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继电保护装置光隔开入引起保护误动的原因分析
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作者 舒征 《中国新技术新产品》 2011年第19期118-118,共1页
目前,我国继电保护装置及许多自动化装置的开关量输入(简称开入)回路大部分采用光电隔离输入,采用此方法有效地隔离了外部强电对微机装置的电磁干扰,外部采用直流强电保证了开入的可靠性,避免了装置内部弱电远距离引出造成的不安全和不... 目前,我国继电保护装置及许多自动化装置的开关量输入(简称开入)回路大部分采用光电隔离输入,采用此方法有效地隔离了外部强电对微机装置的电磁干扰,外部采用直流强电保证了开入的可靠性,避免了装置内部弱电远距离引出造成的不安全和不稳定因素,造价也相对低廉。但在现场应用过程中,由于设计和使用不规范带来的继电保护装置误动事故频繁发生,并且大部分发生在220kv和500kv的高电压等级变电站,严重威胁电力系统的安全和经济运行。 展开更多
关键词 继电保护 误动的原因分析 隔离开入
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Fabrication and Numerical Simulation of a MicromachinedContact Cantilever RF-MEMS Switch 被引量:3
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作者 孙建海 崔大付 肖疆 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第2期309-312,共4页
This paper reports a contact cantilever MEMS switch. The designed switch has a metal cantilever that acts as an electrostatically activated switch with processing options to achieve dielectric isolation of the control... This paper reports a contact cantilever MEMS switch. The designed switch has a metal cantilever that acts as an electrostatically activated switch with processing options to achieve dielectric isolation of the controlvoltage path from the signal path. To obtain good material properties,an ANSYS FEA tool is used to optimize the structure. The RF MEMS switch is fabricated via a surface micromachining process. The switch has an actuation voltage of 12V,which is close to the simulated value of 11V. The measured and the HFSS simulated isolations are both higher than - 20dB from 0.05 to 10GHz. The measured insertion loss is less than - 0.9dB, relatively larger than the simulated loss of less than - 0.2dB from 0.05 to 10GHz. This is because a contact resistance introduced due to poor physical contact between the bottom lines and the metal cantilever. 展开更多
关键词 cantilever RF-MEMS switch insertion loss ISOLATION
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