全國服務(wù)熱線:
濟南濟柴環(huán)能燃氣發(fā)電設(shè)備有限公司
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發(fā)電機是一種將機械能轉(zhuǎn)化為電能的設(shè)備,用于產(chǎn)生電力供電或備用電源。然而,由于長時間運行或其他原因,發(fā)電機可能出現(xiàn)各種故障。下面是一些常見的發(fā)電機故障以及對應(yīng)的解決方案。
A generator is a device that converts mechanical energy into electrical energy, used to generate electrical power or backup power. However, due to prolonged operation or other reasons, the generator may experience various malfunctions. Here are some common generator faults and corresponding solutions.
1發(fā)電機進風(fēng)溫度異常升高
1. Abnormal increase in inlet air temperature of generator
處理:
handle:
如果發(fā)電機出風(fēng)溫度、定子線圈溫度未超過規(guī)定時,可不降低發(fā)電機的出力,但應(yīng)查明原因,及時調(diào)整;當(dāng)超過規(guī)定值時,應(yīng)先降低發(fā)電機出力再進行檢查處理。
If the outlet air temperature and stator coil temperature of the generator do not exceed the specified limits, the output of the generator may not be reduced, but the cause should be identified and adjusted in a timely manner; When the specified value is exceeded, the generator output should be reduced first before inspection and handling.
2發(fā)電機線圈和鐵芯溫度異常升高
2. Abnormal increase in temperature of generator coils and iron cores
處理:
handle:
如果超過規(guī)定值時,應(yīng)迅速降低負(fù)荷。
If the specified value is exceeded, the load should be quickly reduced.
迅速檢查冷卻空氣溫度,并檢查濾塵器是否堵塞;
Quickly check the temperature of the cooling air and check if the dust filter is clogged;
檢查空冷器出入口閥門是否關(guān)閉。
Check if the inlet and outlet valves of the air cooler are closed.
3發(fā)電機過負(fù)荷
3 Generator overload
發(fā)電機允許短時過負(fù)荷運行,過負(fù)荷的參數(shù)及時間按下表確定:
The generator is allowed to operate under short-term overload, and the parameters and time of overload are determined according to the following table:
過負(fù)荷時,要在規(guī)定的時間內(nèi)把負(fù)荷電流降至允許值內(nèi),同時還要監(jiān)視發(fā)電機各部溫度不超標(biāo)。
When overloaded, the load current should be reduced to the allowable value within the specified time, and the temperature of each part of the generator should be monitored to ensure that it does not exceed the standard.
4發(fā)電機三相不平衡電流超標(biāo)
The three-phase unbalanced current of the generator exceeds the standard
處理:
handle:
發(fā)電機三相不平衡電流超過規(guī)定時,應(yīng)首先檢查是否由于互感器回路故障引起,否則應(yīng)降低定子電流使其不超過規(guī)定值,同時還應(yīng)嚴(yán)密監(jiān)視發(fā)電機各部溫度,當(dāng)發(fā)現(xiàn)溫度異常升高,不平衡電流增加時,應(yīng)緊急解列停機。如果并網(wǎng)運行,不平衡電流沒有超過額定值10%,減小外送有功,看不平衡電流是否變小,如果變小,是外網(wǎng)引起的。可以維持運行?;驍嚅_外網(wǎng)。
When the three-phase unbalanced current of the generator exceeds the specified value, the first thing to check is whether it is caused by a fault in the transformer circuit. Otherwise, the stator current should be reduced to not exceed the specified value. At the same time, the temperature of each part of the generator should be closely monitored. When the temperature rises abnormally and the unbalanced current increases, emergency disconnection and shutdown should be carried out. If the unbalanced current does not exceed 10% of the rated value during grid connected operation, reduce the external active power and see if the unbalanced current decreases. If it decreases, it is caused by the external grid. Can maintain operation. Or disconnect from the external network.
5發(fā)電機運行中指示表計之一突然指示失?;蛳?/p>
During the operation of the generator, one of the indicators suddenly shows abnormal or disappears readings
處理:
handle:
應(yīng)參照其余表計的指示,檢查是否由于儀表本身或其一、二次回路的損壞引起,如果二次回路導(dǎo)線損壞,盡可能不改變發(fā)電機的運行方式;如果影響發(fā)電機的正常運行時,應(yīng)根據(jù)實際情況減少負(fù)荷或停機處理。
Refer to the instructions of other meters and check if it is caused by damage to the instrument itself or its primary and secondary circuits. If the secondary circuit wires are damaged, try not to change the operation mode of the generator as much as possible; If it affects the normal operation of the generator, the load should be reduced or the machine should be shut down according to the actual situation.
6發(fā)電機機端PT二次電壓消失
6. The PT secondary voltage at the generator terminal disappears
現(xiàn)象:
Phenomenon:
警鈴響,“發(fā)電機機端PT斷線”報警。
The alarm bell rings, and the "generator terminal PT disconnection" alarm is triggered.
發(fā)電機有功、無功、電壓表指示降低或為零。
The active, reactive, and voltmeter readings of the generator decrease or reach zero.
處理:
handle:
將自動調(diào)節(jié)勵磁系統(tǒng)改為手動方式運行;
Change the automatic excitation system to manual operation mode;
退出發(fā)電機復(fù)合電壓閉鎖過流保護;
Exit the generator compound voltage lockout overcurrent protection;
通過其它表計對發(fā)電機進行監(jiān)視調(diào)整;
Monitor and adjust the generator through other meters;
通知汽機注意監(jiān)視發(fā)電機。
Notify the turbine to monitor the generator carefully.
檢查機端PT回路,如果一、二次保險熔斷,應(yīng)予以更換;
Check the PT circuit at the machine end. If the primary and secondary fuses are blown, they should be replaced;
正常后,投入發(fā)電機復(fù)合電壓閉鎖過流保護,將勵磁調(diào)節(jié)方式改為自動方式運行。
After normal operation, activate the generator's composite voltage lockout overcurrent protection and change the excitation regulation mode to automatic operation.
7發(fā)電機勵磁PT二次電壓消失
7 Generator excitation PT secondary voltage disappears
現(xiàn)象:
Phenomenon:
警鈴響,“發(fā)電機勵PT斷線”報警。
The alarm bell rings, and the "generator excitation PT disconnection" alarm is triggered.
勵磁調(diào)節(jié)屏發(fā)電機機端電壓表指示到零。
The excitation control panel generator terminal voltmeter indicates zero.
處理:
handle:
將勵磁調(diào)節(jié)方式改為手動方式運行;
Change the excitation regulation mode to manual operation;
檢查勵磁PT回路,如果一、二次保險熔斷,應(yīng)予以更換;
Check the excitation PT circuit. If the primary and secondary fuses are blown, they should be replaced;
恢復(fù)正常后,將勵磁調(diào)節(jié)方式改為自動方式運行。
After returning to normal, change the excitation regulation mode to automatic operation.
8發(fā)電機升不起電壓
8. The generator cannot raise the voltage
現(xiàn)象:發(fā)電機升壓時電壓表無指示或很低。
Phenomenon: When the generator is boosting, the voltmeter shows no indication or is very low.
處理:
handle:
檢查勵磁調(diào)節(jié)系統(tǒng)是否正常;
Check if the excitation regulation system is functioning properly;
檢查表計及PT一、二次回路是否正常;
Check whether the meter and PT primary and secondary circuits are normal;
測量勵磁變高、低壓側(cè)絕緣電阻是否合格;
Measure whether the insulation resistance on the high and low voltage sides of the excitation transformer is qualified;
9差動CT斷線
9. Differential CT disconnection
現(xiàn)象:警鈴響,“差動CT斷線”報警。
Phenomenon: The alarm bell rings and the "differential CT disconnection" alarm sounds.
處理:
handle:
通過保護裝置電流監(jiān)測功能檢查差動CT回路是否確實斷線;
Check whether the differential CT circuit is indeed disconnected through the current monitoring function of the protective device;
如果差動CT回路確實斷線,則應(yīng)暫時退出差動保護;
If the differential CT circuit is indeed disconnected, the differential protection should be temporarily exited;
檢查差動CT回路接線端子是否接觸良好;
Check if the differential CT circuit wiring terminals are in good contact;
檢查各差動CT本體有無異常;
Check for any abnormalities in each differential CT body;
恢復(fù)正常后,投入差動保護。
After returning to normal, activate differential protection.
10發(fā)電機內(nèi)部故障
Internal fault of generator 10
現(xiàn)象:
Phenomenon:
警鈴響,“發(fā)電機差動保護動作”或“定子接地保護動作”、“主汽門關(guān)閉” 報警。
The alarm bell rings, and the "generator differential protection action" or "stator grounding protection action" and "main steam valve closed" alarms.
發(fā)電機表計指示劇烈擺動后到零。
The generator meter indicates a severe swing and then reaches zero.
發(fā)電機主開關(guān)與滅磁開關(guān)跳閘。
The main switch and demagnetization switch of the generator tripped.
處理:
handle:
檢查并記錄保護動作情況。
Check and record the protective actions.
對發(fā)電機及其有關(guān)設(shè)備和所有在保護區(qū)的電氣回路作詳細的外部檢查,查明有 無故障,同時詢問電網(wǎng)有無故障,如確有故障,待消除后恢復(fù)運行。
Conduct a detailed external inspection of the generator and its related equipment, as well as all electrical circuits within the protected area, to determine if there are any faults. At the same time, inquire about any faults in the power grid. If there are indeed faults, they will be resolved before resuming operation.
若未發(fā)現(xiàn)明顯故障點,在測量定、轉(zhuǎn)子線圈絕緣電阻合格后,可申請值長將發(fā)電機零起升壓,升壓時發(fā)現(xiàn)不正常立即停機,未發(fā)現(xiàn)異??刹⑷腚娋W(wǎng)運行。
If no obvious fault point is found, after measuring the insulation resistance of the stator and rotor coils and passing the test, the shift supervisor can be applied to increase the voltage of the generator from zero. If any abnormality is found during the voltage increase, the generator should be immediately shut down. If no abnormality is found, it can be connected to the power grid for operation.
11發(fā)電機外部故障
External fault of generator 11
現(xiàn)象:
Phenomenon:
警鈴響,“發(fā)電機復(fù)合電壓閉鎖過流保護動作”電腦報警亮。
The alarm bell rings, and the computer alarm lights up for the "Generator Compound Voltage Lockout Overcurrent Protection Action".
定子電流表突然劇增,電壓劇降。
The stator ammeter suddenly increases sharply and the voltage drops sharply.
處理:
handle:
發(fā)電機外部長時間故障,電流表指示最大,電壓急劇降低時,值班員應(yīng)立即手動解列發(fā)電機;如果定時過流保護切斷發(fā)電機主開關(guān),同時內(nèi)部故障保護未動作,經(jīng)外部檢查未發(fā)現(xiàn)明顯不正?,F(xiàn)象時,可待其它系統(tǒng)正常后將發(fā)電機并網(wǎng)運行。
When the external fault of the generator lasts for a long time, the ammeter indicates the maximum, and the voltage drops sharply, the duty officer should immediately manually disconnect the generator; If the timed overcurrent protection cuts off the main switch of the generator and the internal fault protection does not operate, and no obvious abnormal phenomenon is found after external inspection, the generator can be connected to the grid for operation after other systems are normal.
12發(fā)電機轉(zhuǎn)子一點接地
12. One point grounding of generator rotor
現(xiàn)象:警鈴響,“轉(zhuǎn)子一點接地”報警。
Phenomenon: The alarm bell rings and the "rotor is grounded at one point" alarm sounds.
處理:
handle:
檢查保護裝置內(nèi)接地情況,及兩點接地保護是否在跳閘位置,否則應(yīng)立即將其投至跳閘位置;
Check the grounding condition inside the protective device and whether the two-point grounding protection is in the tripping position. Otherwise, it should be immediately put into the tripping position;
檢查轉(zhuǎn)子滑環(huán)處有無過熱,積灰、油污,并設(shè)法清理;
Check for overheating, dust accumulation, and oil stains at the rotor slip ring, and try to clean it up;
當(dāng)一點接地的同時或查找一點接地的過程中發(fā)電機有失磁現(xiàn)象時,應(yīng)立即解列停機。
When there is a demagnetization phenomenon in the generator during the process of grounding or finding a grounding point, it should be immediately disconnected and stopped.
若確定為轉(zhuǎn)子內(nèi)部一點接地時,則應(yīng)申請值長停機處理。
If it is determined that there is a grounding point inside the rotor, the shift chief operator should be requested to stop the machine for processing.
13發(fā)電機變同步電動機運行
13 Generator to Synchronous Motor Operation
現(xiàn)象:
Phenomenon:
警鈴響,“主汽門關(guān)閉”電腦報警亮。
The alarm bell rings, and the computer alarm lights up when the main throttle valve is closed.
發(fā)電機有功表指示零值以下,無功表指示升高。
The active power meter of the generator indicates a value below zero, while the reactive power meter indicates an increase.
發(fā)電機定子電流降低,定子電壓升高。
The stator current of the generator decreases and the stator voltage increases.
勵磁電壓和電流略有降低。
The excitation voltage and current have slightly decreased.
進線有可能過負(fù)荷,或指針滿盤。
The incoming line may be overloaded or the pointer may be full.
處理 :
handle:
主汽門聯(lián)跳發(fā)電機保護應(yīng)動作解列停機,否則應(yīng)手動解列停機。若主汽門關(guān)閉后,同時接到汽機方“機器危險”通知,應(yīng)立即手動解列發(fā)電機。
The main steam valve tripping generator protection should be activated to disconnect and shut down, otherwise it should be manually disconnected and shut down. If the main steam valve is closed and a "machine danger" notice is received from the turbine side, the generator should be manually disconnected immediately.
14發(fā)電機振蕩
14 Generator oscillation
原因:
Reason:
由于系統(tǒng)故障引起
Due to system malfunction
發(fā)電機失磁或欠磁引起
Generator demagnetization or under magnetization caused
人員誤操作
Personnel misoperation
現(xiàn)象:
Phenomenon:
定子電流表往復(fù)擺動,通常電流超過額定值。
The stator ammeter oscillates back and forth, and the current usually exceeds the rated value.
定子電壓表指針劇烈擺動,通常電壓指示降低。
The pointer of the stator voltmeter swings violently, usually causing a decrease in voltage indication.
有功、無功表指針劇烈擺動。
The pointers of the active and reactive power meters swing violently.
發(fā)電機發(fā)生有節(jié)奏的鳴聲,且與表計擺動合擺。
The generator produces a rhythmic sound and oscillates in conjunction with the meter.
如果發(fā)電機與系統(tǒng)同步振蕩,發(fā)電機表計與系統(tǒng)表計擺動一致;如果發(fā)電機與系統(tǒng)發(fā)生振蕩,則發(fā)電機表計與系統(tǒng)擺動相反。
If the generator oscillates synchronously with the system, the oscillation of the generator meter and the system meter will be consistent; If the generator oscillates with the system, the generator meter will oscillate in the opposite direction to the system.
處理:
handle:
若發(fā)生趨向穩(wěn)定的振蕩,則不需要操作,但要做好處理事故的準(zhǔn)備。
If a stable oscillation occurs, no operation is required, but preparation should be made to handle the accident.
如果振蕩無減小的趨勢,則應(yīng)立即通知汽機降低發(fā)電機有功負(fù)荷,并立即增加發(fā)電機的勵磁電流,當(dāng)采用自動勵磁時,嚴(yán)禁干擾調(diào)節(jié)器動作。
If there is no decreasing trend in oscillation, the turbine should be immediately notified to reduce the active load of the generator and increase the excitation current of the generator. When using automatic excitation, it is strictly prohibited to interfere with the operation of the regulator.
如果振蕩由于發(fā)電機誤并列引起,應(yīng)立即將發(fā)電機解列。
If oscillation is caused by generator misalignment, the generator should be disconnected immediately.
值班員采取措施后,在兩分鐘內(nèi)無法將發(fā)電機投入同步,則應(yīng)將發(fā)電機解列。
If the duty officer fails to synchronize the generator within two minutes after taking measures, the generator should be disconnected.
15發(fā)電機解列時發(fā)生非全相運行
Non full phase operation occurs when the 15 generators are disconnected
現(xiàn)象:
Phenomenon:
發(fā)電機解列時定子三相電流表指示不平衡,機組發(fā)生振動。
When the generator is disconnected, the stator three-phase ammeter indicates imbalance and the unit vibrates.
處理:
handle:
手動再拉一次開關(guān),如不成功,則聯(lián)系汽機維持轉(zhuǎn)速3000r/min,將發(fā)電機重新同期并入系統(tǒng)。
Manually pull the switch again. If unsuccessful, contact the turbine to maintain a speed of 3000r/min and synchronize the generator back into the system.
并入系統(tǒng)后,聯(lián)系裝置區(qū)倒負(fù)荷,用上一級開關(guān)將發(fā)電機解列。
After integration into the system, contact the device area to reverse the load and use the higher-level switch to disconnect the generator.
如果發(fā)電機無法并入系統(tǒng),應(yīng)立即拉開發(fā)電機上一級開關(guān)及發(fā)電機側(cè)母線上的線路開關(guān)。
If the generator cannot be integrated into the system, the upper level switch of the generator and the line switch on the generator side busbar should be immediately opened.
16發(fā)電機主開關(guān)跳閘
16 Generator main switch tripped
處理:
handle:
立即檢查滅磁開關(guān)是否跳開,否則應(yīng)立即手動將其斷開。
Immediately check if the demagnetization switch has tripped, otherwise it should be manually disconnected immediately.
檢查系統(tǒng)聯(lián)絡(luò)線情況,根據(jù)主系統(tǒng)運行規(guī)程做進一步處理;
Check the status of the system communication line and take further actions according to the operating procedures of the main system;
檢查何種保護動作,保護動作值,判斷故障后,匯報領(lǐng)導(dǎo)處理;
Check what protective actions are taken, the protective action values, determine the fault, and report to the leader for handling;
若為人員誤動,可不經(jīng)檢查,將發(fā)電機并列。
If it is due to personnel error, the generator can be connected in parallel without inspection.
17發(fā)電機失磁
17 Generator demagnetization
現(xiàn)象:
Phenomenon:
警鈴響,“失磁保護動作”電腦報警亮。發(fā)電機無功負(fù)荷降至零值以下。
The alarm bell rings, and the "demagnetization protection action" computer alarm lights up. The reactive load of the generator drops below zero.
發(fā)電機勵磁電壓降低,勵磁電流到零。
The excitation voltage of the generator decreases and the excitation current reaches zero.
發(fā)電機定子電壓降低,定子電流明顯增加。
The stator voltage of the generator decreases, and the stator current increases significantly.
有功擺動并降低,無功指示零值以下。
Active power swings and decreases, while reactive power indicates a value below zero.
線路電流滿盤或?qū)?cè)開關(guān)跳閘。
The line current is full or the switch on the opposite side trips.
處理:
handle:
發(fā)電機失去勵磁時,失磁保護應(yīng)動作解列發(fā)電機;當(dāng)失磁保護未動或開關(guān)拒跳時,應(yīng)立即手動解列停機。
When the generator loses excitation, the demagnetization protection should activate to disconnect the generator; When the demagnetization protection is not activated or the switch refuses to trip, the machine should be manually disconnected and stopped immediately.
解列后,對發(fā)電機勵磁回路進行檢查處理,無問題后,將發(fā)電機并入系統(tǒng)。
After disconnection, check and handle the excitation circuit of the generator. If there are no problems, connect the generator to the system.
18發(fā)電機非同期并列
18 Generator Non synchronous Parallel
現(xiàn)象:
Phenomenon:
在合上待并發(fā)電機主開關(guān)的瞬間,定子電流突然劇增,定子電壓降低,發(fā)電機本體發(fā)出吼聲,然后定子電流劇烈擺動或引起保護動作跳閘。
At the moment of closing the main switch of the standby generator, the stator current suddenly increases sharply, the stator voltage decreases, the generator body makes a roar, and then the stator current swings violently or causes the protection action to trip.
處理:
handle:
若保護未動,應(yīng)立即手動斷開發(fā)電機主開關(guān)與滅磁開關(guān)解列發(fā)電機。
If the protection is not activated, the generator main switch and demagnetization switch should be manually disconnected immediately to disconnect the generator.
待發(fā)電機停止轉(zhuǎn)動后,測量定子線圈絕緣電阻。
After the motor stops rotating, measure the insulation resistance of the stator coil.
打開發(fā)電機端蓋,檢查定子線圈端部有無變形。
Open the generator end cover and check for any deformation at the end of the stator coil.
在查明發(fā)電機確未受損及非同期并列的原因,經(jīng)總工批準(zhǔn),再次將發(fā)電機并入系統(tǒng)。
After confirming that the generator was not damaged and the reason for the asynchronous parallel connection was confirmed, with the approval of the chief engineer, the generator was once again integrated into the system.
19發(fā)電機或勵磁變著火
19 Generator or excitation transformer catches fire
原因:
Reason:
繞組絕緣擊穿;
Winding insulation breakdown;
導(dǎo)線及接頭過熱。
The wires and connectors are overheating.
現(xiàn)象:
Phenomenon:
發(fā)電機窺視孔中可見到火星、煙霧;
Mars and smoke can be seen in the peephole of the generator;
勵磁變本體冒煙著火;
The excitation transformer body is smoking and catching fire;
發(fā)電機勵磁變周圍有很強的絕緣焦臭味。
There is a strong smell of insulation burning around the excitation transformer of the generator.
處理:
handle:
立即解列停機。
Immediately disconnect and shut down.
如解列后火勢仍不減,應(yīng)向發(fā)電機內(nèi)注水,勵磁變1211滅火器滅火。
If the fire still does not subside after disconnection, water should be injected into the generator and the 1211 fire extinguisher of the excitation transformer should be used to extinguish the fire.
維持發(fā)電機300r/min運行。
Maintain the generator running at 300r/min.
保護事故現(xiàn)場,分析事故原因。
Protect the accident scene and analyze the cause of the accident.
20發(fā)電機震蕩與失步
20 Generator Vibration and Out of Step
現(xiàn)象:
Phenomenon:
發(fā)電機正常運行時發(fā)出的功率和用戶的負(fù)荷功率是平衡的,發(fā)電機和系統(tǒng)都在穩(wěn)定狀態(tài)下運行。當(dāng)系統(tǒng)中發(fā)生某些重大擾動時,發(fā)電機與用戶的有功平衡將遭到破壞。此時必須立即改變發(fā)電機的輸出功率。
The power generated by the generator during normal operation is balanced with the load power of the user, and both the generator and the system are operating in a stable state. When significant disturbances occur in the system, the active power balance between the generator and the user will be disrupted. At this point, the output power of the generator must be immediately changed.
但由于發(fā)電機轉(zhuǎn)子的轉(zhuǎn)動慣性作用,汽輪機的調(diào)速器的動作需要一定的延時,故改變發(fā)電機的功率就需要有一個過程,在這個過程中,發(fā)電機的功率與用戶的功率不能平衡,就會破壞發(fā)電機穩(wěn)定運行,使發(fā)電機發(fā)生振蕩。
However, due to the rotational inertia of the generator rotor, the action of the turbine governor requires a certain delay, so changing the power of the generator requires a process. During this process, the power of the generator cannot be balanced with that of the user, which will disrupt the stable operation of the generator and cause oscillation.
處理:
handle:
如果事故不嚴(yán)重,汽輪機調(diào)速動作較靈敏則發(fā)電機的電流、電壓及功率經(jīng)短時間波動后,會恢復(fù)到功率平衡,如果事故很嚴(yán)重,汽輪機的調(diào)速器的動作很遲鈍,則會使個別發(fā)電機與系統(tǒng)之間發(fā)生激烈振蕩,另一瞬間又從系統(tǒng)吸收功率,這種功率來回傳遞,可能發(fā)展到使發(fā)電機與系統(tǒng)之間失去同步。
If the accident is not serious and the speed regulation action of the steam turbine is sensitive, the current, voltage, and power of the generator will return to power balance after a short period of fluctuation. If the accident is serious and the speed regulation action of the steam turbine is slow, it will cause intense oscillations between individual generators and the system, and at another moment absorb power from the system. This power is transmitted back and forth and may develop into a loss of synchronization between the generator and the system.
本文由 沼氣發(fā)電機組 友情奉獻.更多有關(guān)的知識請點擊 http://www.shgcmy.com/ 真誠的態(tài)度.為您提供為全面的服務(wù).更多有關(guān)的知識我們將會陸續(xù)向大家奉獻.敬請期待.
This article is a friendly contribution from a biogas generator set For more related knowledge, please click http://www.shgcmy.com/ Sincere attitude To provide you with comprehensive services We will gradually contribute more relevant knowledge to everyone Coming soon.

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