Main hazards of icing on high-voltage transmission line towers:
(1) The line icing is too thick, the wind area of the conductor increases, the conductor load is easy to break, and the mechanical load of the tower is easy to break.
(2) The insulation performance of insulators is greatly reduced after icing, which is easy to cause single-phase grounding or interphase short circuit. It is particularly difficult to find the fault point and recover operation after pole fall, wire break, short circuit and other faults occur in the line icing. Therefore, it is particularly important to observe the icing thickness, melt and deice in time.
The ice melting method is powered off.
1. Fix the output line or nearby line of the generator ice melting method power station, short circuit the other end to the other end that needs ice melting, connect the power supply of the generator, turn on the generator, slowly increase the current, and the conductor bears the heating current to melt the ice and snow. Advantages of fixed engine powered ice melting method
(1) Due to the large power of the generator, it can provide any current and can be used at all levels;
(2) Local materials, simple operation, just a few meters short; Even if the power line needs to be reconnected, the safety and technology can be easily solved due to the low output voltage of the generator. Disadvantages of fixed engine powered ice melting method:
(3) Only the lines used to connect with the power station and conveniently connect with the power station;
(4) The ice melting line needs to be powered off, and the generator cannot supply power during ice melting.
(1) The line icing is too thick, the wind area of the conductor increases, the conductor load is easy to break, and the mechanical load of the tower is easy to break.
(2) The insulation performance of insulators is greatly reduced after icing, which is easy to cause single-phase grounding or interphase short circuit. It is particularly difficult to find the fault point and recover operation after pole fall, wire break, short circuit and other faults occur in the line icing. Therefore, it is particularly important to observe the icing thickness, melt and deice in time.
The ice melting method is powered off.
1. Fix the output line or nearby line of the generator ice melting method power station, short circuit the other end to the other end that needs ice melting, connect the power supply of the generator, turn on the generator, slowly increase the current, and the conductor bears the heating current to melt the ice and snow. Advantages of fixed engine powered ice melting method
(1) Due to the large power of the generator, it can provide any current and can be used at all levels;
(2) Local materials, simple operation, just a few meters short; Even if the power line needs to be reconnected, the safety and technology can be easily solved due to the low output voltage of the generator. Disadvantages of fixed engine powered ice melting method:
(3) Only the lines used to connect with the power station and conveniently connect with the power station;
(4) The ice melting line needs to be powered off, and the generator cannot supply power during ice melting.
2. High voltage transmission line tower system transformer ice melting method system electric transformer ice melting method is to use the 400V transformer in the system to provide power by the system, short the other end, open other branch lines, connect the transformer after ice melting, and then close the switch line with 400V voltage to melt the conductor. Advantages of electric depressurization method in ice melting system
(1) Local materials, simple operation;
(2) The 400V voltage needs to be reconnected to the line to solve the safety and technical problems.
Deficiencies in the depressurization method of ice melting system
(1) It needs to be powered by the system;
(2) As the voltage provided by the transformer is constant, it needs to be calculated. According to the capacity of the transformer, the sectional area and distance of the short circuited conductor, the current required for conductor heating and the short circuit current that the transformer can provide, the current required for conductor heating and the short circuit current that the transformer can provide, the current required for conductor heating and the short circuit current that the transformer can provide should be calculated.
(3) Power off the ice melting line,
3. Transformer (vehicle) ice melting method The transformer (vehicle) ice melting method is the same as the system electric melting pressure ice melting method, with similar advantages and disadvantages. The difference is that the transformer (vehicle) ice melting method is installed on the vehicle, which makes it easier to find the system power point and find a better location to access the ice melting line. However, the transformer (vehicle) ice melting method is a better method, but the transformer (vehicle) ice melting method is a better method, It is a relatively high ice melting method with the same advantages and disadvantages, but the transformer (vehicle) ice melting method is a relatively high ice melting method, while the transformer (vehicle) ice melting method, the transformer (vehicle) ice melting method, the transformer (vehicle) ice melting method, the transformer (vehicle) ice melting method and the ice melting method The utility model can also connect the adjustable resistor, the silicon controlled voltage regulator, the silicon controlled voltage regulator, the silicon controlled rectifier, etc. on the 400V side to make the voltage adjustable, It is more convenient to adapt to various ice melting lines.
4. Generator (car) ice melting method The generator car ice melting method is to put the generator into the car, send the generator to the most appropriate distance, short the other end of the ice melting line, open the contact network of other branch lines, connect the power supply of the generator, slowly increase the current to the heating current that the wire can withstand, so that the ice and snow can melt.
Advantages of motor (vehicle) ice melting method:
(1) The short contact and current input point of the ice melting circuit can be arbitrarily selected, and the generator output voltage is low, which is easy to solve safely and technically;
(2) The current can be adjusted at will. As long as the generator capacity is sufficient, all lines can be adjusted.
Disadvantages of generator set (vehicle) ice melting method:
(1) The generator (vehicle) is expensive, and the ice melting current required by large capacity and high voltage lines is large, and the power required by the generator (vehicle) is large and expensive.
(2) Except for ice melting, the generator (automobile) has no other use and is inefficient.
Problems needing attention in ice electric melting
(1) Low voltage short circuit protection device must be installed at the outlet of generator or distribution transformer providing ice melting current for the line to ensure the safety of generator or distribution transformer.
(2) The connecting wire and short wire of the ice melting line shall not be smaller than the diameter of the ice melting line.
(3) The ice melting current of the line shall be less than the rated current of the generator or distribution transformer.
(4) It must be ensured that the melting line area is not empty.
(5) Pay attention to the linear vibration during ice melting. When the ice layer is less than 5cm, the ice melting should be carried out quickly. When the ice layer is more than 8cm thick, the oscillation of the ice line will increase correspondingly when the ice layer falls off, and the vibration of the overhead line will increase to about 20cm. The tension of the overhead line will cause the short circuit of the overhead line.
(6) The ice melting should be avoided too fast, and the icing should fall slowly, and the ice can be melted at intervals ().
(7) Arrange personnel to patrol along the line during ice melting, and take measures to prevent ice from injuring people during ice melting.
(8) If the ice melting line crosses the highway, the injected current will prohibit vehicles and pedestrians from passing through, so as to prevent vehicles and people from being injured by falling ice.
(9) Observation and measurement shall be done well during ice melting, and the operation shall be stopped immediately in case of any abnormality.
(10) Before ice melting, materials and protective equipment shall be prepared. Grounding wires, insulating gloves, electroscope, parallel groove clamps, insulated conductors (the section shall be determined according to the ice melting line), clip on ammeters, voltmeters (multimeters), low-voltage openings with protection, thermometers (or imagers), safety belts, helmets, foot buckles (pedals), etc. shall be provided. In order to save lapping time, a new type of C-type parallel groove clamp is better used.
Ice melting method Transfer load Ice melting method refers to combining the load of more than two circuits of lines into one line for power supply, increasing the line current to make the conductor warm and melt ice. This method can melt ice as long as conditions are met. This method can make the conductor warm and melt ice as long as conditions are met. Attention should be paid to the problems of ice transfer and melting:
1. In the process of ice melting, first change the relay protection of the ice melting line to prevent the line from tripping.
2. The line loss after the current is loaded shall be considered. It is necessary to make the line conductor warm up and melt ice reliably, and to keep the user voltage within the qualified range. The voltage quality shall not be reduced due to the melting ice.
3. During the ice melting process, observation and measurement shall be done well. If any abnormality is found, the operation shall be stopped immediately.
Manual deicing is mainly used for short distance, partial or partial ice melting of 35KV and 10KV lines, such as ice melting by bamboo pole hitting, ice melting by rope swinging, ice melting by pulley moving, etc. Bamboo hitting ice melting is to directly hit the conductor with a bamboo pole, and the conductor shakes and the ice and snow fall off. The advantage of bamboo hitting ice melting is that it does not need to go on the pole, so the safety risk is small, the technical content is low, and the safety risk is small. You can directly hit the conductor with a bamboo pole, and the conductor will fall off after vibration. The safety risk is small, the technical content is low, and the safety hazard is small. Rope swing ice melting means that the rope is sheathed on the conductor, sliding longitudinally and swinging transversely, so that the conductor will overturn and fall off. It has the advantages of no pole, low safety risk, low technical content, mass multi span simultaneous operation, and can not be used for lines with too high ground distance, mainly 10KV and 35KV lines. Sliding ice melting refers to the use of pulleys, pulleys, step boards, etc. to fix people on electric wires. When moving along the line, use wooden mallets, rubber mallets, etc. to knock the ice to make the ice fall off. When moving along the line, the pulley is mainly used to fix people on electric wires with bamboo poles, pulleys, step boards, etc. When moving along the line, use wooden mallets, rubber mallets, etc. to knock the ice to make the ice fall off. During the ice melting process, use wooden sticks, pulleys, step boards, etc. to fix people on electric wires, Move the ice block along the line to make it slide to melt the ice, make it slide to melt the ice, and the pulley moves to melt the ice.
HENGFENGYOU ELECTRIC GROUP, is an electrical enterprise with transmission and distribution industry as its main business, integrating product research and development, manufacturing and trade. Designated suppliers for the world's top 500 enterprises .Its main products include power transformers, medium and low voltage switchgear, distribution panel ,circuit breakers, transmission tower ,Cable and other power distribution equipment , HENGFENGYOU ELECTRIC GROUP has been working hard to provide the best transmission, distribution solutions for users all over the world. www.transmission-tower.com ; sales@hengfengyou.com ； WhatsApp：+86158 5325 2696（Jack）