Common nga mga Sayop ug mga Paraan sa Pagsulay sa 10kV Vacuum Circuit Breakers

Pangutana

Ang 10kV vacuum circuit breaker nagsilbi pinaagi sa paggamit sa vacuum isip insulating ug arc-extinguishing medium tali sa mga contact, kini labi na gamiton sa mga substation ug distribution networks. Subalang ang numero sa mga sayop nga nagsugyot sa iyang espesipikong aplikasyon mahimong adunay dugang. Ang artikulo kini nagkategorya ug naganalisa sa mga karaniwan nga sayop sa iyang operasyon, nagdiskusyon sa iba't ibang klase sa mga paraan sa pagtreat sa sayop, ug nagpakita og regular nga mga panahon sa pag-maintain.

Mga Panahon sa Sayop ug Mga Paraan sa Pagtratado Sa Vacuum Circuit Breaker Same-Same

Ang kauban nga sayop sa 10kV vacuum circuit breaker mao ang baba nga degree sa vacuum sa vacuum interrupter. Ang vacuum circuit breaker nag-interrupt sa current ug nag-extinguish sa arcs sa interior sa vacuum interrupter. Kasagaran, wala gyud ang vacuum circuit breaker gisulod og mga equipment o devices para makwanti ug makwanti ang vacuum-degree characteristics.

Kini mao ang rason kon unsaon ang sayop sa baba nga degree sa vacuum adunay layo nga hidden, ug dili easy detectable sa maintenance ug operational testing. Ang level sa hazard niini labi pa kaysa sa uban nga obvious nga mga sayop. Kung ang degree sa vacuum mobaba hangtod sa di na makaya sa circuit breaker pag-extinguish sa arcs normal, mahimong magresulta sa serious nga mga resulta sama sa burning o explosion sa breaking point.

Rason Sa Baja Na Degree Sa Vacuum Sa Vacuum Interrupter

• Adunay problema sa materyales sa vacuum interrupter, nagdala sa vacuum interrupter mogasakay sa gas, o ang proseso sa pagbuhat dili refined, nagresulta sa adunay leakage points sa vacuum interrupter same-same, tungod niini nagapektuhan ang iyang degree sa vacuum.

• Pagkatapos sa long-time operation, kung ang circuit breaker mogamit og certain action, ang generated vibration mohimo usab sa sealing part sa vacuum interrupter mokompleto, kasagaran nianhi sa baba nga degree sa vacuum sa vacuum interrupter. Especialmente sa vacuum circuit breakers gisulod og CD10 mechanisms, kung ang circuit breaker mogamit og opening ug closing operations sa current, easy mohimo og large impact sa sealing connection part sa vacuum interrupter, nagresulta sa poor sealing ug decrease sa degree sa vacuum.

• Adunay problema sa materyales o pagbuhat sa bellows sa vacuum interrupter, ug adunay leakage points mogawas pagkatapos og multiple operations.

• Ang vacuum interrupter accidental damaged sa routine maintenance work.

Paraan Sa Pagtratado Sa Baja Na Degree Sa Vacuum Sa Vacuum Interrupter

Dapat ma-implement ang preventive tests, ug regular nga check sa degree sa vacuum sa vacuum interrupter. Sa daily inspection ug maintenance sa equipment, dapat frequent conduct sa AC withstand voltage tests (between breaking points). Kung conditions permit, dapat imong gamiton ang vacuum tester para conduct og qualitative test sa degree sa vacuum sa vacuum interrupter aron masiguro nga ang degree sa vacuum sa vacuum interrupter maintained sa certain level aron mapasabot sa operational requirements sa circuit breaker.

Kung mag-select ug install og vacuum circuit breaker, importante nga pilion ang mature products sa manufacturers nga may good reputation ug quality, ug ang iyang supporting mechanism preferentially usa nga may relatively small impact sa circuit breaker. Sa pagpatroly sa equipment, dapat ang maintenance personnel mag-atiman sa observation sa metal shield sa vacuum interrupter kung adunay changes sa color o abnormal sounds sa operasyon.

Sa existing circuit breakers nga severe pollution, timely cleaning ug maintenance sa equipment dapat ma-implement aron maprevent ang dust o uban pang contaminants sa pag-apekto sa insulation performance sa circuit breaker. Kung determine through inspection nga ang vacuum interrupter adunay defects, dapat replace in a timely manner ang vacuum interrupter.

Panahon Sa Sayop Ug Mga Paraan Sa Pagtratado Sa Control Circuit

Ang fuses sa signal circuit blowing ug ang opening ug closing coils burning out kasagaran nga mga sayop sa operating circuit. Ang symptom mao ang circuit breaker dili mag-operate electrically sa opening o closing state, ug ang indicator light dili mag-on. Sa karon, ang microcomputer general na mosend og signal sa "control circuit open-circuit". Ang mga defect niini relatively easy detect ug handle. Mahimo direct check kung ang opening ug closing coils burned out ug magnitude sa resistance deviation. Pwede replace ang problematic coil aron eliminate ang sayop sa operating circuit.

Ang auxiliary contacts sa energy-storage travel switch (CK) dili connected, mainly due to ang travel switch dili adjusted in place o damaged, preventing ang mechanism fully energy-stored. Sa kaso niini, ang energy-storage lamp (usually yellow) dili mag-on. Ang sayop mahimo resolve sa readjusting ang position sa travel switch o replacing ang travel switch aron ensure ang mechanism fully energy-stored.

Ensuring ang kalidad sa travel switch ug improving ang iyang installation reliability among ang main ways aron reduce ang occurrence sa circuit faults. Sa practical operation experience, ang defects sa energy-storage travel switch sa CT19 mechanism kasagaran obvious. Sa closing process sa 10kV circuit breaker, ang air switch sa control power supply tripped, ultimately leading to a control circuit open-circuit. 

Sa karon, ang line's tripping protection action occurred, ug ang faulty line experienced override trip, expanding ang power-outage range ug causing serious impacts. Inspection revealed kung ang travel switch fails operate, ang current loop dili effectively turned off, making it easy for the travel switch to arc when it acts, resulting in a large loop current that causes tripping. By replacing it with equipment of other models, this type of circuit fault can be effectively avoided.

Ang auxiliary switch (contacts) sa circuit breaker damaged or not adjusted in place, causing the circuit unconnected or have poor contact. This generally manifests as a control circuit open-circuit, and the opening and closing indicator lights do not light up or flicker. When this situation occurs, it is necessary to readjust the length of the rotating pull rod of the auxiliary switch or replace the damaged auxiliary switch.

The fault caused by electrical interlocking that prevents the circuit breaker from opening or closing is manifested as follows: the mechanical components of the mechanism work normally, but it cannot be electrically opened or closed, and the positive and negative power supplies cannot be simultaneously supplied to the opening and closing coils. 

This kind of defect generally occurs in equipment with electrical interlocking, such as circuit breakers of capacitor banks, circuit breakers with ground knife interlocking, etc. It is necessary to check whether the mesh doors of the capacitor, the travel (auxiliary) switches of the maintenance ground knife are correctly switched or damaged, and whether the contacts are in good contact, and then carry out corresponding handling.

Additionally, in draw-out switch cabinets, the burning out of components such as energy-storage motors, Y3 relays, and rectifier bridges often occurs, which in turn leads to faults of the control circuit being open-circuited.

There are numerous issues in the control of the operating circuit. Loose terminal connections, poor contacts, and insulation problems of equipment can all cause defects, preventing the circuit breaker from operating properly for opening and closing. When an operating circuit fault occurs, the fault should first be located to identify its source, and then appropriate solutions should be implemented based on the specific situation.

Fault Phenomena and Treatment Methods of Mechanical Failures in Auxiliary and Actuating Mechanisms

When the circuit breaker cannot be opened or closed either electrically or manually, mechanically, the first step is to check whether the mechanism is properly energized. If the energy storage is normal, the problem may be caused by the loosening of the stop piece on the opening and closing half-shaft, insufficient stroke of the opening and closing push rod, or deformation of the opening and closing push rod, which results in jamming or sticking during the opening and closing process, preventing the circuit breaker from operating normally. 

The fault can be addressed by readjusting the stroke of the push rod of the opening and closing coil, fixing the stop piece of the opening and closing half-shaft, and replacing or repairing the defective push rod (changing the copper opening and closing push rod to a steel one to avoid deformation). When the energy storage is abnormal or there are problems in the secondary circuit, the energy-storage motor, travel switch, and control circuit should be inspected for troubleshooting.

The actuating mechanism cannot be energized either electrically or manually. The main reasons are the damage of the one-way bearing in the energy-storage mechanism or the failure of the energy-storage latch to reset (the reset spring is not strong enough or foreign objects jam the reset spring), causing the energy-storage gear to idle. Such faults are prone to occur in CT19-type mechanisms. The problem can be resolved by replacing the one-way bearing in the energy-storage mechanism or replacing (cleaning) the reset spring to restore normal energy storage.

If the opening and closing indication in the actuating mechanism does not match the actual opening and closing position of the circuit breaker body, it may be due to the disconnection of the connecting rod between the mechanism and the main transmission shaft of the circuit breaker. Manually adjust to align the position of the mechanism with that of the circuit breaker, and then reconnect and fix the transmission pull rod.

During the characteristic test, it is found that the low-voltage operation of the circuit breaker is unqualified. When the rated operating voltage is above 65%, the circuit breaker cannot perform reliable opening (it cannot open when the voltage is below 30%, and it may or may not open when the voltage is between 30% and 65%), and it should be able to close reliably at 85% - 110% of the rated voltage. 

When this situation occurs, first check whether the resistance of the coil is within the qualified range. If it is qualified, clean the mechanism, add lubricant to the rotating parts, and then check the engaging depth of the opening and closing half-shaft. If it does not meet the requirements, adjust the adjusting screw for the engaging (inserting) depth of the opening and closing half-shaft (as shown in Figure 1) to meet the requirements (the engaging depth of the CT19-type mechanism is generally 1 - 2mm). 

In addition, an increase in the resistance of the closing coil leading to a decrease in the opening and closing coils, as well as deformation of the opening and closing push rods causing jamming or sticking during opening and closing, will all affect the opening and closing voltage. When dealing with problems, specific handling should be carried out according to the fault situation.

In the draw-out switch equipment, the draw-out switch cannot be moved from the test position to the operating position. The possible causes of such a fault include ground knife interlock failure, deformation of the ground knife interlock linkage plate, failure of the ground knife operation hole linkage plate to reset, and faults in the draw-out switch chassis. The draw-out switch can be moved to the maintenance position. 

Check whether the tongue-shaped interlock plate of the ground knife is deformed or whether this tongue-shaped plate corresponds to the position of the ground knife; check whether the operation hole linkage plate is fully reset; remove the chassis of the draw-out switch and check whether all internal components are in good condition.

Routine Maintenance Measures for Circuit Breakers

When dealing with faults in the circuit breaker mechanism, first analyze the type of fault to determine whether it belongs to an electrical or secondary circuit problem or a mechanical fault, and then proceed with the next-step handling. The method for judging faults is relatively simple. First, make the mechanism fully energized.

If the circuit breaker can be reliably opened and closed manually, mechanical faults can be basically excluded. Then, perform electrical opening and closing. If the opening and closing electromagnets operate but the switch fails to open and close, and the secondary control voltage is normal, it indicates that there are no problems with the secondary circuit. 

For more concealed faults such as reduced vacuum degree, out-of-synchronism in opening and closing, insufficient opening and closing speed, and large bounce, relevant scientific instruments must be used for testing and measurement during maintenance. Problems should be solved through the analysis and judgment of actual measurement data.

In addition to fault repair, certain maintenance work should also be carried out on vacuum circuit breakers in daily work. This includes cleaning the transmission mechanism and insulating support columns to avoid increasing rotational friction, and appropriately adding lubricant to ensure flexible operation. When the vacuum circuit breaker is under outage for maintenance, loop resistance and mechanical characteristic tests should be conducted, and damaged components caused by overheating, etc. of the circuit breaker should be dealt with in a timely manner. 

The fault repair and maintenance work of 10kV circuit breakers has similarities with that of circuit breakers or transformers of other voltage levels in terms of mechanical and secondary circuit fault repair principles. By continuously accumulating experience, technical means can be continuously improved to achieve a better fault elimination rate and maintenance level.

Conclusion

With the rapid development of society, the demand for power supply in all walks of life is constantly increasing, and higher requirements are also put forward for the quality of power supply equipment and the operational stability of the power system. Technical levels and the ability to handle defects need to be continuously improved to meet the needs of development, satisfy the requirements of the majority of users, shorten the time for equipment defect handling and maintenance, and ensure the safe operation of the power grid.

Therefore, during the process of equipment maintenance and renovation, we should strengthen the study of the characteristics of system equipment itself, comprehensively understand the operational characteristics of equipment and the existing problems and potential hazards, strengthen learning and communication, take preventive measures in a timely manner, continuously improve equipment, eliminate safety hazards, prevent accidents, and ensure the safe operation of equipment and the reliability of power supply.