The automation technology of electric energy measurement covers all levels of electric energy measurement points. The electric energy data acquisition of power users has realized remote automatic acquisition. The tool...The automation technology of electric energy measurement covers all levels of electric energy measurement points. The electric energy data acquisition of power users has realized remote automatic acquisition. The tool for remote automatic collection of electric energy data is various metering automation terminals installed on the site. The data transmission of the automation terminal depends on various communication channels. When the field signal strength is insufficient and the communication module of the metering automation terminal cannot work normally, the terminal is offline and the data collection fails. At this time, it is necessary to solve the problem of insufficient signal through other methods, ensure the real-time communication of the terminal. This paper will introduce a technology to enhance the communication ability of terminal communication module, and illustrate the whole picture of the device through practical cases.展开更多
The fiber Bragg grating （FBG） sensing technology was used to monitor the situation of a crevice of the continuous beam joint and rails near rail expansion devices on a viaduct of the urban railway. The monitoring it...The fiber Bragg grating （FBG） sensing technology was used to monitor the situation of a crevice of the continuous beam joint and rails near rail expansion devices on a viaduct of the urban railway. The monitoring items consisted of the rail temperature, rail displacement, viaduct beam displacement, and strain of sliding rail in the rail expansion device section. The strain sensor was a prefabricate FBG strain gauge, the displacement sensor with different scales used an FBG stress ring, and the FBG of the temperature sensor was pre-drawn and fixed in a metal tube. Compensation sensors were used to balance environmental temperature changes. All FBGs were suspended adhered, therefore the chirped phenomenon of the FBG reflection peak was avoided, and the measurement accuracy was improved. The monitoring results matched to the manual test and theoretical estimation.展开更多
文摘The automation technology of electric energy measurement covers all levels of electric energy measurement points. The electric energy data acquisition of power users has realized remote automatic acquisition. The tool for remote automatic collection of electric energy data is various metering automation terminals installed on the site. The data transmission of the automation terminal depends on various communication channels. When the field signal strength is insufficient and the communication module of the metering automation terminal cannot work normally, the terminal is offline and the data collection fails. At this time, it is necessary to solve the problem of insufficient signal through other methods, ensure the real-time communication of the terminal. This paper will introduce a technology to enhance the communication ability of terminal communication module, and illustrate the whole picture of the device through practical cases.
文摘The fiber Bragg grating （FBG） sensing technology was used to monitor the situation of a crevice of the continuous beam joint and rails near rail expansion devices on a viaduct of the urban railway. The monitoring items consisted of the rail temperature, rail displacement, viaduct beam displacement, and strain of sliding rail in the rail expansion device section. The strain sensor was a prefabricate FBG strain gauge, the displacement sensor with different scales used an FBG stress ring, and the FBG of the temperature sensor was pre-drawn and fixed in a metal tube. Compensation sensors were used to balance environmental temperature changes. All FBGs were suspended adhered, therefore the chirped phenomenon of the FBG reflection peak was avoided, and the measurement accuracy was improved. The monitoring results matched to the manual test and theoretical estimation.
