How can the transmission line see the direction of transmission Is there a clear mark

There should be none, because there is no need.

I don't know what major the landlord is studying.

First of all, the vast majority of them are AC transmission, and the voltage and current are constantly changing, and there is no direction to talk about.

Secondly, the direction of transmission refers to the direction of transmission of electric energy, that is, power.

General power lines are divided into liaison lines and feeders.

The direction of power on the contact line is also not necessarily, and the direction of active and reactive power may also be inconsistent. There is a normal state, but there is no certainty. The above issues involve the power flow distribution of the power system, which is something to be considered in dispatching.

Nowadays, there are advanced measuring equipment and large computers, and there are simulations in the dispatching area. How to transmit electricity on the power line is clear.

Therefore, there is no need to indicate on the actual line or tower on the site.

The power transmission of the feeder is generally fixed, and the circuit breakers at both ends must be disconnected to overhaul this line.

To put it simply, it doesn't make sense to mark the direction of transmission on the actual transmission line. What do you think you can do even if you know? There is no way to operate it on the spot.

The above is my own reasoning, my specialty is power systems. But I'm not sure about that. The landlord can ask the teacher for advice.

Or it's better to go to the line class of the local power supply bureau and ask, everything is clear.

Supplement: The direction of power transmission at any time can be known through monitoring, but if you stand under the transmission line and look at it, it is estimated that you will not be able to find the mark.

The direction of transmission cannot be seen from the transmission line.

In the power system, the transmission line connects two substations and can transmit electricity in both directions. In particular, the "connection" line between the two substations may supply power from A to B at one time, and from B to A at that time.

Facing the direction of power reception, from left to right, they are arranged in A, B, and C. The three-phase four-wire is arranged according to A, B, O, C.

Look at it with electric current.

Method 1: You can directly use the ammeter to see it.

Method 2: You can use the magnetic field generated by the electric current.

There are several scenarios for the consequences of the wrong phase sequence connection of a high-voltage line:

1. The investment of a single line, whether the phase sequence is right or wrong, has no impact on the line itself;

2. When the line is connected to the substation, it will not have any impact on the single equipment in the interval, such as circuit breakers, isolation switches, lightning arresters, etc.;

3. The reactive power compensation device has very strict requirements for the input A, B, and C phase sequences. If the phase sequence is wrong, or the phase of current sampling and voltage sampling are in the same phase, it will cause inaccurate detection of power factor, and there will be a situation that cannot be automatically put in, and there will also be overcompensation.

4. If another line is connected to parallel operation through the distribution interval, under the premise that there is no nuclear phase, the phase sequence is wrong, and the access will lead to a short circuit between the phases, and then there will be a major accident, and the protection will definitely jump, so the line is put into operation to the substation, and the nuclear phase work is very important.

A brain cell "friend's opinion" a first upstairs said that a major accident would not happen, but tripping was there. Because now the protection is comprehensive. If it is short-circuited, it will trip Lima".

I don't think it's appropriate for the following reasons:

In the event of a short circuit, the current in the short circuit increases greatly due to the decrease in the impedance of the power supply circuit and the transient process in the event of a sudden short circuit, which may exceed the rated current of the circuit many times. The magnitude of the short-circuit current depends on the electrical distance of the short-circuit point from the power supply, for example, when a short circuit occurs at the generator end, the maximum instantaneous value of the short-circuit current flowing through the generator can reach 10 15 times the rated current of the generator, and in a large-capacity power system, the short-circuit current can be as high as tens of thousands of amperes.

Hazards of short-circuit currents.

Short-circuit currents will cause the following serious consequences: short-circuit currents often have arcing, which can not only burn out the faulty components themselves, but also burn out the surrounding equipment and injure the surrounding personnel. When the huge short-circuit current passes through the conductor, on the one hand, it will cause a large amount of heat to the conductor, causing the conductor to overheat or even melt, and the insulation is damaged; On the other hand, the huge short-circuit current will also generate a large electrodynamic force acting on the conductor, causing the conductor to deform or damage.

Although the protection device of the current power equipment is relatively complete, and the protection action time is very short, but in the period of protection action, the instantaneous huge short-circuit circuit is enough to cause great damage to the power equipment in the circuit, in this process, the protection device can only play a role in quickly cutting off the short-circuit current, reducing the duration of the short-circuit current, reducing the loss caused by the short-circuit, and can not completely avoid the occurrence of the accident of damaging the equipment, so it is not wrong to say that a major accident occurs.

There is no certain rule, because in order to ensure the three-phase balance in the process of some lines, a commutation tower is also set up to change the phase.

There is no color code, no signage, no way to judge. Because there is no provision for the A phase to the left facing the direction of the incoming call? It is still the A phase on the left facing the load direction.

In addition, long-distance high-voltage transmission lines (such as 110kV), in order to ensure three-phase balance, a commutation tower should be set up to change the phase.

Answer: On the tower of the transmission line, each base tower must have a line number, line name, and pole number, that is, the "No. 3" sign; Transposition towers, bifurcation towers and terminal towers should have phase sequence signs that conform to the actual line; Double-loop and multi-loop parallel sections should also have color signs to prevent mistaken boarding of the tower; The high tower shall be equipped with aviation obstacle signs in accordance with the regulations of the aviation department.

Three Gorges University (Laogeshui Academy, Wushui-Yichang).

School of Mechanical and Materials Mechanical Design, Manufacturing and Automation (Transmission Line Engineering) Northeast Electric Power Institute Civil Engineering It seems that there is also a Transmission Line Engineering Direction, I am the three major Transmission 1482 graduated Hehe! So I still know a little bit about Yichang.

Northeast Electric Power University, Nanjing Institute of Technology. At present, there is no such major in the country, but it is affiliated with other majors, such as Northeast Electric Power University.

Transmission is realized by using a transformer to boost the power generated by the generator, and then connecting it to the transmission line through control equipment such as circuit breakers. According to the structural form, transmission lines are divided into overhead transmission lines and cable lines. Overhead transmission lines are composed of line towers, conductors, insulators, line fittings, pull wires, tower foundations, grounding devices, etc., and are erected on the ground.

According to the nature of the transmitted current, power transmission is divided into AC transmission and DC transmission. In the 80s of the 19th century, direct current transmission was first successfully achieved. However, due to the difficulty of continuing to increase the voltage of DC transmission under the technical conditions at that time, the transmission capacity and efficiency were limited.

At the end of the 19th century, direct current transmission was gradually replaced by alternating current transmission. The success of AC transmission ushered in a new era of electrified society in the 20th century.

China Three Gorges University (Electrical Engineering and Automation), Shaoyang University (Electrical Engineering and Automation), North China Electric Power, Northeast Electric Power.

Nanjing Institute of Technology has, the school in general, belongs to the power system and its automation.

China Three Gorges University, Northeast Electric Power Institute.

There are only old brands that the Three Gorges University has.

Given that your bai problem can only be rough

Slightly answered, there is too much content involved, you can determine which is the square weight pile and which is the center pile through the pitch and high version difference of the drawing dao, now the general retest is directly carrying the GPS positioning, if you use the total station, don't say it, if it's a theodolite, I won't write the symbol of the formula on this, you can look at the book of measurement, the root open is given on the construction drawings, all are half a root open, you can multiply the root number 2 to calculate the half diagonal to find out the center of the pit, and then the radius of the pit mouth is rounded, I'm talking about the square flat leg foundation, if it is a high and low leg to calculate his height difference to the base surface, if it is rectangular you can do a 45 degree corner pile, but this is more troublesome, directly on the center pile is the same, this is the anchor bolt type, inserted angle steel multiple lower fulcrum on the top angle and slope ratio, I will not play the symbol of the formula on this, if you do not understand or can not find the relevant textbooks, you can ask the contact, pure hand play, the content is not fine, forget to forgive.

If you are a construction unit, then the center pile is designed to be nailed, when the pile is delivered, you will be told that you are from the center of a base pile to the other base of this line, any point can be your direction pile, the root should be designed to give, know that the root can be divided into pits.

The problem is a bit complicated, go find the relevant books.

Ultra-high voltage transmission lines generally use steel strands. There is no set distance between the two towers. The distance from the ground at the lowest point of the vertical curvature of the line of sight. I don't know the exact data.

This is a very big and unprofessional question.

Transmission line engineering majors can be registered electrical engineers, registered structural engineers, registered constructors, etc. The major of transmission line engineering cultivates senior engineering and technical talents who master the basic theories and basic knowledge of the transmission engineering discipline, obtain the basic training of engineers, and have certain practical ability and innovative spirit.

Through the study of this major, students can obtain the basic knowledge of mechanics, electrical engineering, and transmission engineering, master the professional knowledge and professional skills of transmission engineering, and receive good scientific thinking and experimental skills training.

Graduates have the ability to engage in the planning, design, research and development, construction and management of transmission engineering projects, and can be engaged in technical or management work in the design, research, construction, education, management, investment, development and other departments of transmission line design, transmission line construction, transmission line operation and maintenance.

1. Circuit design: Registered Electrical Engineer (Power Transmission), Registered Structural Engineer;

2. Line construction: construction engineering back to the division, safety engineering engineer (power transmission),;

3. Line construction supervision: supervision engineer (mechanical and electrical);

3. Operation and maintenance: mechanical and electrical engineer (professional title evaluation).

4. Technical and economic: cost engineer.

It's good to get an electrical builder, and it's important for you to work in the power system in the future, which may require work experience.

I didn't participate in the work and took the English level The most important thing is hehe.

The basic process of electricity transmission is to create conditions for the transmission of electromagnetic energy in the direction of the transmission line. The transmission capacity of the line is governed by the various laws of the electromagnetic field and the circuit. With the earth potential as the reference point (zero potential), the line conductors are subjected to a high voltage applied by the power supply, which is called the transmission voltage.

The maximum transmission capacity of the transmission line determined after comprehensive consideration of technical, economic and other factors is called the transmission capacity of the line. The transmission capacity is roughly proportional to the square of the transmission voltage. Therefore, increasing the transmission voltage is the main technical means to achieve large-capacity or long-distance transmission, and it is also the main indicator of the development level of transmission technology.

From the perspective of the development process, the transmission voltage level increases by about two times. When the power generation is increased to about 4 times, a new and higher voltage level appears. Transmission lines of 35 220 kV are usually called high-voltage lines (HV), transmission lines of 330 750kV are called ultra-high voltage lines (EHV), and transmission lines above 750 kV are called ultra-high voltage lines (UHV).

Generally speaking, the larger the transmission capacity, the higher the voltage level of the line. The use of ultra-high voltage transmission can effectively reduce line loss, reduce the unit cost of the line, occupy less arable land, and make full use of the line corridor. China's first "Northwest 750kV Power Transmission and Transformation Demonstration Project", the world's highest altitude "Northwest 750kV Power Transmission and Transformation Demonstration Project", Qinghai Guanting to Gansu Lanzhou East 750kV Power Transmission and Transformation Project, was officially put into operation on September 26, 2005.

1000kV AC UHV test demonstration project" - Jindongnan-Nanyang-Jingmen 1000kV transmission line project, started construction on August 19, 2006. The project starts from the 1000kV substation in the southeast of Shanxi, passes through the Nanyang 1000kV switch station, and ends at the Jingmen 1000kv substation, with a total length of the line path. In addition, there are 500kV HVDC transmission lines and 800kV UHVDC transmission demonstration projects.

The 500kV mainly includes Gezhouba--- Shanghai Nanqiao Line, Tianshengqiao--- Guangzhou Line, Guizhou--- Guangdong Line, Three Gorges --- Guangdong Line. Xiangjiaba-Shanghai 800kV UHV DC Transmission Demonstration Project is the first UHVDC Transmission Demonstration Project in China. The project is independently developed, designed, constructed and operated by China, and is currently the world's highest DC voltage and most advanced DC transmission project.

Transmission line equipment exceeds the design and operation specification standards, that isDefects in transmission lines.

Transmission line defects include the following:Defects in the line bodyDefects in ancillary facilitieswithExternal hidden defectsThree categories.

Ontological defects:

It refers to the defects of the components, accessories and parts that make up the line body, including foundations, towers, ground wires, insulators, fittings, grounding devices, etc.

Defects in ancillary facilities

External hidden defects

It refers to the situation that changes in the external environment have posed a potential threat to the safe operation of the line (such as the impact of new houses, planting trees and bamboos, piling up objects, taking soil, and offline construction vehicles in the protected area).