Discussion on Installation Technology of Substation Electrical Equipment

The substation is an important part of the power system, and its operation quality is related to the operation safety of the entire transmission line and the safety of people’s electricity consumption. The electrical equipment is the key to ensure the safe and stable operation of the substation. The relevant personnel need to scientifically grasp the installation technical points of the entire electrical equipment and continuously improve the technical level of installation.

With the continuous development and progress of society, the construction scale and number of substations have continued to rise, while at the same time, the number of various types of electrical equipment is also gradually increasing, and its installation quality is related to the quality and safety of the operation of the entire substation. Therefore, in order to ensure the stable operation of the substation, it is necessary to pay enough attention to the technical points and processes of the installation of electrical equipment and standardize the work of each link.

Substation electrical equipment

There are many electrical equipment involved in substations, such as main transformers, circuit breakers, cable lines, etc. Among them, the main transformer is a very important electrical equipment in the substation and the core equipment necessary for power transmission; circuit breakers can ensure the timely start and closing of various types of equipment, so that the power supply of the equipment with failure problems can be closed in time, which does not cause the entire circuit system Impact; Cables and busbars are unavailable power equipment and important equipment for normal power transmission. No matter which electrical equipment is missing, the substation cannot run smoothly. With the continuous improvement of people’s material living standards, the demand for electricity has gradually expanded, the load of various electrical equipment has increased, and various quality problems have gradually emerged during the operation. Therefore, relevant personnel must strengthen Quality control of electrical equipment in substations.

Transformer construction process

Transformer is an important equipment that needs to be installed in the substation, and its quality is related to the overall operation safety of the substation. From the perspective of the appearance characteristics of the transformer, it is large and heavy. In order to lift it to the designated area, some auxiliary equipment such as rails and jacks need to be used when lifting. Moreover, in the process of hoisting, corresponding protective measures should be taken to prevent the transformer from being knocked and damaging its performance. Therefore, in the actual lifting, the stability of the center of gravity must be ensured, and the equipment must be lifted slowly and easily to avoid damage to the equipment. In addition, carefully check the position of the oil level observation hole to see if it meets the standard. After the equipment reaches the construction site, it must be carefully checked, and only qualified products can be installed. In this process, the following work needs to be done: (1) Before the formal disassembly, you want to lift the oil tank of the transformer; (2) Dismantle the transformer according to the standard specification process, for the sake of better restoration in the future, Relevant personnel need to record all steps of dismantling when they are actually dismantling. (3) Strictly follow the steps of dismantling to restore, do not miss any small accessories in the transformer. At the same time, in order to ensure the firmness of the bolt connection, when the bolt is used, the bolts need to be connected, installed, and tightened in order. (4) Installation of accessories on the transformer. When installing accessories, in order to avoid the main body of the transformer being exposed to the air, allowing moisture to enter the transformer and affecting the performance of the internal equipment, the time when the equipment is exposed to the air should be controlled, generally not more than 8h to reach the specified time. Seal with plastic film and flush the pipeline with insulating oil of up to standard quality. At the same time, the valve should be carefully checked and cleaned with clean gauze to make the valve more flexible. In addition, the connection position of the valve and the bolt should be well sealed to avoid problems such as loosening. When installing accessories, in order to make the transformer oil filling and power transmission work smoothly, the initial parameters of the accessories must be set. Especially for some large-scale transformers, vacuum drying is a very critical part. Before the actual operation, the isolation valves of the accessories and the oil tank are opened, while the oil storage cabinet and the body valve are closed.

Construction Technology of Transformer

Because the transformer is large and heavy, it is lifted in the same way as the transformer during transportation. The installation method adopts the method of distribution and transportation. The installation of transformers needs to be installed in strict accordance with the number, and it is necessary to ensure that no oxide layer appears at the connection of each component. In order to prevent the appearance of the oxide layer when installing each component, it is necessary to apply a separation layer to the attachment connection. After completing the installation task of the transformer, the verticality should be adjusted so that it is in a standard position, and the transformer should be fixed with bolts. In addition, in order to ensure that the transformer shell is not charged, its base must be grounded. In the process of grounding installation, it is necessary to control the cross section of the grounding wire so that it meets the requirements of the design specifications. It should also be noted that, when installing the graded insulation transformer, the ground lead terminal of the winding must be firmly connected to ensure its good conduction performance.

Construction technology of cable

Before the actual laying of the cable, the purpose of each cable should be divided and installed in order in strict accordance with the requirements. At the same time, it is necessary to formulate a corresponding construction plan based on the actual situation of the substation and the direction of the cable trench. Pay attention to the following issues when laying the cable: (1) To ensure the quality and safety of the cable. When the cable enters the construction site, in order to ensure that the quality and quantity of the cable meet the construction requirements, in addition to a comprehensive inspection of the cable type and specifications, the relevant personnel must also use a 1000V megohmmeter to test its insulation performance. At the same time, it is also necessary to make an indication board containing relevant information such as model number and voltage for the cable. (2) Determine the distribution of cable supports according to the voltage level. (3) In order to lay the cable line to meet the requirements of the standard, it is necessary to check the parameters such as the length and thickness of the cable line, and clarify the laying sequence of the cable line. At the same time, it is necessary to design a cross-sectional view of the cable, and the content of the cable trench, bracket position and other standard numbers in the figure. (4) When laying concretely, it is necessary to ensure the similarity of the type and diameter of the cable laying on the same level. In order to improve the quality and safety of the laying, the arrangement of the cable wires in the cable trench must be neat, and there must be no crossover problems. Therefore, when determining the laying path, the relevant personnel should conduct a comprehensive inspection of the arrangement of the lines in the cable trench, especially the cable lines at the intersection.

In short, the substation is a very important infrastructure in my country, and the installation quality of electrical equipment is related to the operation quality and safety of the entire substation. Therefore, relevant personnel should pay enough attention to the installation of electrical equipment in substations, fully implement the installation work in all links, install and construct in strict accordance with the requirements of relevant technical standards, and improve the installation quality and level of electrical equipment in substations.