1, do a good job in relay protection acceptance relay commissioning is completed, strict self-test, professional acceptance, and then submitted to the inspection and acceptance by the Ministry of organization and maintenance, operation, production of three departments to protect the entire group of experiments, switch Hop jump test, Qualified and confirmed that the demolition of the wiring, components, signs, pressure plate has returned to normal, on-site civilized health clean, the receipt of the signature.
When the setting of protection or secondary circuit is changed, check the setting or protection circuit with the relevant precautions, and record the contents of the change of the protection device, the time, the person responsible for the change, and the signature of the operation monitor on the change book. Protection of the transformation of the main equipment but also for trial operation or commissioning test, such as: differential protection take CT replacement, it should be hexagonal experiment qualified before commissioning.
2, strict relay protection device and its secondary circuit inspection Patrol inspection equipment is timely detection of hidden dangers, an important way to avoid accidents, but also the power plant on duty an important task.
In addition to the shift inspection, the class arrange a more detailed and detailed examination. Patrol inspection of the relay protection are as follows: the protection of pressure plate, automatic devices are required by the scheduling input; switch, platen position is correct; the circuit wiring is normal, no loose, fever and smell of coke smell exists; fuse contact; relay Contact intact, charged contacts without large jitter and burnout, the coil and additional resistance without overheating; CT, PT loop were no open, short circuit; indicator light, running monitor light indicates normal; meter parameters meet the requirements; light plate , Alarm, accident sound intact; computer protection printer action, should also check the report of the time and parameters, when the report was found to be abnormal, promptly notify the security staff to deal with.
3, to improve the accuracy of relay operation
(1) After learning the principle of protection and secondary drawings, operators should check and familiarize with the secondary circuit terminals, relays, signal cards and pressure plate on the scene. Strict "two votes" of the implementation, and to implement the protection of security measures ticket, in accordance with the relay protection operation procedures. Each input, exit, to be strictly in accordance with the scope of equipment scheduling division, agreed to dispatch. In order to ensure the accuracy of investment protection, in the operating procedures incorporated into the protection of the name, pressure plate, time limit, the protection switch and the use of pressure plate instructions. As the provisions of a clear, strict implementation, reduce the time on duty to inspect the protection map, to avoid running errors.
(2) The protection operation under special circumstances, except that some of them are clearly stipulated in the rules, the operators are mainly learned through training and learning. The request can not be stopped DC power supply instead of stop protection; PT overhaul, should notify the security staff to monitor the pressure 3YJ contact shorted and the direction of component short circuit; bypass bypass line on behalf of the establishment, the protection of the value transferred to the On behalf of the line the same value; phase contrast type bus differential protection in the mother of the switch on behalf of the line, you must switch CT terminal. Special attention should be paid to start the protection of other switches Lianpian, promptly exit the pressure plate. Common are: 100MW unit wiring unit of the high-pressure plant variable differential, heavy-watt multi-link mainframe, the main transformer switch protection; bus failure jump main transformer, line switch protection; line power cut-off protection; Jump mother switch protection; plant spare branch over-current jump to spare section protection.
(3) If there is any abnormality or defect in the operation of relay protection, in addition to strengthening the surveillance, the export pressure plate can be retreated to the protection that can cause malfunction, and then contact the following persons to handle it. If the following unusual circumstances, should be promptly withdrawn.
①Bus ​​differential protection When sending "Busbar AC line break", "Bus differential DC voltage disappears" signal; Busheight imbalance current is not zero; Busbar switch bypass bus without dedicated bypass bus operation and recovery Brake operation.
â‘¡ high-frequency protection when the DC power disappears; regular channel test parameters do not meet the requirements; device failure or abnormal channel signal issued can not be reset; next mother on behalf of the line switch operation.
â‘¢ distance protection When using the PT to exit the operation or three-phase voltage loop is broken; normally magnetic flux is too large, too small; load current exceeds the allowable current protection section.
(4) When the alarm light of one of the four protection (high frequency, distance, zero sequence, comprehensive weight) is on, exit the corresponding protection; if both CPUs fail, they should exit all protection of the device; If the power indicator is off, it indicates that DC has disappeared. Exit the exit pressure plate and put it back in after the restoration of DC power supply. The total alarm light and call light are on, and the CPU × ERR signal is printed. If the CPU is normal, the protection and interface CPU If the signal can not be reset, it indicates that the CPU has a fatal flaw and should exit the protection export pressure plate and disconnect the inspection switch.
⑤ gas protection in the transformer operation refueling, oil or change silicone; submersible pump or oil cooler (radiator) put into the oil after overhaul; need to open the respiratory system drain valve or drain plug, or when cleaning the moisture absorber ; On-load voltage regulator switch oil when someone working.
â‘¥ reclosing in the line when the number of switching trips over the limit (usually 110 kV less oil switch allows 5 times, 220 kV less oil switch allows 7 times; LW Series 110 kVSF6 switch 65 times, 220 kVSF6 switch 50 times, or switch to overhaul ); System short circuit capacity increases, the circuit breaker breaking capacity can not meet a coincidence requirements; no voltage test voltage extraction device failure or contemporaneous test from the bus PT secondary voltage is not normal; circuit breaker pressure or hydraulic pressure To not allow the value of reclosing operation or locked.
4, do a good job of protection action analysis After the protection of the trip, is strictly prohibited immediately return the card signal, but should check the action and identify the reasons for doing a good record.
Before the resumption of power transmission, all the cards can be put back all the signs and resume operation of electrical equipment as soon as possible. After doing a good job of protection action analysis records and operational analysis records, including: job analysis, professional analysis and evaluation, conclusions and so on. Where a protective device is not correct action, promptly organize on-site inspection and analysis, find out the reasons, put forward preventive measures to avoid the occurrence of repetitive accidents.
5, to strengthen technical transformation
(1) For the DC system, DC voltage pulsation coefficient is large, multiple transistor and microcomputer protection work abnormal phenomenon, the original silicon rectifier device into a rectified output AC components, high reliability, integrated circuit silicon rectifier charging Device. For the frequent occurrence of DC power loss in rainy and wet weather, the easy-aging terminal block in the outdoor terminal box of booster station is replaced with a ceramic terminal to improve the secondary insulation level. Second, check and rectify the secondary circuit, so that its control, protection, signal, closing and thermal circuit gradually separated. In the switch room installation of fuses shunt switch box, easy to straight
DC Motor
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