變壓器保護的英文文獻范文

　　篇一：變壓器英文文獻

　　Transformer short-circuit accident on the handling of Thoughts Astract: The accident in the transformer, the higher probability, a greater threat to the device is the transformer short circuit, especially the low pressure side of the transformer short-circuit. Transformer low voltage side to the incident after short inspection and processing to be described.

　　Key words: Thinking transformer short-circuit accident

　　Treatment transformer short-circuit accident, first by checking, testing to find out the real problem lies; followed the process should also pay attention to related issues. Specific considerations are as follows:

　　First, the transformer short-circuit accident inspection, testing.

　　When subjected to sudden short-circuit transformers, high and low pressure side will be significant short-circuit current, no time off in a very short time circuit breaker, short circuit currents and current proportional to the square of the electric power to act on the transformer winding, This electric power can be divided into radial force and axial force. In short, the effect of radiation on the winding force of tension will be high voltage winding, low voltage winding

　　under pressure. Since winding round, round objects, the pressure ratio is more easily deformed by tension, therefore, more low-voltage winding deformation. Sudden short circuit in the axial force generated by the compression and the high and low voltage winding winding because the axial displacement, axial force is also acting on the core and clamps.

　　Therefore, in face of sudden short-circuit the transformer, the most prone to deformation of the low-voltage winding and balanced winding, then the high voltage windings, core and clamps. Therefore, the transformer short-circuit accident, the inspection is to check the main winding, core, clamps and other parts.

　　First, the winding of the inspection and test

　　When the transformer short-circuit in the electric power under the action of winding the same time by pressing, pulling, bending and other forces acting, concealment caused by the failure of its strong, is not easy to check and repair, so the short circuit fault should focus on checking winding situation.

　　(A) of the transformer DC resistance measurement

　　According to the transformer DC resistance measurements to check the

　　winding DC resistance unbalance and compared with previous measurements, can effectively examine the transformer winding damage. For example, a low voltage transformer short-circuit side after the accident to the DC resistance of

　　C increased by about 10% of new shares which may be winding to determine the situation, and finally winding hanging out, it was discovered off one phase winding C shares.

　　(2) measurement of transformer winding capacitance.

　　By the winding capacitance between the windings, and the cake layer

　　capacitance and the winding-fat capacitor. This capacitor and the winding and core and in the gap, winding and core of the gap between the windings, the gap between cake layers and on. When the winding deformation, the general was "S"-shaped bend, which leads to winding on the core of the gap distance smaller, winding capacitance to ground will be larger, but the smaller the gap, the greater the capacitance changes, so winding electrical capacity can indirectly reflect the degree of winding deformation.

　　(3) check after hanging hood.

　　After lifting the transformer cover, check out the transformer if internal molten slag or copper slag or aluminum pieces of paper, high-density cable, you can determine the occurrence of a greater degree of winding deformation and off shares, etc. In addition, the shift from the winding Pad or off, clips and other bits, the pressure screw displacement can also determine the extent of the damage the windings.

　　2, core and clamps checks.

　　Transformer core should have sufficient mechanical strength. Core of the mechanical strength is by all clamping on the core strength of their

　　connections to guarantee. When the electric power generated when the winding, winding clamping axial force of the reaction will be offset, if the clamps, pull strength of less than the axial force plate when the clamps, pull board and the winding will be damaged. Therefore, we should carefully check the core, clamps, pull the state board and its connections.

　　(1) Check the yoke iron core chips have ran up and down situation.

　　(2) should be measured through the core and the core of the insulation

　　resistance of the screw, check whether the damaged wearing coat-core screw; check the drawing board, drawing board connector for damage.

　　(3) because of short circuit in the transformer, the plate and the clamps may

　　occur between the displacement pressure of the nail plate and the yoke pulled off the ground connection, or over-current chip burning, so the plate for the winding, in addition to check the pressure screw, plate damaged, we must also check the winding and the pressure on the yoke screw and the ground connection is reliable.

　　3, the analysis of transformer oil and gas.

　　After suffering the impact of transformer short-circuit in the gas relay large amounts of gas may accumulate, it can be taken after the accident in the transformer gas relay the gas and oil inside the transformer for laboratory analysis, to determine the nature of the incident.

　　Second, the transformer short-circuit fault handling precautions.

　　1, pieces of insulation should be replaced to ensure the performance of insulators.

　　When dealing with the replacement of insulation parts should be tested for performance, and meet the requirements before use. In particular insulation on the lead frame wood attention should be paid. Wood should be placed before installation of about 80 ℃ hot transformer oil immersion period of time to ensure that the insulation of wood.

　　2, transformer oil filling the transformer insulation test should be conducted after 24 hours of rest.

　　Because some of the moisture in the insulation pieces soak in the hot oil a longer time, the water will spread to the surface of insulation, if the fuel

　　injection after the test check the insulation defects often do not come out. For example, a 31.5MVA the 110kV transformer low voltage side of the

　　replacement of the treatment of a stent kV copper block, transformer filling of all the normal tests, 10kV low voltage side of the core, clamps, and insulation resistance is reduced to about 1MΩ. Cover by hanging after examination, found that the stent 10kV copper block insulation is very low. Therefore, the transformer insulation test should be conducted 24 hours after the grease still more reliable.

　　3, the core back to the equipment should be noted that the sharp corners.

　　Installed in the back yoke, attention should be angular core chip, and timely measurement of oil duct insulation, in particular, pay attention to the oil channel at the chip corners, to prevent overlap resulting core chip multi-point grounding. For example, one of the 220kV 120MVA transformers, replacement

　　of the low pressure side of the winding back yoke installed, due to back loaded in the chip did not pay attention to sharp corners, and no timely measure the oil duct insulation, after installation of insulation to measure the oil channel 0

　　Finally, take a long time to find the core chip, due to short circuit the oil channel sharp corners.

　　關(guān)于處理變壓器短路事故的幾點思考

　　摘要：在變壓器事故中，發(fā)生概率較高、對設(shè)備威脅較大的就是變壓器短路事故，特別是變壓器低壓側(cè)發(fā)生短路，關(guān)于變壓器保護的2000字英語文獻。就變壓器低壓側(cè)短路后進行的事故檢查和處理予以闡述。

　　關(guān)鍵詞：變壓器短路 事故 思考

　　處理變壓器短路事故，首先要通過檢查、試驗找出問題實質(zhì)所在；其次處理過程還應(yīng)注意相關(guān)問題。具體思考如下：

　　首先，變壓器短路事故后的檢查、試驗。

　　變壓器在遭受突發(fā)短路時，高低壓側(cè)都將受很大的短路電流，在斷路器來不及斷開的很短時間內(nèi)，短路電流產(chǎn)生與電流平方成正比的電動力將作用于變壓器的繞組，此電動力可分為輻向力和軸向力。在短路時，作用在繞組上的輻向力將使高壓繞組受到張力，低壓繞組受到壓力。由于繞組為圓形，圓形物體受壓力比受張力更容易變形，因此，低壓繞組更易變形。在突發(fā)短路時產(chǎn)生的軸向力使繞組壓縮和使高低壓繞組發(fā)生軸向位移，軸向力也作用于鐵芯和夾件。

　　因此，變壓器在遭受突發(fā)短路時，最容易發(fā)生變形的是低壓繞組和平衡繞組，然后是高中壓繞組、鐵芯和夾件。因此，變壓器短路事故后的檢查主要是檢查繞組、鐵芯、夾件以及其它部位。

　　一、繞組的檢查與試驗

　　由于變壓器短路時，在電動力作用下，繞組同時受到壓、拉、彎曲等多種力的作用，其造成的故障隱蔽性較強，也是不容易檢查和修復(fù)的，所以短路故障后應(yīng)重點檢查繞組情況。

　�。ㄒ唬┳儔浩髦绷麟娮璧腵測量

　　根據(jù)變壓器直流電阻的測量值來檢查繞組的直流電阻不平衡率及與以往測量值相比較，能有效地考察變壓器繞組受損情況。例如，某臺變壓器短路事故后低壓側(cè)C向直流電阻

　　增加了約10％，由此判斷繞組可能有新股情況，最后將繞組吊出檢查，發(fā)現(xiàn)C相繞組斷1股。

　�。�2）變壓器繞組電容量的測量。

　　繞組的電容由繞組匝間、層間及餅間電容和繞組發(fā)電容構(gòu)成。此電容和繞組與鐵芯及地的間隙、繞組與鐵芯的間隙、繞組匝間、層間及餅間間隙有關(guān)。當繞組變形時，一般呈“S”形的彎曲，這就導(dǎo)致繞組對鐵芯的間隙距離變小，繞組對地的電容量將變大，而且間隙越小，電容量變化越大，因此繞組的電容量可以間接地反映繞組的變形程度。

　　（3）吊罩后的檢查。

　　變壓器吊罩后，如果檢查出變壓器內(nèi)部有熔化的銅渣或鋁渣或高密度電纜紙的碎片，則可以判斷繞組發(fā)生了較大程度的變形和斷股等，另外，從繞組墊塊移位或脫落、壓板等位、壓釘位移等也可以判斷繞組的受損程度。

　　2、鐵芯與夾件的檢查。

　　變壓器的鐵芯應(yīng)具有足夠的機械強度。鐵芯的機械強度是靠鐵芯上的所有夾緊件的強度及其連接件來保證的。當繞組產(chǎn)生電動力時，繞組的軸向力將被夾件的反作用力抵消，如果夾件、拉板的強度小于軸向力時，夾件、拉板和繞組將受到損壞。因此，應(yīng)仔細檢查鐵芯、夾件、拉板及其連接件的狀況。

　�。�1）檢查鐵芯上鐵軛芯片是否有上下竄動情況。

　�。�2）應(yīng)測量穿芯螺桿與鐵芯的絕緣電阻，檢查穿芯螺桿外套是否受損；檢查拉板、拉板連接件是否損壞。

　�。�3）因為在變壓器短路時，壓板與夾件之間可能發(fā)生位移，使壓板與壓釘上鐵軛的接地連接片拉斷或過電流燒損，所以對于繞組壓板，除了檢查壓釘、壓板的受損外，還應(yīng)檢查繞組與壓釘及上鐵軛的接地連接是否可靠。

　　3、變壓器油及氣體的分析。

　　變壓器遭受短路沖擊后，在氣體繼電器內(nèi)可能會積聚大量氣體，因此在變壓器事故后可以取氣體繼電器內(nèi)的氣體和對變壓器內(nèi)部的油進行化驗分析，即可判斷事故的性質(zhì)。

　　其次，變壓器短路故障處理中應(yīng)注意的事項。

　　1、更換絕緣件時應(yīng)保證絕緣件的性能。

　　篇二：關(guān)于變壓器英文文獻

　　Transformer short-circuit fault handling precautions. 1, pieces of insulation should be replaced to ensure the performance of insulators. When dealing with the replacement of the insulation pieces should be tested for performance, and meet the requirements before use. In particular insulation on the lead frame wood attention should be paid. Wood should be placed before installation of about 80 ℃ hot transformer oil immersion period of time to ensure that the insulation of wood.2, transformer oil filling the transformer insulation test should be conducted after 24 hours of rest. Because some of the moisture in the insulation pieces soak in the hot oil a longer time, the water will spread to the surface of insulation, if the fuel injection after the test check the insulation defects often do not come out. For example, a 31.5MVA the 110kV transformer low voltage side of the replacement of the treatment of a stent kV copper block, transformer filling of all the normal tests, 10kV low voltage side of the core, clamps, and insulation resistance is reduced to about 1M . Cover by hanging after examination, found that the stent 10kV copper block insulation is very low. Therefore, the transformer insulation test should be conducted 24 hours after the grease still more reliable.3, the core back to the equipment should be noted that the sharp corners. Installed in the back yoke, attention should be angular core chip, and timely measurement of oil duct insulation, in particular, pay attention to the oil channel at the chip corners, to prevent overlap resulting core chip multi-point grounding. For example, one of the 220kV 120MVA transformers, replacement of the low pressure side of the winding back yoke installed, due to back loaded in the chip did not pay attention to sharp corners, and no timely measure the oil duct insulation, after installation of insulation to measure the oil channel 0 Finally, take a long time to find the core chip, due to short circuit the oil channel sharp corners.變壓器短路故障處理中應(yīng)注意的事項： 1、更換絕緣件時應(yīng)保證絕緣件的性能。 處理時對所更換的`絕緣件應(yīng)測試其性能，且符合要求方可使用。特別對引線支架木塊 的絕緣應(yīng)引起重視。木塊在安裝前應(yīng)置于 80℃左右的熱變壓器油中浸漬一段時間，以保證 木塊的絕緣。 2、變壓器絕緣測試應(yīng)在變壓器注油靜止 24 小時后進行。 由于某些受潮的絕緣件在熱油浸泡較長時間后，水分會擴散到絕緣的表面，如果注油 后就試驗往往絕緣缺陷檢查不出來。 例如一臺 31.5MVA 的 110kV 變壓器低壓側(cè)在處理時更換 了 kV 銅排的一塊支架木塊，變壓器注油后試驗一切正常，10kV 低壓側(cè)對鐵芯、夾件及地絕 緣電阻減小為約 1MΩ。后經(jīng)吊罩檢查，發(fā)現(xiàn) 10kV 銅排的支架木塊絕緣非常低。因此絕緣測 試應(yīng)在變壓器注油靜止 24 小時后進行較為可靠。 3、鐵芯回裝應(yīng)注

　　意其尖角。 在回裝上鐵軛時，應(yīng)注意鐵芯芯片的尖角，并及時測量油道間絕緣，特別是要注意油 道處的芯片尖角，要防止芯片搭接造成鐵芯多點接地。例如一臺 120MVA 的 220kV 變壓器， 在低壓側(cè)更換繞組回裝上鐵軛時， 由于在回裝時沒有注意芯片尖角， 又沒有及時測量油道間 絕緣，安裝完畢后測量油道間絕緣為 0，最后花費了較長時間才找到是由于鐵芯芯片尖角短 接了油道。

　　篇三：變壓器英文論文

　　Substation system over-voltage protection technology

　　Second substation equipment over-voltage protection on electronic information system for the protection of core equipment for the construction of a protected both pressure and other potential system, and through all levels of over-voltage surge protectors of the current step by step into the land of China, Substation secondary safety equipment and reliable operation.

　　1 second over-voltage substation protection

　　In recent years, the substation communications, communications systems, protection systems, background management module frequent over-voltage damage, the main reason for this is weak and its related systems products over-voltage protection level is weak, or no guard against over-voltage Technical measures, the consequences for the safe operation of power grids bring about a greater negative impact. With integrated automation systems and automation systems such as communication systems in the substation weak secondary by the wider use of such electronic systems (equipment) components of the integrated more and more, the growing volume of information storage, speed and accuracy of the Increased and operates only a few volts, current information only microamp level, thus extremely sensitive to outside interference, especially the lightning and electromagnetic pulse, such as over-voltage tolerance is low. When thunder and lightning, such as over-voltage and accompanied by the electromagnetic fields reach a certain threshold, ranging from system failure caused, resulted in heavy equipment or permanent damage to its components. Despite the thunder and lightning viewpoint of electronic systems (equipment) is unlikely, but lightning strike near the land, buildings, communication and air supply line directly Leiyun discharge form, or because of electrostatic induction and the impact of electromagnetic induction formation of over-voltage, There might be connected to the power lines, signal lines or grounding system, through various interfaces to transfer, coupling, radiation and other forms of invasive electronic system (equipment) and lead to serious disturbances or incidents. Therefore, strengthening and improving the electronic system (equipment) protection, to minimize the impact of interference by lightning and other damage caused direct losses and indirect losses, has become the urgent need to solve the problem. 2 over-voltage protection design

　　IEC (International Electrotechnical Commission) TC/81 mine technical committee will be divided into internal and external mine mine in two parts, the external mine is lightning rod (or with lightning, lightning network), Yin Xiaxian and grounding system, Objects to be protected from direct lightning strikes, mine is to prevent internal lightning and other internal over-voltage damage caused by invasive equipment. A comprehensive mine and over-voltage protection systems must be

　　integrated use of discharge (segregation), both pressure (and other potential), shielding (isolation), grounded, limit pressure (clamp) protection, and other technology, in accordance with the external mine And the principle of internal mine, in accordance with the targets of protective features, flexible application to take concrete measures, constitute a complete protection system. Over-voltage substation in the form are: Lightning over-voltage, the resonant frequency over-voltage and over-voltage, over-voltage operation, these over-voltage transmission or electromagnetic induction to the way the lines and equipment on a dangerous over-voltage, in particular, Lightning over-voltage, lightning substation, in the low-voltage power supply system and weak system to produce a strong over-voltage sensor, while the substation to potential rise (for example: the substation grounding resistance to 1 Q, lightning current 10 kA, while the potential for 10 kV), due to the increased potential of the counter lines and equipment damaged lines and equipment and the events have occurred, therefore, despite the substation outside the mine system (lightning rod. Yin Xiaxian And grounding devices) in line with national standards and the requirements of Buban, and the integrated automation and communications automation systems, such as weak secondary have been taken, such as shielding, grounding, isolation, filtering, and other measures, but it can not completely avoid over-voltage powerful lightning And voltage of the system counter the disruption caused damage and, therefore, the second weak system substation and a mine-voltage must also take the appropriate protective measures, in accordance with the IEC within the mine area EMP, the device's power cord, signal Lines, data lines, and the installation of lightning protection and internal over-voltage devices to prevent lightning sensors, channeling people along the lightning current, voltage counterattack, such as transient voltage surge too transient over-voltage caused by a fault and damaged electronic equipment. Over-voltage surge protection in accordance with its connection mode is divided into two series and parallel, the use of over-voltage surge protection tandem with, there may exist because of signal transmission does not match the causes of transmission of the signal interference, in particular data Communication Interface in the series were over-voltage surge protection in place, will have the normal data communications. Therefore, the data communications access I: I in the series were over-voltage surge protection in place, the transmission of data must be carried out conscientiously check if the data are not normal transmission, it may be due to the reasons do not match the transmission signal Interference, should be replaced to match the over-voltage surge protection for. If the use of over-voltage surge protection for use of parallel, the situation is basically non-existent, but the connection mode of over-voltage surge protection for higher technical requirements.

　　3 secondary system over-voltage substation protection

　　3.1 points over-voltage electricity system protection

　　Substation installed in the communications dispatch automation systems are used AC power or a DC power supply equipment for the rectification of its links are generally larger capacity filter capacitance, the transient over-voltage shock absorption of a certain extent, the station Low-voltage transformer side go to feed between the screen using a shielded cable and equipment have a good grounding, the use of modern technology to analyze mine, we must increase the circuit's segregation measures, because its grounding, protection and other electrical grounding all Grounding devices using the same equipment, and equipment are in a LPZOB, the relative strength of strong electromagnetic pulse, the station changed to prevent low-pressure side although there are lines intrusive wave arrester, but the residual pressure high, in the substation of lightning, through the line Coupling and the potential rise caused by over-voltage counterattack still exist, and high-pressure side of the residual pressure as high as several thousand volts, it is necessary to these scheduling automation equipment for the power supply over-voltage circuit protection. Lightning Protection in accordance with the principle of regional division, substation equipment in the secondary power supply system over-voltage sensors lightning protection may be two (B, C level) for the protection of segregation. B-mine use is generally greater flow capacity of the mine installations, the Lightning could be more casual Liuxie people, to achieve the objective of current limit, over-voltage at the same time will reduce to a certain extent, c-mine use With lower residual pressure of the mine installations, you can loop in the remaining scattered lightning Liuxie people, to limit the purpose of over-voltage, over-voltage equipment can be reduced to the level of tolerance. The main power supply system is inhibited lightning protection and operation of the power back to the road and over-voltage surge. According to the substation status of the substation of the second mine-sensing system and the operation and use of two over-voltage protection. As build more substations in the region more open, relatively strong electromagnetic strength, power lines and communication cables are very vulnerable to lightning attacks sensors, sensors along the over-voltage power lines and communication lines into one device, which will damage equipment, Therefore, the exchange of first-class bus to install the power protection (B level) is to ensure the safety of the entire control room, and 80 percent of the over-voltage China, scattered to the earth, play a primary role in the protection, but are still in the exchange of feeder Some of the B-level power supply voltage and mine the residual pressure increases on-line and must therefore be important in the exchange of feeder lines (DC charging screen, UPS, etc.) c-level power protection, which would curb over-voltage electrical equipment to back-end To the level of tolerance.

　　Protective location: It is 1 EC1312 (LEMP protection "in the region of lightning protection principles. Arrester installation should be in different locations at the junction of protected areas, this network, the first-class protection should be located in the bus exchange. In Two on the bus with the installation of a B-class models of a three-phase power supply voltage surge protector.

　　Install Location: AC bus (cabinet).

　　3.1.2 second-class protection measures to deal with

　　For the more important feeder lines on the exchange of equipment, here for the DC charge screen, the installation of c-level three-phase power arrester. As DC charging screen is two-way exchange of electricity supply, so the screen in the DC charge with the installation of two models of c-level three-phase power supply over-voltage surge protector. Installation location should choose the DC charge screen open exchange of air power

　　Commissioner Office.

　　3.2 integrated automation system over-voltage protection

　　Protective position: Computer-based integrated automation system's ability to bear a very low voltage, several hundred volts of over-voltage is enough to damage the equipment, so must the high side arrester the residual pressure (thousands of volts) to further curb to meet equipment Insulation level of need, and because of the potential rise to power and the induction loop is also over-voltage line up on KV, to be used in the exchange of integrated automation system to the exchange on the c-level single-phase installation of a surge Voltage protection. Location should choose to install automated-ping in the Composite Air switch the AC power.

　　3.3 did not ask off power supplies (UPS) over-voltage protection

　　Protection here: because of the internal computer systems, hubs, monitoring equipment, electric energy billing systems and so on through the UPS power supply protection, in order to protect the safety of these micro-electronics equipment, the UPS power supply device in front of the installation of a c-Surge Voltage protection. Optional models: The (UPS for single-phase power input) C-class single-phase power surge or over-voltage protection (UPS for the three-phase power input) of c-level three-phase power supply over-voltage surge protector. Installation should choose the location of UPS into the front line.

　　3.4 communication interface over-voltage protection

　　Communication Interface over-voltage protection compared with the grid supply system, this over-voltage circuit on the degree of sensitivity is much higher, and these are over-voltage equipment in the circumstances it is very fragile. Equipment insulation tolerance level is very low. With the equipment connected to a signal line, data lines, measurement and control lines, and these are basically in line LPZOB

　　region, but also through the LVZOA region, on the lines of sensors over-voltage relatively strong, according to the IEC test, when the electromagnetic field Strength increased to 0.07 GS, will have a micro-computer equipment malfunction, loss of data. And the safety of these circuits is directly related to a system of safety equipment, so important to be on the interface circuit over-voltage protection.

　　3.4.1 remote computer interface devices over-voltage protection

　　Protective position: As substation computer remote installations scattered distribution structure. From remote modules, intelligent telemetry module, intelligent remote control module, intelligent remote-module. The modules are installed in different automated-ping, through the RS232 interface between the modules or field bus communication. These interfaces are in the indoor circuit, equipment interface circuits shorter the distance, so there will be no more sensors to the over-voltage, but the automation equipment and other secondary equipment (measurement unit, computer, etc.) have electrical connections, when Other secondary equipment sensors to a strong over-voltage sensors, will be counter to these automation equipment, communications interface, so that damage to equipment interface circuits, it is necessary in these devices RS232 interfaces on the installation of a surge Voltage protection. Installation location should choose the remote computer interface devices, communications lines.

　　3.4.2 electric energy billing system signals over-voltage protection

　　A protective position: a multi-functional electronic power substation table, energy acquisition, the electronic power meter to bear a very low voltage levels. As Meter and remote computer stations in the communications equipment used RS232 interfaces, the communication line is longer, and in LVZOB region, near the substation or by direct lightning strike at the substation, proximity to the high voltage sensors, In order to prevent damage to equipment. E-Meter in and around the RS232 port RS232 installation of the over-voltage surge protector. Location should choose to install electronic power meter in and around the port, RS232.

　　The location of protection: electronic power meter through the acquisition of information on the collector's MODEM (modem) from telephone lines to send data to a remote, since the introduction of telephone lines from the outside, the lines on the sensor to sensor lightning current relatively strong, easy to Modem interface equipment damage, it is necessary in the telephone line modem interface, the installation of an interface over-voltage surge protector. Location should choose to install telephone Chuxian inside and outside phone lines-the-line people.

　　3.4.3 distance communication interface over-voltage protection

　　Protective position: Since the basic use of unmanned substation. On the first circuit protection, measurement, control, regulation of signal through the optical and data communications network or carrier to the distance (in tune, and stressed that the centralized control stations, etc.) to transmit data. If the carrier, the carrier and the

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