteristic.Then a new kind of implementation of the embedded Ethernet is presented based on hardware protocol stack.The designed scheme can be implemented easily,reduce cost significantly and shorten developing cycle.
文摘To test the pulse signal of initiating explosive device (IED) in an aircraft,a multi-channel equivalent system for IED based on Gigabit Ethernet transmission is designed according to its electrical parameters. The output voltage of multi-channel equivalent circuit is converted by analog-to-digital converter (ADC). Then the validity of the converted signal is judged by field programmable gate array (FPGA). Finally,it is transmitted the host computer through Gigabit Ethernet for waveform displaying. Compared with the traditional equivalent equipment of IED,the designed system here can not only test the validity of the pulse signal and normal operation of equivalent circuit,but also realize fast and reliable analysis of pulse signal by means of Gigabit Ethernet. It solves the problems of low speed and lag of response of traditional equivalent equipment.
文摘The resistance spot welding plays an important role in automotive industry. The electrical parameters （power supply voltage, welding current, SCR firing angle and current flow angle） of welding process can reflect the quality of joint and the status of welding equipment, many data acquisition devices designed to collect those parameters have been discussed in many papers, but there is such a deficiency that one computer can only link with an acquisition device. At automobile assembly field, there are hundreds of welding machines working at the same time, so the existing device can not be satisfied with manufacturing demand. To solve the problem, the double-MCU data acquisition device based on Ethernet is discussed in this paper, the data acquisition devices can altogether link with a computer using a HUB, the effective value or the instantaneous value of electrical parameters can be transmitted to the computer over UDP/IP. All the data are read through Ethernet port of a computer using a LabView application, which can process, store and present all data to the user. Finally the experiments prove that the designed Ethernet-based data acquisition system is suitable for practical application.
文摘Based on the structure and bootloader principle of DSP system, a method for the remote updation, debugging and self-loading of DSP system is developed by Ethernet. Hardware circuit and DM9000 driven program are presented and TCP/IP protocol is embedded into DSP. Through the re-mapping of external memory address, it is easy to implement the load of program section selectively and DSP self-boot. The experimental results show that the problem of high cost in system maintenance by conventional field debugging by emulator and the limitation in chip-level boot are resolved.
