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消除STATCOM对线路距离保护影响方法的研究 被引量:13
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作者 刘青 王增平 张媛 《电力系统保护与控制》 EI CSCD 北大核心 2010年第24期93-98,共6页
从理论上分析了STATCOM对距离保护测量阻抗的影响,STATCOM的装设使测量阻抗中产生了一个附加阻抗,会使阻抗继电器出现欠范围拒动和超越动作的行为。建立了包含STATCOM的双机保护系统模型,并对不同故障类型和不同补偿度时距离保护的误动... 从理论上分析了STATCOM对距离保护测量阻抗的影响,STATCOM的装设使测量阻抗中产生了一个附加阻抗,会使阻抗继电器出现欠范围拒动和超越动作的行为。建立了包含STATCOM的双机保护系统模型,并对不同故障类型和不同补偿度时距离保护的误动进行了仿真,结果表明STATCOM的补偿度越高,距离保护发生误动的情况越严重。根据故障时保护安装处电压幅值的大小与故障点的位置远近有关,提出了故障位置识别的判据及消除距离保护误动的方案,通过判断故障回路是否包含STATCOM而自适应的调整测量阻抗,若故障回路中包含STATCOM,则在原测量阻抗的基础上减去附加阻抗,再与定值进行比较,否则将测量阻抗直接与定值进行比较。对各种故障情况进行仿真验证,结果表明所提方法可以有效地消除距离保护的误动,提高保护的可靠性。 展开更多
关键词 STATCOM 距离保护 附加阻抗 欠范围拒动 超越
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Trinity of Chillingworth
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作者 WANG Ai-yan 《Sino-US English Teaching》 2007年第6期65-70,共6页
Chillingworth is a complicated character in The scarlet letter. His image is a synthesis, or trinity, of the images of God, man of science and Satan, and the novel demonstrates a degradation from God to man of science... Chillingworth is a complicated character in The scarlet letter. His image is a synthesis, or trinity, of the images of God, man of science and Satan, and the novel demonstrates a degradation from God to man of science and finally to a Satan of hatred. In this vicious transformation, his character as man of science plays a key role. Through the development of this character, Hawthorne expresses his criticism to those who lack necessary reverence for human heart and soul. 展开更多
关键词 CHILLINGWORTH DEGRADATION lack of forgivingness man of science over-reacher
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mproved Zone 1 Top-line Tilting Scheme for Polygonal Distance Protection in the Outgoing Line of Type-4 Wind Parks
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作者 Kaiqi Ma Hans Kristian Høidalen +1 位作者 Zhe Chen Claus Leth Bak 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2023年第1期172-184,共13页
The impedance element in distance protection equipment in the outgoing line of a wind park(WP)may be heavily affected by the fault response of the WP.During resistive grid faults,relay over-reach(or under-reach)may ma... The impedance element in distance protection equipment in the outgoing line of a wind park(WP)may be heavily affected by the fault response of the WP.During resistive grid faults,relay over-reach(or under-reach)may manifest,depending on the fault current regulating requirements in the specific grid code deployed in WP and the fault conditions.Aiming at potential solution,i.e.the existing zone 1(fast tripping zone,non-delayed)top-line tilting(Z-1-TLT)function in modern numerical relays,this paper first assesses its adaptability under the WP integrated background.Combining the principle of Z-1-TLT itself and fault modeling to the WP,an improved Z-1-TLT scheme is developed,which can actively compensate for the possible relay overreach or under-reach during resistive faults,utilizing relay side fault quantities only.Aiming at the needless action of the new Z-1-TLT scheme against certain faults,malfunction risk area detection and dead zone detection are introduced as auxiliary criteria to optimize protective efficiency.Simulation results prove the improved Z-1-TLT scheme can effectively improve reliability of distance protection deployed in the WP outgoing line. 展开更多
关键词 Distance protection fault current regulating requirement grid code relay over-reach(under-reach) wind park zone 1 top-line tilting
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