中壓電網(wǎng)接地方式翻譯-中英對(duì)照
摘 要
中壓電網(wǎng)中性點(diǎn)接地方式的選擇是一個(gè)綜合性的技術(shù)問(wèn)題，它涉及到供電可靠性、人身及設(shè)備安全、絕緣、過(guò)電壓、繼電保護(hù)、通信（電磁環(huán)境）、接地裝置等各個(gè)方面。它具有
理論研究與實(shí)際經(jīng)驗(yàn)密切結(jié)合的特點(diǎn)，是電力系統(tǒng)實(shí)現(xiàn)安全與經(jīng)濟(jì)運(yùn)行的技術(shù)基礎(chǔ)和系統(tǒng)工程。
論文介紹了我國(guó)6~66kV中壓電網(wǎng)中性點(diǎn)主要的接地方式及其各自的優(yōu)缺點(diǎn)，論述了一種應(yīng)用于中性點(diǎn)不接地系統(tǒng)消除單相接地故障及選線、消除鐵磁性諧振的新方法以及實(shí)現(xiàn)這種方法的智能綜合保護(hù)裝置。
論文的主要?jiǎng)?chuàng)新之處：1）采用新的電壓消弧法：用電抗器鉗制故障相的電壓，有效地防止接地電弧的重燃，消除弧光接地過(guò)電壓，保證供電可靠性；2）歸納不接地系統(tǒng)單相接地故障的規(guī)律，確立其接地電阻與相電壓、中性點(diǎn)位移電壓關(guān)系的數(shù)學(xué)模型，提出判斷故障相的依據(jù)、創(chuàng)造性地設(shè)計(jì)了相應(yīng)的判斷和保護(hù)程序，不論接地電阻值如何變化，都能夠準(zhǔn)
確對(duì)高阻接地故障提供有效的保護(hù)，將以往難以察覺(jué)故障消滅在萌芽狀態(tài)。3）采用新的消諧方法：當(dāng)諧振發(fā)生時(shí)，直接在一相母線與地之間并接電抗器，使回路遠(yuǎn)離諧振點(diǎn)，并限制諧振過(guò)電壓。
論文所述的保護(hù)裝置通過(guò)了國(guó)家相關(guān)檢驗(yàn)機(jī)構(gòu)的全面、嚴(yán)格的電氣性能和環(huán)境型式試驗(yàn)、電磁兼容試驗(yàn)、10kV電網(wǎng)的現(xiàn)場(chǎng)接地故障試驗(yàn)、并在多個(gè)變電站10kV電網(wǎng)系統(tǒng)掛網(wǎng)運(yùn)行等，證實(shí)了這種新方法及裝置的可靠性與實(shí)用性。該裝置已獲國(guó)家級(jí)新產(chǎn)品鑒定, 鑒定結(jié)論為：“裝置的設(shè)計(jì)思路新穎，保護(hù)性能良好，其消弧、消諧的方法、對(duì)高阻接地故障的判別和保護(hù)處于國(guó)內(nèi)領(lǐng)先水平”。
關(guān)鍵詞：中性點(diǎn)接地方式、弧光接地 高阻接地 選線 鐵磁諧振 智能綜合保護(hù)裝置
Neutral-poin grounding mode in medium voltage network
and Technique to eliminate single-phase ground fault
Abstract
It is comprehensive technological issue for medium voltage network to choose its neutral-point grounding mode. This issue will involve reliability of power supply; the safety of person and equipment; insulation; overvoltage; protective relay; communication (mangnetic environment); earthing device and so on. It has characteristic of combining theory with practice, meanwhile it is also technological basis and system engineering for power system to operate economically and safely.
This paper introduces main neutral-point grounding modes in 6-66KV medium voltage network in our country and its advantages and disadvantages in some cases.
And present a kind of new method of eliminating single-phase ground fault; ferro-resonance and checking up line troubled in neutral-point non-ground system.
At same time ,in this paper also describe a comprehensive intelligence device that implements these techniques.
The major innovation in this paper includes:1) developing a new voltage method that eliminates electric arc by a reactor that limit overvoltage between faulty phase and the ground. This reactor can effectually prevent electric arc from reigniting; and eliminate arc-grounding overvoltage in order to accomplish reliability of power supply.2) find a single-phase faulty rules in non-grounded system and a mathematical mode that relate to relationship between earthing resistance and phase voltage, neutral-point displacement voltage. As a result, we got a criterion that can judge faulty phase, according to this criterion we design protective program that can effectually protect network from high-resistance ground faulty(HRGF)no matter how resistance change, as a
result we can destroy the single-phase faulty while it just right form..3)using a new method to suppress resonance: when resonance just happened, directly adding a reactor in parallel between a phase bus and ground in order to apart circuit from resonance point so as to limit resonance overvoltage.
Our protective device as described above has passed a series of tests conducted by relevant government inspection agencies. These tests include an extensive and rigorous electrical performance test; an environmental type test; an electromagnetic compatibility test; and operation in many 10KV substations. This new technique and protective device are shown to be reliable and practical. A national-level new product appraisal was completed and a certification was granted.
It is stated in the certificate that:” the design of this device is new style, protective performance good, the method for eliminating electric are, resonance; criterion and protection identifying HRGF are first class in China.”
Key words: neutral-point grounding mode, electric arc grounding, high-resistance grounding, checking up line faulty, Ferro-resonance, comprehensive intelligence protective device
①發(fā)生單相接地故障時(shí)（例如A相），故障相的對(duì)地電容C0被短接；
①When the single-phase earth trouble occurs (such as A phase), earth capacitance C0of fault phase is shorted;
②非故障線路3I01的大小等于本線路的接地電容電流，其電容性無(wú)功功率的方向?yàn)橛赡妇�流向線路；
②The size of non-fault line 3I01 is equal to the earth capacitive current of this line. The direction of inactive power of the capacitive character is to flow to the line from the bus bar;
③故障線路3I02的大小等于所有非故障線路的3I01之和，也就是所有非故障線路的接地電容電流之和；其電容性無(wú)功功率的方向?yàn)橛删�路流向母線；
③The size of non-fault line 3I02 is equal to the sum of all non-fault line 3I01, that is to say the sum of the earth capacitive current of all non-fault line; the direction of inactive power of the capacitive character is to flow to the line from the bus bar;
④若零序電流互感器的極性是以變電所母線流向線路為正方向，那么非故障線路的零序電流超前零序電壓90°，故障線路的零序電流滯后零序電壓90°，故障線路的零序電流與非
故障線路的零序電流在相位上相差180°。
④If the polarity of the mutual inductor of zero sequence current calculates the positive direction by the flowing direction of the bus bar of transformer station, the advanced zero sequence voltage of zero sequence of non-fault line is about 90°. The delayed zero sequence current of zero sequence of fault line is about 90°. The phase difference of the phrase of the zero sequence of fault line and zero sequence of non-fault line is about 180°.
2013.4.23