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山東電氣成套:高低壓設備的30條必學知識

發布時間:2025-10-18 來源:http://www.sxxxg.com.cn/ 瀏覽量:

  咱們說的高低壓成套設備啊,簡單來講,就是把一堆高低壓電氣設備提前設計好,組裝調試妥當后湊成的一個整體。在電力系統里,它可是常客,主要用來控制、保護電能,還負責把電能分配到各個地方。這設備對電力系統可太重要了,有了它,電力系統才能穩穩當當運行,供電也更可靠、更。從功能和使用場景來看,高低壓成套設備分好多種類呢。像開關設備,斷路器、負荷開關都在這一類;控制設備里有接觸器、繼電器;保護設備包含熔斷器、過電壓保護器;還有測量設備,比如電壓表、電流表。這些設備就像一個團隊,齊心協力讓電力系統順順利利工作。那高低壓成套設備的基礎知識,哪些是得牢牢掌握的呢?別著急,下面文章都給大家整理好啦,建議大伙趕緊收藏起來慢慢看。1、開關柜為什么叫“成套”?base64_image

  The high and low voltage complete set of equipment we are talking about, in simple terms, is a whole made up of a pile of high and low voltage electrical equipment designed in advance, assembled and debugged properly. In the power system, it is a frequent visitor, mainly used to control and protect electrical energy, and also responsible for distributing electrical energy to various places. This device is extremely important for the power system. With it, the power system can operate stably, and the power supply is more reliable and safe. From the perspective of functionality and usage scenarios, there are many types of high and low voltage complete sets of equipment. Switchgear, circuit breakers, and load switches are all in this category; There are contactors and relays in the control equipment; The protective equipment includes fuses and overvoltage protectors; There are also measuring devices, such as voltmeters and ammeters. These devices are like a team, working together to make the power system work smoothly. What are the key points to firmly grasp the basic knowledge of high and low voltage complete sets of equipment? Don't worry, the following articles have been organized for everyone. I suggest everyone save them and read them slowly. 1. Why is the switchgear called a "complete set"?

  開關柜由進線、計量、PT、出線等組合而成。柜內裝有一次、二次元件,在使用時必須配套,所以叫“成套”。2、我國電力電壓有多少個級別,并說出分級的作用。答:分為500KV、220KV、110KV、35KV、10KV、380V、220V等級別。由于電壓的高低與線損有關,電壓越高、線損越低。因而,電網常采用高壓輸電,輸送電的距離越遠,其電壓級別越高。3、為什么要放電(10KV級別)?用什么方法可以放電?答:在進行停電的時候,為了防止電容還有余電,傷及人員,所以必須卸電壓。的卸電壓的方法:打開柜門或屏板時,不可直接用手接觸母線。先用10KV的試電筆檢查是否有電,然后找一顆導線,一頭接地、一頭接在試電筆前端,用試電筆前端接觸母線放電,完成后方可維修,保證人身。切記這一點。

  The switchgear consists of incoming lines, metering PT、 Composed of combinations such as outgoing lines. The cabinet is equipped with primary and secondary components, which must be matched in use, so it is called "complete set". 2. How many levels of electricity voltage are there in our country, and what is the function of each level. Answer: It is divided into levels such as 500KV, 220KV, 110KV, 35KV, 10KV, 380V, 220V, etc. Due to the correlation between voltage and line loss, the higher the voltage, the lower the line loss. Therefore, the power grid often adopts high-voltage transmission, and the farther the distance of electricity transmission, the higher the voltage level. 3. Why discharge (10KV level)? What methods can be used for safe discharge? Answer: During a power outage, in order to prevent residual electricity in the capacitor from injuring personnel, the voltage must be unloaded. Safe method of voltage discharge: When opening the cabinet door or screen, do not directly touch the busbar with your hands. First, use a 10KV test pen to check if there is electricity, then find a wire with one end grounded and the other end connected to the front end of the test pen. Use the front end of the test pen to contact the busbar for discharge, and only after completion can maintenance be carried out to ensure personal safety. Remember this.

  4、10kV試驗電的電壓應該是多少?國內、國際標準有什么區別?答:國內:柜體42kV,斷口48kV;國際:36kV。

  4. What is the voltage required for a 10kV test circuit? What is the difference between domestic and international standards? Answer: Domestic: Cabinet 42kV, fracture 48kV; International: 36kV.

  5、 泄壓通道的作用是什么?答:若萬一柜體發生爆炸,將會產生一股強勁的氣浪。這時如果柜頂有泄壓通道,則氣浪可由頂部排出,而不影響其他部分的正常工作;若無泄壓通道,氣浪就會向薄弱的地方沖開。6、 開關柜應裝配那些主要一次元件?答:斷路器、避雷器、零序互感器、電流互感器(CT)、電壓互感器(PT)、高壓熔斷器等。

  5. What is the function of the pressure relief channel? Answer: If the cabinet explodes, it will generate a strong gust of air. If there is a pressure relief channel on the top of the cabinet at this time, the air waves can be discharged from the top without affecting the normal operation of other parts; If there is no pressure relief channel, the air waves will rush towards the weakest point. 6. What are the main primary components that should be installed in the switchgear? Answer: Circuit breakers, lightning arresters, zero sequence transformers, current transformers (CT), voltage transformers (PT), high-voltage fuses, etc.

  7、環網開關柜的作用是什么?靠什么保護變壓器?答:作用是可帶負荷分合閘,它靠高壓熔斷器來保護變壓器。

  7. What is the function of a ring network switchgear? What is the protection for transformers? Answer: Its function is to enable load opening and closing, and it relies on high-voltage fuses to protect the transformer.

  8、空氣絕緣距離的標準是多少?答:相間及相對地的空氣距離,10KV要求125mm。

  8. What is the national standard for air insulation distance? Answer: The air distance between phases and relative ground, 10KV requires 125mm.

  9、什么叫絕緣件爬距?答:高壓帶電側地的、沿絕緣件外表爬行的導通距離叫絕緣件爬距。10KV要求235mm。

  9. What is the creepage distance of insulation components? Answer: The conductive distance from the high-voltage live side to the ground and crawling along the surface of the insulation is called the insulation crawling distance. 10KV requires 235mm.

  10、用什么方法檢查真空開關是否真空?答:用耐壓試驗檢測。斷口用48kV檢測。11、隔離開關有什么作用,用于哪種柜類?答:隔離開關用于固定柜。不帶負荷操作,提供明顯斷口,方便維修。

  10. What method is used to check if the vacuum switch is vacuum? Answer: Use a voltage withstand test for testing. The fracture surface is tested with 48kV. 11. What is the function of an isolation switch and which type of cabinet is it used for? Answer: Isolation switches are used to fix cabinets. Operating without load, providing obvious fractures for easy maintenance.

  12、高壓熔斷器作用是什么?答:作保護變壓器用。注:PT屬小型變壓器類。

  12. What is the function of a high-voltage fuse? Answer: Used for protecting transformers. Note: PT belongs to the category of small transformers.

  13、帶電顯示器有什么作用?答:起指示作用,顯示柜內是否有高壓電。

  13. What is the function of a live monitor? Answer: It serves as an indicator to show whether there is high voltage electricity inside the cabinet.

  14、程序鎖起什么作用?答:柜與柜操作順序按規定程序連鎖,起到防誤操作的作用。

  14. What is the function of program lock? Answer: The operation sequence of cabinets is interlocked according to the prescribed procedure, which plays a role in preventing misoperation.

  15、接地開關起什么作用?答:接地開關安裝在出線端,檢修時可以防止倒供高壓電,保證人身。16、活門的作用是什么?答:當手車拉離柜體時,防止人或金屬接觸到帶高壓電的靜觸頭。

  15. What is the function of the grounding switch? Answer: The grounding switch is installed at the output end, which can prevent the reverse supply of high voltage electricity during maintenance and ensure personal safety. 16. What is the function of the valve? Answer: When the handcart is pulled away from the cabinet, prevent people or metal from coming into contact with the high-voltage static contacts.

  17、母線為什么要套膠?答:起到一個絕緣的作用,可減少空氣絕緣距離,防止小動物入柜造成短路事故。

  17. Why do busbars need to be glued? Answer: It plays an insulating role, reducing the distance of air insulation and preventing short circuit accidents caused by small animals entering the cabinet.

  18、避雷器的作用是什么?為什么每組柜都少有一個避雷器?答:避雷器按電壓等級設計,千萬不能裝錯。有些還根據用途不同設計而設計不同。如:發電廠輸出電的、有線路運行的、有電容的、有電站用的。避雷器主要是當線路中某地段產生過高電壓時,可將其吸收以達到線路運行的目的。https://www.dgdqw.com如:進線柜有一套避雷器,可保護柜內線路;而外路電源在進柜時,已經裝有避雷器,所以如果外路電源產生高電壓,由于有避雷器作保護,入柜時就比較;出線柜下端帶避雷器,主要是考慮真空斷路器分合時會產生過電壓現象,所以必須安裝避雷器以代替過電壓吸收器。19、說說電流互感器及零序互感器的作用。答:電流互感器起測量、計量、保護作用;零序互感器起保護作用。

  18. What is the function of lightning arrester? Why does each cabinet have at least one lightning arrester? Answer: Lightning arresters are designed according to voltage levels and must not be installed incorrectly. Some designs also vary depending on their intended use. For example, power plants that output electricity, those that operate on power lines, those that have capacitors, and those that are used in power stations. Lightning arrester is mainly used to absorb high voltage generated in a certain section of the line to achieve safe operation of the line. https://www.dgdqw.com For example, the incoming cabinet has a set of lightning arresters that can protect the safety of the circuits inside the cabinet; When the external power supply enters the cabinet, a lightning arrester is already installed. Therefore, if the external power supply generates high voltage, it is safer to enter the cabinet due to the protection of the lightning arrester; The lower end of the outgoing cabinet is equipped with a lightning arrester, mainly considering the overvoltage phenomenon that may occur when the vacuum circuit breaker is opened and closed. Therefore, a lightning arrester must be installed to replace the overvoltage absorber. 19. Explain the functions of current transformers and zero sequence transformers. Answer: Current transformers serve the functions of measurement, metering, and protection; Zero sequence transformers provide protection.

  20、電流互感器可以返轉裝配嗎?為什么?答:正常流向L1→L2,如果由L2→L1 ,則二次線設計需作修改。21、濕控器起什么作用?答:通過感應探頭探測出濕度,如超過正常濕度,通過發熱板發熱進行調節。有兩種操作方式:自動和手動。

  20. Can current transformers be retrofitted for assembly? Why? Answer: The normal flow direction is L1 → L2. If L2 → L1, the secondary line design needs to be modified. 21. What is the function of the humidity controller? Answer: The humidity is detected through an induction probe. If it exceeds the normal humidity, it is adjusted by heating with a heating plate. There are two operation modes: automatic and manual.

  22、一次方案圖起什么作用?答:代表主回路線路上所裝配的原件及走向

  22. What is the function of a plan diagram? Answer: Represents the components and routing assembled on the main circuit line

  23、PT與CT叫法代表什么?答:PT—電壓互感器,CT—電流互感器

  What do the names PT and CT represent? Answer: PT - Voltage Transformer, CT - Current Transformer

  24、AC與DC叫法代表什么?答:AC—交流電,DC—直流電

  What do the names AC and DC represent? Answer: AC - alternating current, DC - direct current

  25、真空斷路器起什么作用?答:能帶負荷分合閘,靠真空滅弧室(真空泡)滅弧。26、斷路器的分類:答:(1)真空斷路器:利用真空(真空度為100000汞柱以下)作為滅弧介質和主絕緣介質。滅弧的動靜觸頭均密封在真空滅弧室內。主要有10VK、35KV電壓等級。(2)六氟化硫斷路器:問世較晚。七十年代初才被廣泛應用,目前已是電力系統的設備,以SF6氣體作為滅弧介質。切斷能力比一般斷路器高10倍左右。電弧電壓低。燃弧時間短觸頭燒壞少,能頻繁操作。缺點SF6較貴。需要回收裝置,結構較復雜。我國已制造出勤率220KV以SF6為主體的全封閉式組合電器。把斷路器,隔離開關。互感器,避雷器。母線等變電站的主要設備全部裝在交有SF6氣體的密封容器中大大減小了變電站占地空間。是超高壓電器發展主要方向。國外已廣泛應用。(3)斷路器:以壓縮空氣為滅弧介質。在超高壓方面目前是主要產器。我國產380KV。國外已產765KV。(4)自產所斷路器:利用固定介質受電弧作用分解成氣體進行吹弧使電弧熄滅。電壓低斷流小。適用于農業用電子統。(5)磁吹斷路器:利用磁場將電弧吹入滅弧柵中。27、電力變壓器答:變壓器是一種變換電壓(電流)的電氣設備。它不能變換功率。基本結構:主要由一個閉合鐵芯和繞在鐵芯上兩個匝數不同并互相絕緣的線圈(即繞組)組成,為了減小渦流及磁滯損失,鐵芯是用涂有絕緣漆,厚度為0.35-0.5mm導磁性能很好的硅鋼片疊成,它組成變壓器中的閉合磁路一次線圈稱厚線圈式原邊,二次線圈稱付線圈式付邊,用三分單相變壓器連接成的三相變壓器組,就是三相變壓器。28、電流互感器答:基本結構和普通電壓器一樣,也是由一次繞組、鐵芯和二次繞組組成,使用時,一次側與被測電路負荷串聯,二次側串接5A的電流表和保護電路,一次側用粗導線,其匝數只有一匝或幾匝,二次側導線很細,匝數很多。根據變壓器運行原理:電流互感器一次側與二次側電流之比應與一二次側匝數之比成反比:IN1/IN2=N2/N1,(IIN1、IN2分別為一次側、二次側電流,N1、N2分別為一次側、二次側線圈匝數)。

  What is the function of a vacuum circuit breaker? Answer: It can open and close with load and extinguish the arc through a vacuum arc extinguishing chamber (vacuum bubble). 26. Classification of circuit breakers: Answer: (1) Vacuum circuit breaker: uses vacuum (vacuum degree below 100000 mercury) as the arc extinguishing medium and main insulation medium. The dynamic and static contacts for arc extinguishing are sealed inside the vacuum arc extinguishing chamber. There are mainly voltage levels of 10VK and 35KV. (2) Sulfur hexafluoride circuit breaker: came out relatively late. It was not widely used until the early 1970s and is now an advanced equipment in the power system, using SF6 gas as the arc extinguishing medium. The cutting ability is about 10 times higher than that of a typical circuit breaker. The arc voltage is low. Short arc time, less contact burnout, and frequent operation. Disadvantages: SF6 is relatively expensive. We need a recycling device with a complex structure. China has manufactured fully enclosed composite electrical appliances with SF6 as the main component, with an attendance rate of 220KV. Turn on the circuit breaker and isolation switch. Transformer, lightning arrester. The main equipment of the busbar and other substations are all installed in sealed containers with SF6 gas, greatly reducing the footprint of the substation. It is the main direction of development for ultra-high voltage electrical appliances. It has been widely used abroad. (3) Circuit breaker: using compressed air as the arc extinguishing medium. Currently, it is the main producer in the field of ultra-high voltage. Our country produces 380KV. 765KV has been produced abroad. (4) self-produced circuit breakers: use a fixed medium to decompose into gas under the action of an arc and blow the arc to extinguish the arc. Low voltage leads to small interruption. Suitable for agricultural electronic systems. (5) Magnetic blow circuit breaker: uses a magnetic field to blow an arc into the arc extinguishing grid. 27. Power Transformer Answer: A transformer is an electrical device that converts voltage (current). It cannot change power. Basic structure: It mainly consists of a closed iron core and two coils (i.e. windings) with different turns wound on the iron core and insulated from each other. In order to reduce eddy current and hysteresis losses, the iron core is made of silicon steel sheets coated with insulating paint and with a thickness of 0.35-0.5mm and good magnetic conductivity. It forms the closed magnetic circuit of the transformer. The primary coil is called the thick coil type primary side, and the secondary coil is called the auxiliary coil type auxiliary side. The three-phase transformer group is composed of three single-phase transformers connected together, which is the three-phase transformer. 28. Current Transformer Answer: The basic structure is the same as that of a regular voltage transformer, consisting of a primary winding, an iron core, and a secondary winding. When in use, the primary side is connected in series with the load of the tested circuit, and the secondary side is connected in series with a 5A ammeter and protection circuit. The primary side uses a thick wire with only one or a few turns, while the secondary side wire is very thin with many turns. According to the operating principle of transformers, the ratio of the current on the primary and secondary sides of a current transformer should be inversely proportional to the ratio of the number of turns on the primary and secondary sides: IN1/IN2=N2/N1, where IIN1 and IN2 represent the currents on the primary and secondary sides, and N1 and N2 represent the number of turns on the primary and secondary coils, respectively.

  29、電壓互感器答:基本結構:是擴大電壓量程的特殊變壓器,基本結構和普通變壓器相同。故電壓互感器一二次側的電壓比U1/U2=N1/N2(N1、N2分別為一二次側線圈匝數)。

  29. Voltage Transformer Answer: Basic Structure: It is a special transformer that expands the voltage range, and its basic structure is the same as that of a regular transformer. Therefore, the voltage ratio of the primary and secondary sides of the voltage transformer is U1/U2=N1/N2 (N1 and N2 are the turns of the primary and secondary coils, respectively).

  30、高壓絕緣子答:高壓絕緣子作用:用來支持和固定母線與帶電導體,并使帶電導體間或導體與大地之間,有足夠的距離和絕緣;絕緣子絕緣是靠表面形狀來獲得。不同電壓等級的絕緣子。除具有不同的有效高度外。其表面情況也不一樣。其表面做成高低凹凸的裙邊,以增加其表面長度。

  30. High voltage insulator Answer: The function of high voltage insulators is to support and fix busbars and live conductors, and to provide sufficient distance and insulation between live conductors or between conductors and the ground; Insulation of insulators is obtained by surface shape. Insulators of different voltage levels. Except for having different effective heights. Its surface condition is also different. Its surface is made into a high-low concave convex skirt edge to increase its surface length.

  本文由  山東電氣成套 友情奉獻.更多有關的知識請點擊  http://www.sxxxg.com.cn/   真誠的態度.為您提供為的服務.更多有關的知識我們將會陸續向大家奉獻.敬請期待.

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