Keywords substation; GIS; abnormalities and faults
Substation is the basic organization of the power system, in operation will occur in a variety of anomalies or accidents, and these anomalies or accidents are likely to bring great harm to the power system as well as industrial and agricultural production, etc., at this time, to be able to correctly and promptly deal with the various abnormalities or accidents, is the operation of the substation duty personnel An important basic responsibility [1]. Sulfur hexafluoride closed combination of electrical appliances, internationally known as "gas insulated switchgear" (Gas Insulated Switchgear) referred to as GIS [2], which will be a substation in addition to the transformer in the primary equipment, including circuit breakers, disconnecting switches, grounding switches, voltage transformers, current transformers, surge arresters, bus barriers and other equipment. Transformer, surge arrester, busbar, cable terminals, inlet and outlet casing, etc., through the optimization of the design of the organic combination into a whole. This paper analyzes some abnormal operation and faults of substation GIS combined electrical equipment and puts forward corresponding treatment methods.
I, the causes of failure
1, the manufacturer: manufacturing workshop cleanliness caused by metal particles, dust and other debris left inside the GIS; assembly errors caused by friction of components produced metal powder left in the hidden parts of the parts; non-compliance with the process caused by the parts of the wrong installation, leakage phenomenon; the quality of the material is unqualified.
2, installation: installation site cleanliness is poor, resulting in moisture, corrosion of insulating parts, external dust, debris invasion of the GIS internal; do not comply with the process procedures resulting in parts installed wrongly, leakage phenomenon; and other works caused by the cross operation of foreign objects into the GIS internal.
Second, the GIS combination of abnormal electrical equipment and troubleshooting methods
1, GIS circuit breaker troubleshooting methods
(1) GIS circuit breaker refuses to close the gate:
1) If the circuit breaker is operated by the power supply power outage, the operating personnel should check the circuit breaker operating power supply is open or fuses, if it is found to be operated by the power supply is open or fuse, the operating personnel should try to close the circuit breaker. If it is found that the operating power supply is open or the fuse is broken, the operator should try to close the open or replace the fuse, and should also check whether the switch "remote - local" selector switch in the convergence control cabinet is in the remote position;
2) If it is a problem of the control circuit, it should be focused on checking the control back to the easy to fault location, such as the same period of the circuit, the control switches, closing coils, split-phase operation box, relays, etc. For the secondary circuit problems, it is important to check the control circuit to ensure the safety of the circuit breaker. Relay, etc., for the secondary circuit problems, generally should be notified to the professionals to deal with;
3) If the convergence control cabinet "remote - local" control handle placed in the local position or poor contact contact, then the "remote - local" control handle can be If the circuit breaker SF6 pressure is lowered and the switch is blocked, the operator should disconnect the circuit breaker from the operating power supply, apply for decommissioning reclosing, and notify the professionals to deal with the problem;
6) If the circuit breaker cannot be put into operation due to a fault, the operator should report to the dispatching to isolate the circuit breaker (by disconnecting the isolation switches on both sides of the circuit breaker) and wait for the professionals to deal with the problem.
(2) GIS circuit breaker refuses to open the gate to deal with:
1) If the power supply is broken, the operator should check whether the circuit breaker operating power supply is open or fuse, if it is found to be the operating power supply is open or fuse blown, the operator should try to close the open or replace the fuse, and should also check the switch in the convergence control cabinet, "Remote - local" selector switch is indeed in the control cabinet, "Remote - local" selector switch is in the control cabinet, "Remote - local" selector switch is in the control cabinet, "Remote - local" selector switch is in the control cabinet.
3) If the auxiliary contact of the circuit breaker is poorly converted, notify the professionals to deal with it;
4) If the "remote - local" handle position in the convergence control cabinet is in the local position, the handle should be placed in the corresponding position; if the handle auxiliary contact is poorly converted, notify the professionals to deal with it;
5) If the spring mechanism does not store energy, check whether the power supply is intact or not. If it belongs to the mechanism problem should notify the professionals to deal with;
6) If it is the circuit breaker SF6 pressure reduction blocking switch, the operator should disconnect the circuit breaker operating power supply air open, apply for deactivation of the reclosing, report to the scheduling, notify the professionals to deal with;
7) When the fault caused by the circuit breaker can not be divided, the operator should immediately report to the scheduling, agreed by the scheduling with the mother of the string substitute faulty Breaker, that is, non-fault outgoing circuit breaker inverted to another bus, with the bus circuit breaker to remove the fault breaker; and the fault breaker connected to the section of the bus to maintenance, notify the professionals to deal with.
2, GIS circuit breaker operating mechanism abnormal treatment
(1) GIS circuit breaker hydraulic operating mechanism abnormal treatment:
The occurrence of the hydraulic mechanism of the oil level or oil leakage caused by serious circuit breaker closing blocking, the operating personnel should cut off the power supply of its motor, immediately report to the scheduling, the scheduling agreed to the use of the bus switch tandem substitute faulty circuit breaker, that is, non-faulty outlet circuit breaker reversed to another bus The circuit breaker is inverted to another bus, and the faulty circuit breaker is removed by the bus breaker; the section of the bus connected to the faulty circuit breaker is transferred to maintenance, and the professionals are notified to deal with it.
(2) GIS equipment disconnecting switch operating mechanism abnormal treatment:
1) normal operation of the GIS equipment disconnecting switch, such as can not be motorized operation, the operator should check the control circuit voltage or motor voltage to see whether the control circuit voltage or motor voltage to see whether it is too low or loss of voltage, such as belonging to the low or loss of voltage should be immediately restored, and to check the thermal relay action, if the thermal relay action should be pressed the thermal relay reset button. If the thermal relay operates, press the thermal relay reset button. When electric operation is not possible, manual operation should be carried out, and the power supply should be disconnected before operation.
2) If even manual operation is not possible, when the bus-side disconnecting switch cannot be operated, report to the dispatch immediately, and with the dispatch's consent, immediately invert the non-faulty outgoing circuit breaker to another bus, transfer the bus to which the faulty disconnecting switch is connected to overhaul, and also transfer the switch to overhaul, and then notify the overhaul personnel to deal with the problem; the line side of the disconnecting switch can't be operated, report to the dispatch immediately, and with the dispatch's consent, immediately report to the dispatch, and with the consent of the dispatch, report to the dispatch immediately. In the case of ensuring that the switch has been disconnected, disconnect the isolation switch on the bus side, de-energize the side and transfer to maintenance (the opposite side of the line should be transferred to maintenance), and then notify the maintenance personnel to deal with.
3, GIS combination of electrical equipment encountered SF6 gas pressure reduction fault processing methods:
1) when the operator found GIS combination of electrical equipment SF6 gas reduced to the alarm value should be reported to the operation and maintenance department, by the maintenance personnel to make up for the gas;
2) when the operator found GIS combination of electrical equipment SF6 gas reduced to the value of the lockout Should immediately should pull the operating power supply, and lock the operating mechanism, in the manual operating handle hanging prohibited operation of the sign, immediately report to the dispatching, according to the order, take measures to isolate the fault switch; report to the department to notify the operation and maintenance department to deal with.
4, GIS combined electrical equipment in the event of SF6 serious gas leakage fault processing methods:
1) should immediately disconnect the switch's operating power supply, in the manual operation of the handle to hang a "no operation" sign;
2) report to the scheduling, according to the scheduling order, take measures to isolate the faulty switch;
3) the switch will not be operated. The faulty switch will be isolated according to the dispatching order;
3) Be careful when approaching the equipment, try to choose to approach the equipment from the "upwind", and wear gas masks and protective clothing if necessary.
5, GIS combined electrical equipment accidental explosion handling:
SF6 equipment accidental explosion, accident personnel approaching the equipment to be cautious, outdoor equipment, try to choose to approach the equipment from the wind. When dealing with SF6 gas leakage in large quantities, emergency treatment precautions:
1) personnel into the outdoor equipment within 10m, must wear protective clothing, protective gloves and gas masks;
2) in the outdoor should stand in the wind to work.
References
[1]Jia Ye. Research on substation troubleshooting training guidance system[J]. Grid Technology,2006.10:292-294.
[2]Meng Yu. Analyzing the advantages and disadvantages of GIS combined electrical appliances in the application, safety protection and emergency treatment[J]. Inner Mongolia Petrochemistry.2008.10:58.
1Song Jie, 1969.12, male, Bengbu, Anhui Province, engineer, currently deputy director of the substation engineering area of Huainan Power Supply Company.
2Chen Guanbiao, 1972.11, male, native of Huainan, Anhui Province, assistant engineer, senior technician, currently shift manager of 220KV Ancheng centralized control center of Huainan Power Supply Company.