1) negative sequence overcurrent
负序过电流
1.
Based on calculation and statistics, analysis of sensitivity of far back up protection of transformer at 10kV side and 10kV distribution line,this paper proposes to improve protective configuration about transformer and distribution line that is adding negative sequence overcurrent protection as supplement for back up protection of 10kV system phase-to-phase fault.
通过对变压器10kV侧及10kV配网线路相间过流远后备灵敏度的计算、统计、分析,提出增加变压器和配网线路保护配置:增设负序过电流保护作为10kV系统相间短路后备保护的补充,使对同一点故障的灵敏度及切除率由11。
2) resistance type negative sequence filter
负序电流滤过器
1.
The structure and feature of reactance type differential relay and resistance type negative sequence filter are introduced.
介绍了电抗型差动继电器、电阻型负序电流滤过器的结构原理 ,分析了频率变化对电抗型差动继电器、电阻型负序电流滤过器特性的影响 ,提出了采用工频电源代替 1 0 0 Hz电源进行元件调整试验的可行性。
3) negative sequence current
负序电流
1.
Design and application of generator negative sequence current monitoring instrument;
发电机负序电流监测仪的设计与实现
2.
Much more attention is paid to the analysis of the method how to define the characteristic curves of phase sensitive symmetrical short circuit protection, the design of negative sequence current filter and the definition of the mathematical model of overload.
重点介绍了对称短路相敏保护特性曲线的确定方法 ,设计了负序电流滤波器 ,建立了过负荷保护的数学模型 。
3.
Aiming to characteristic of 3-phase to 2-phase power supply based on balance transformer, a new current balance compensation method utilizing inverter is proposed, which is mainly used to compensate negative sequence current.
从而使平衡变压器两相侧的输出电流对称,消除平衡变压器三相侧产生负序电流的条件,达到三相电流对称的目的。
4) negative current
负序电流
1.
Analysis of negative current in switching tests for load tap on-load tap-changers of transformers;
变压器有载分接开关切换试验中负序电流分析
2.
Analysis of the operation of the generator negative current protection impacted on by the electric railway loading
电气化铁路负序电流对发电机负序过流保护的影响
3.
According to the frequency excursion in power systems, this paper proposes a detecting method of harmonic negative current instructions.
针对电网出现的频率偏差 ,提出一种谐波负序电流指令的检测方法。
5) negative-sequence current
负序电流
1.
Electric railways have witnessed great development in Chinese railway system;however,the serious negative-sequence current,harmonics,reactive power and load fluctuation during the running process influence the electric power quality.
电气化铁道在全国铁道系统中都有了很大的发展,然而运行中易产生严重的负序电流、谐波、无功及负荷波动,对电能质量有一定程度的影响。
2.
The running state of three-phase asynchronous motor is monitored by negative-sequence current method and zero-sequence current method.
利用负序电流法和零序电流法监测三相异步电动机的运行状态,并设计电动机保护电路和PLC的控制梯形图,用FX系列PLC进行故障类型判别和报警处理,设计方案原理简单、工作可靠。
3.
The harm of negative-sequence current produced by electric train is analyzed.
介绍了沪杭电气化铁道工程的简况以及电气化列车运行时输出的负序电流的危害。
6) negative sequence electric current
负序电流
1.
Fully considering the hot accumulation and the negative sequence electric current, using the combined heat balance differential equation methods.
在充分考虑热积累和负序电流效应的前提条件下,通过求解热平衡微分方程的方法,研究了电动机运行过程中的任意时刻的温度变化情况,模拟出电动机的温度实际变化过程,为过载保护提供了依据。
2.
This paper introduces the impac of the negative sequence electric current on the power system whichcaused by traction load, and the way to reduce it, explains the impairment of the unbalanced harmonic on the power systemin the views of project and economy, and puts forward a series of measures for preventing the impairment.
本文介绍牵引负荷在电力系统中引起的负序电流对电力系统的影响及降低和限制负序电流的措施;从工程和经济两个角度说明了不平衡谐波对电力系统的危害,并提出了一些应对措施;针对电铁负荷功率因数较低的现象,分析了无功补偿的必要性以及目前存在的问题和解决措施。
3.
This paper introduces the impact of the negative sequence electric current on the power system which caused by traction load,and the way to reduce it.
文章介绍了牵引负荷在电力系统中引起的负序电流对电力系统的影响及降低和限制负序电流的措施;针对电气化铁路负荷功率因数较低的现象,分析了无功补偿的必要性以及目前存在的问题和解决措施。
补充资料：交流电气化铁路的负序电流和负序电压
交流电气化铁路的负序电流和负序电压
the negative sequence current and voltage produced by AC elec-tric railway
处为最大，随着负序电流逐渐分散进人电力系统，系统各处的负序电压水平将逐渐下降。YN，d一l:v.v:单相平衡接线11:重臂负荷I]l=轻价负荷月=111/11两，负荷功率因教相同0。250。5751。0 图2不同接线牵引变电所的负序电流系数 允许标准不同类型发电机的负序承受能力不同，为此，首先应根据有关电机制造标准，选择允许的负序标准。在缺少电机制造标准规定时，可参照以下规定:当汽轮发电机在额定工况连续运行时，三相电流差不应超过10%，水轮发电机三相电流差不应超过20%;有关电力系统公共连接点的三相电压不平衡度，中国国家标准规定:“正常的电压不平衡度允许值为2%，短时不得超过4%”。 改善措施主要有: (1)对电气化铁路各牵引变电所实行进线相序轮换，减少电气化区段的综合负序。 (2)采用平衡接线变压器，常用的接线型式有斯科特、列布兰、变形伍德布里奇等方式。 (3)在受负序电流影响最大的电力系统分支回路中加装电抗器，以限制进人该支路的负序电流。i旧01一u dlanqihua tielu de fuxud一anl旧he fuxud一onya交流电气化铁路的负序电流和负序电压(thenegative Sequenee eurrent and voltage produeedby AC eleetrie railway)交流电气化铁路的单相牵引负荷会造成电力牵引变电所一次侧三相负荷电流不平衡，任一三相不平衡系统均可用对称分量法分解成正序、负序和零序三组对称分t的盈加，从而在电力系统中产生负序电流和负序电压.接人电力系统线电压间的单相负荷不产生零序分量，只有正序和负序分t。负序电流、负序电压的有害影响有: (l)可在同步发电机转子中产生附加损耗和局部发热，造成系统出力下降， (2)负序电流产生的负序转矩，使发电机振动，影响安全运行; (3)增大系统中各翰电环节的损耗; (4)负序电压的存在对系统中三相电动机用户产生不利影响，造成电动机三相电流不对称和附加损耗，使出力下降并危及电动机安全。 牵引变电所的负序电流电力牵引变电所负序电流取决于两供电臂负荷的相位和幅值，因此可以把牵引变电所看作是一个负序电流源. 图1示出变压器为YN，dll接线的三相牵引变电所在两份用电功率因数相同时的负序电流相盆图.图1的上方为臂电流和变压器二次绕组的三相电流相量;中间为正序电流相量;下方为负序电流相t.不同供电臂产生的负序电流有1200相位差。
说明：补充资料仅用于学习参考，请勿用于其它任何用途。
参考词条