Lightning protection measures for diesel generator sets?

The lightning protection mode of the generator should be determined mainly according to the size of the generator capacity, the strength of the local lightning activity and the requirements for the reliability of power supply. Theory and practice have proved that the generator that is connected with the overhead transmission line after the transformer, as long as the transformer is reliably protected, generally does not need to take lightning protection measures for the generator, in the multi-mine area, the particularly important generator without overhead direct wiring, in order to prevent the lightning wave of the high-voltage side of the transformer from endangering the insulation of the generator through the transformer, it is advisable to install a group of magnetic blowing arresters on the outgoing line of the generator. The generator directly connected to the overhead distribution line must be protected by lightning, and different lightning protection measures should be taken for the generator insulation according to the provisions of the national standard design specifications.

For a direct motor with a single capacity of 300 1500kw, it is advisable to use protective wiring for overvoltage protection. For high-voltage direct motors with a single capacity of 300kw and below, according to the specific situation and operating experience, only a group of lightning arresters and capacitors are installed at the entrance of the road, and protective gaps are installed on the poles near the households or the insulator iron feet are grounded.

The lightning arrester used to protect the high-voltage rotating machine generally adopts a magnetic blowing arrester, and the arrester should be installed close to the generator. In general, the arrester can be installed at the outlet of the motor; If there are no more than two generators connected to each group of buses, or the capacity of a single unit does not exceed 500kw, and the distance from the arrester does not exceed 50m, the arrester can also be installed on each group of buses.

When the neutral point of the direct distribution motor can be drawn out and is not directly grounded, a magnetic blowing or ordinary valve-type arrester should be installed at the neutral point.

1. The operation of the generator set must be carried out by personnel who master the safety operation procedures and are familiar with the structure of the unit. New or newly overhauled generator sets should be run for 60 hours according to the regulations, and the necessary maintenance should be done.

2. Before the new generator set or the generator set that has not been in operation for a long time is put into normal operation, it must go through strict inspection, mainly check the winding insulation, wiring, etc., and if there is any inconsistency, carry out necessary treatment.

3. After the diesel engine starts, the speed should be slowly increased, and the no-load operation from low speed to rated speed can be carried out under the premise of checking and confirming that everything is in good condition. When running at no load, focus on checking the oil pressure, whether there is abnormal noise, excitation current, three-phase voltage change, etc., if there is any abnormal situation - should be stopped immediately for inspection. After ascertaining the situation, start again.

If everything is in order, it is ready for operation. The operator should closely monitor the changes of the instrument on the control screen, whether it is within the permitted range, and make corresponding adjustments.

4. During operation, the operator should keep a safe distance from the live equipment and wear labor protection equipment. If there is a power failure, the branch switch should be disconnected first, and then the main switch should be disconnected, and then the four-pole double-throw knife switch should be switched. When sending electricity, the order is reversed.

Normal shutdown should first unload part of the load, then break the main switch, and finally turn off the diesel engine, it is not allowed not to pull off the main switch, and the diesel engine will be turned off and the power will be cut off by itself. After the shutdown, the unit is routinely inspected, and the operation status (work diary) is recorded.

5. In case of electric shock, the power switch should be cut off quickly, or the power supply should be quickly cut off or disconnected from the power supply with an insulating device. Then the rescue was carried out and the doctor was called to the scene to rescue him. In the event of a flood of electrical equipment, the power supply should be cut off immediately, and the local power supply station should be reported to the local power supply, and then the fire should be extinguished.

Dry fire extinguishers, carbon dioxide fire extinguishers, etc. should be used to extinguish live equipment, and water is not allowed.

The high voltage generated by the strong movement of the atmosphere can be instantaneously discharged through the power line or antenna (mainly long wire) of electrical equipment, resulting in internal breakdown (high-voltage damage) or melting (power damage) of electronic components in electrical equipment, and finally causing permanent damage to electrical equipment

And the strong magnetic field caused by this high voltage and strong discharge sometimes produces high voltage in the transformer of some electrical appliances, burning electronic components Good electrical appliance manufacturers will do the corresponding lightning protection measures when designing circuits and designing printed circuit boards, high-rise buildings must be equipped with lightning rods, and do not use electrical appliances when thundering

TV: Watching TV during thunder, the image is very unstable, the interference is large, and the mood is always a little scared, worried about the plane crashing and people dying, is this possible?

In fact, as long as the outdoor antenna is not connected, the TV is used indoors, and there is generally no need to be frightened, because although the thunder and lightning are powerful, before entering the room, the thunderstorm clouds have already discharged with the earth. In the short discharge process, most of its huge energy is converted into heat, light and other energy, so it will not cause harm.

Usually when lightning strikes, when watching TV during the event, most of the interference on the screen and in the accompanying sound is the radiant energy of lightning, not the energy of induction or discharge. This kind of radiant energy generally does not damage the TV.

However, it must be emphasized that it is dangerous to use an outdoor antenna or to watch television outdoors during a thunderstorm, and lightning protection measures must be taken if it is monitored.

Electric light: When thunder, the voltage becomes very large instantly, which will cause the electric light to go off and cause a disaster. But there is usually no need to turn off the lights, because the voltage increases, and the work of the substation is suspended at the same time, that is, the power is out, so the lights at home will automatically turn off the power even if they are not turned off, which is safe.

Computer: The voltage of the powerful lightning will cause the semiconductor integrated circuit to be broken down instantaneously and lose its original polarity, so the integrated circuit will be damaged, the computer is composed of a large number of integrated circuits, and if the integrated circuit is broken, the computer will be broken.

In addition, the voltage of thunder is very high, and the instantaneous high-voltage discharge will cause the nitrogen in the air to be broken down and burned, which is to release a lot of heat, and it will also burn the computer.

Furthermore, the type of lightning belongs to static electricity, and those who know the circuit know that static electricity is the first killer of integrated circuits.

Thunder has the opportunity to cause the wire to produce instantaneous high voltage At this time, the high voltage may break through the electrical components, and the serious one may cause **, and the slight one will also burn the fuse tube So if it is an area with more serious thunder, sometimes even the electric lights must be turned off, because it may suddenly burst on, hurting people nearby Of course, if the clouds are very high, it will have no effect Generally, those thunders that sound more scary, the clouds are low, and they must be turned off at this time!