电网三段式零序电流保护.doc

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1、【精品文档】如有侵权，请联系网站删除，仅供学习与交流电网三段式零序电流保护.精品文档.第一章 设计题目系统接线图如下图(图1.1)，发电机以发电机-变压器组方式接入系统，开机方式为两侧各开1台机，变压器T5 1台运行。参数为：,线路阻抗,;试对1、2、3、4进行零序保护的设计。图1.1系统接线图1.1具体设计要求本设计主要对系统进行零序保护的设计。要求完成对1、4点的零序保护的设计。通过对1、4点的保护方式的分析，进行零序三段电流保护，并对设计的保护进行灵敏度校验和整定时间的确定,并进行有关设备的选择和评价。第二章 分析要设计的课题内容2.1设计规程继电保护装置应满足可靠性、选择性、灵敏性和速

2、动性的要求，110220kV有效接地电力网线路，应按下列规定装设反应接地短路和相间短路的保护装置。(1)对于接地短路：装设带方向和不带方向的阶段式零序电流保护；零序电流保护不能满足要求时，可装设接地距离保护，并应装设一段或两段零序电流保护作为后备保护。(2)对于相间短路：单侧电源单回线路，应装设三相多段式电流或电压保护，如不能满足要求，则应装设距离保护；双侧电源线路宜装设阶段式距离保护。2.2本设计的保护配置2.2.1主保护（零序电流保护）的配置电力系统正常运行时是三相对称的，其零序、负序电流值理论上是零。多数的短路故障是不对称的，其零、负序电流电压会很大，利用故障的不对称性可以找到正常与故障

3、的区别，并且这种差别是零与很大值得比较，差异更为明显。2.2.2后备保护（距离保护）配置距离保护是利用短路发生时电压、电流同时变化的特征，测量电压与电流的比值，该比值反应故障点到保护安装处的距离，如果短路点距离小于整定值，则保护装置动作。2.3绘制等效电路图绘制三序电压等值网络图如图1;图2;图3。图1正序网络图2负序网络图3零序网络第三章 短路电流及残压计算3.1保护短路点的选取 母线A处分别发生单相接地短路和两相接地短路，求出流过保护2的最大零序电流。 母线B处分别发生单相接地短路和两相接地短路，求出流过保护1和4的最大零序电流。 母线C处分别发生单相接地短路和两相接地短路，求出流过保护3

4、的最大零序电流。3.2短路电流的计算整理线路参数: (1)B母线单相接地短路时，有上述三序网络图得故障端口正序阻抗： 故障端口负序阻抗: 故障端口零序阻抗:所以系统单相接地短路的复合序图如图3.1所示：图3.1 单相接地短路的复合序图故障端口的零序电流为：=1.514kA; KA KA当B母线发生两相接地短路时,故障端口各序阻抗与单相接地的相同，可画出系统两相接地短路的复合时序图如图3.3所示：图3.3 两相接地短路的复合序图 KA KA KA由以上计算可得：I0.4max=0.304KA;I0.1max=0.241KA同理得：A母线分别发生单相接地和两相接地短路时的等值网络。 故障端口正序阻

5、抗为: 故障端口负序阻抗为:; 故障端口零序阻抗为:则最大短路零序电流: 单相接地短路时 KA 两相接地短路时 5.068故障端口正序电流 由以上计算可得I0.2max=0.177KA同理得：C母线分别发生单相接地和两相接地短路时的等值网络。单相接地短路时，故障端口正序阻抗为:故障端口负序阻抗为：故障端口零序阻抗为：则最大短路零序电流: 单相接地短路时: 在零序网络中按照零序导纳分配零序电流从而得到此时的流过保护1、4出的零序电流分别为 两相接地短路时:4.997端口正序电流：零序电流： 由以上计算可得：I0.3max=0.176KA第四章 保护的配合及整定计算4.1整定原则：(例如保护1处)

6、(1)躲过被保护线路末端接地短路使得最大零序电流，即 (4.1)为可靠系数，一般取1.11.25；为保护处零序电流。(2)零序段与下一条线路段配合，即与3的段配合的零序电流为： (4.2) 为可靠系数，取1.17；为分之系数。 （3）按照躲过相邻线路出口处发生相间短路时的最大不平衡电流整定整定计算公式： (4.3) (4.4) 式中为短路电流中非周期分量影响系数，取1.5；为电流互感系数，取0.5；为电流互感误差，取0.1；为端点最大电流。为靠可系数，取1.2。4.2保护1处4.2.1保护1零序段零序段躲开下一条线路出口处单相或两相接地时出现的最大零序电流由式4.1得: 4.2.2保护1零序段

7、零序段与下一条线路段配合，即与3的段配合由式4.1得: (4.5)分之系数 =; (4.6) 由式结果带入4.2中可得1零序段电流为： (4.7) 灵敏度校验灵敏度校验公式： (4.8)式中为端点最小电流；为保护电流将数据带入4.7式中得灵敏度系数1.15动作时间保护1的段为零序速断电流保护，故动作时间均为0s,保护1的段为限时零序电流速断，比段延迟一个t,故保护1的段的动作时间为0.5s4.2.3保护1零序段零序段保护按躲开末端最大不平衡电流得： (4.9)将4.9结果带入4.4中得动作电流 (4.10) 作为近后备保护 满足要求作为远后备保护 满足要求保护1的段保护与下段线路配合，动作时间

8、比段的动作时间延迟t，故动作时间为1s.4.3保护4处4.3.1保护4零序段零序段躲开下一条线路出口处单相或两相接地时出现的最大零序电流由式4.1得: (4.11) 4.3.1保护4零序段零序段与下一条线路段配合，即与保护2的段配合由式4.1得: (4.12) 分之系数 =3.45; (4.13) 由式（4.12）、（4.13）结果带入4.2中可得1零序段电流为： (4.14) 灵敏度校验 灵敏度校验公式： (4.15) 式中为端点最小电流；为保护电流将数据带入4.7式中得灵敏度系数1.15动作时间保护4的段为零序速断电流保护，故动作时间均为0s,保护4的段为限时零序电流速断，比段延迟一个t,

9、故保护1的段的动作时间为0.5s4.3.1保护4零序段零序段保护按躲开末端最大不平衡电流得： (4.16)将4.16结果带入4.4中得动作电流作为近后备保护 满足要求作为远后备保护 满足要求保护4的段保护与下段线路配合，动作时间比段的动作时间延迟t，故动作时间为1s.第五章 二次展开原理图的绘制绘制保护1、保护4的跳闸图如图5.1,图5.2。图5.1 保护1、保护4跳闸回路第六章 零序保护的评价零序保护的特点：选择性:单电源辐射网络上可保证获得选择性； 多电源网络上在某些特殊情况下才获得选择性。速动性:无时限速断和带时限速断保护动作是迅速的； 定时限过电流保护则常常不能满足速动性的要求 灵敏性

10、:被保护线路很短时，无限时电流速断保护为零。 长距离重负荷线路过电流保护的灵敏度 常常也很小。 灵敏度差是电流电压保护的主要缺点。可靠性:原理简单，逻辑少，整定计算和校验容易。 简单，可靠性好是它的主要优点。零序电流保护通常由多段组成，一般是三段式，并可根椐运行需要增减段数。为了某些运行情况的需要，也可设置两个一段或二段，以改善保护的效果。接地距离保护的一般是二段式，一般都是以测量下序阻抗为基本原理。接地距离保护的保护性能受接地电阻大小的影响很大。当线路配置了接地距离保护时，根椐运行需要一般还应配置阶段式零序电流保护。特别是零序电流保护中最小定值的保护段，它对检测经较大接地电阻的短路故障较为优

11、越。因此，零序电流保护不宜取消，但可适当减少设置的段数。第七章 致谢历经两周的课程设计，今天终于落下帷幕。在此郑重感谢兢兢业业的赵老师一学期的悉心教导，感谢多日来互帮互助的同学们。是你们指引我进步，指导我做好电力系统继电保护课程设计参考文献【1】电力系统继电保护和自动装置设计规范GB50062-922【2】电工设计手册二册【3】电力系统继电保护原理及新技术第二版，李佑光主编，科学出版社（英文版 ） easily blame, to prevent the broken window effect. Supervise the leading cadres to play an exemplar

12、y role, take the lead in the strict implementation of the and , lead to safeguard the solemnity and authority of the party discipline, ensure that the party discipline and the laws and regulations for implementation in place. Throughout the discipline in the daily supervision and management, strengt

13、hen supervision and inspection, from the thorough investigation of violations of discipline behavior. Strengthen to key areas, key departments and key projects as well as the masses reflect the concentration of the units and departments for supervision. - strengthening supervision, discipline inspec

14、tion and supervision of cadres to set an example for compliance with the and is a man must be hexyl, blacksmith needs its own hardware. Discipline inspection organs as the executor of the party discipline, and supervisor of the defenders, for its supervision must be more strictly, discipline inspect

15、ion and supervision of cadres to firmly establish the awareness of Party Constitution, sense of discipline and rules consciousness, politics loyalty, sense obey. Action speak Ji Ordinance to set an example of the regulations of the rule of law, strengthen supervision and accept the supervision of th

16、e firmness and consciousness, do comply with and . To firmly establish the discipline must first be disciplined, the supervisor will be subject to the supervision of concept, and consciously safeguard and implement party compasses party, take the lead in practicing three strict real strict, so loyal

17、, clean, play. To be good at learning, the Constitution and the as morality, politics and brought to fruition; to implement , do not want to, dare not, not with disciplinary ruler to supervision; to discipline a ruler, often the control inspection, and consciously in the ideological red line to draw

18、 the row Ming Good accumulation is indeed the bottom line, so that the heart has fear, said to have quit, the line has ended. Attached: indifferent to heart, calmly to the table in our life, there are many unpredictable things will happen, some good, some bad things, we cannot control is powerless t

19、o stop, but with time, you will find in life sometimes turns out to be not good, some bad things finally turned out to be a good thing, but then we muddy however did not know, this is the life teach us things. 1, life can be complex, can also be simple. Want simple life of precipitation, to have eno

20、ugh time to reflect, to make Become more perfect. Life is the most important thing is not to win, but the struggle; not to have conquered, but to have fought well. 2, the plain is the background of life. Live a plain life, give up on themselves is not a coward, but the wise answers; not disillusione

21、d after the heart, such as ashes, but experience the storm after the enlightenment; not unrewarding perfunctorily, but calm attitude of life of unrestrained self-confidence. Plain living, there is no noise noisy, no earthly troubles, more did not fill in the discontent of desire, some just a calm, a

22、 calm. 3, memory of heart will not good things to erase the, life is a When no movie, pain is a beginning, the struggle is a kind of process, death is a kind of ending. Give up this giving up is the helpless, do not give up the abandoned, do not give up this giving up is ignorance, do not give up sh

23、ould not give up is persistent. 4, a thing figured is heaven, think impassability is hell. Since the living, to live better. Sometimes we because of too narrow-minded, too care around the chores and penny wise and pound foolish, not worth the candle. Some things to attract trouble and worry, complet

24、ely depends on how we look at and deal with it. Dont always take everything back to things, and dont get into a blind alley, dont want to face, dont be narrow-minded. Poke to care, is a kind of open-minded, a free and easy. 5, I am not afraid of others behind me a knife, I afraid to look back and se

25、e stab me, is my intention to treat people; I am not afraid of the truth to tell the best friend, Im afraid he turned to it as a joke to tell dont 6, when we are in a positive frame of mind, you will find many good things; and when we are in a negative state of mind, you will find many depressed thi

26、ngs; life happy and worry, all is you of life attitude, optimistic, good luck; loss of sink, Eritrea company. When you are in adversity, may wish to change a point of view to think everything over to the good Think, because good mentality decided the fate of the! 7, people are tired, rest; heart tir

27、ed, calm. Grow up, mature, this society read. Tired and sad, squat down, to their a hug. Because the world no one can sympathize with you, have mercy on you. You cry, tears is your own; you pain, no one can understand. Then you only tears to smile. 8, each people have youth,Each youth are a story, t

28、he life of the world never gets easier, I want what, wish the world all know, as has been the same; now want anything, for fear that others know, or like to lose the same. 9, the heart move, everything in the world is followed by birth, Rangrang, important thing is often the most difficult to open o

29、nes mouth, because words will reduce its importance; to let strangers people care about your life in the good things, the original is not easy 10, do not blame, do not laugh at who, also dont envy who. Like a person is a kind of feeling, not like a person is true. The truth is easy to explain, I fee

30、l Is unspeakable. The best travel life is that you in a strange place found a long lost touched. 11, happy life not in the bustling in, and in the peace of mind; no matter how many grievances, how uncomfortable, and ultimately to heal themselves or their own, others may got you to comfort, but never

31、 know your heart is how wanjianchuanxin. 12, maam, like a movie, learn to appreciate, learn to be grateful, learn tolerance, and goodness, helping others. Instead of accusing the society, as into one; and an exception is better to give than to what 13, dont envy him A sum of, dont lose your life and

32、 the life, respectively is: the former is a we experienced cannot escape in a day finally will last minute, while the latter is our persistent, we want to cherish the memory of those people and things. 14, learn to smile, learn to strong, the world you know so many people, so many people and you are

33、, you cannot change also cant let everyone like you, so also do not want to do. Life is too short to go crazy to love to go to waste, to chase the dream to regret. 15, when temper, a blessing to go. A wounding elegant people, the key is to control their own emotions. With the mouth is the most stupi

34、d behavior. A control negative emotions than a can take a city more powerful water flow slow, language is expensive. People spent two years of time to learn to speak, but to spend a few years time to shut up. That is a kind of ability, that is a kind of wisdom. 16, life is not perfect, sometimes, gr

35、owth is not a cry, not an eyeful of tears, there is no trace of emotion, there is no gleam of hope, no desire, no action, no static, there is only one kind of downward sinking feeling, sink A murky? 6? 7? 6? 7 sink? 6? 7? 6? 7 toward the bottom of the sink. 17, in some way, do not go, you will not k

36、now the other side scenery is beautiful. To you is not good, you do not mind too much, no one has an obligation to you; you learn knowledge, is you have weapons, you can start from scratch, but not unarmed; how do you treat people, does not represent how others treat you, if cannot see through this

37、point, only inviting worry. 18, time is like a sponge in the water, as long as you are willing to squeeze, the total water is still there. Every life, after the ups and downs The best test of live, to life, survival and continuation, do not stop the struggle in the joys and sorrows of life on the ro

38、ad, so that different soul to bear life beat, acceptance of suffering. 19, indifferent to heart, calmly in table, elegant and comfortable life, do not take what is so important. The pursuit will be disappointed; to be alive, you will have trouble. Life is the most afraid of what all want to care abo

39、ut, but also what all grasp is not firm, without scenery, separated populations, such as not to desire, all docked in the fate of the end. Why is too rigid, the natural, to go stay not to live, let go of obsession, revel is 20, if the fate of the broken Hopes of sailing, please dont despair, the coa

40、st is still, if the fate of the withered petals of the beautiful, please do not sink, the spring is still, life will always be endless trouble, please dont helpless, because they are still alive, is still a dream, the sun still, we still. Lost, keep memories; to get, must work to; but the most impor

41、tant is good to cherish their own. 21, life, select the complex, is to choose the pain; choose a simple, is choose to be happy. The complex world like aSignificance of pride. Hope is the ornate palace, outside people admiring the magnificent, living in the deep knowledge of living it to pay the pric

42、e. Simple world as a simple log cabin outside ridiculed shabby, the heart is willing to go live to know the joy. Suffering and joy is their own choice. 22, learn how to use a single powerful heart, let the past be the past, let the future come. Life is really the end of the end of an eagle is flying

43、 wings, life is constantly pursuit. Dont miss to regret, dont wait for old just miss. Time to return, seize every moment, again painstakingly again tired also Those struggling to fly. 23, life could not Yimapingchuan, even flat pavement, inevitably there will be a few pieces of roadblocks. Some of t

44、he rocks around the past, while others have to move it out. Just move others put the stone is very easy, because the stone from the appearance we can discern; difficult to myself to move away the heart of stone head. Leave time to spend with her, often reflect my heart, so as to remove your heart of

45、 stone. 24, everything does not have to be demanding, come to, everything does not have to care about, over the past; failing to do not frown, laugh it laugh. Results Dont demand, do to; life is a simple, calm and peaceful. Always not to choose their own path and regret, life is like a train, the sc

46、enery and then the United States will retreat, the passage of time and encounter will eventually drifting further and further away, before is always himself. 25, everyone has a weakness, weakness is true humanity. That has no weakness, a shallow person. That people think there is no weakness, mostly false. Life has shortcomings, there are shortcomings is the real life. That no one regret, or