When it comes to the power system, while we think about the huge production benefits and living convenience it brings, we also pay great attention to its power and safety, after all, electricity is known as the "electric tiger". In the daily use of power transformers, "insulation" is the core key to ensuring their safe and stable operation, which directly determines the service life and operational reliability of transformers, and is also an important line of defense to avoid electrical accidents. Whether it is the commonly used 2500 kva transformer or the oil filled distribution transformers widely used in the power distribution field, their insulation performance is one of the core indicators to measure product quality. As a professional transformer manufacturer, JINSHANMEN TECHNOLOGY CO., LTD always adheres to high standards in the insulation design and production of various transformers, providing reliable power transmission and distribution equipment for customers around the world.
JINSHANMEN TECHNOLOGY CO., LTD mainly produces oil immersed power transformers, dry-type power transformers, oil immersed three-dimensional coiled power transformers, dry-type three-dimensional coiled power transformers, mining explosion-proof dry-type transformers, mining explosion-proof mobile substations, amorphous alloy power transformers, on load capacity regulating power transformers, locomotive dry-type transformers, as well as prefabricated substations, modular substations, wind energy box type substations, high and low voltage switchgear and other transmission and distribution equipment. With mature insulation technology, it endows 2500 kva transformer and oil filled distribution transformers with excellent insulation performance to meet the needs of different scenarios.
I. Basic Concepts of Insulation
Insulation is a physics term, referring to a safety measure that uses non-conductive substances to isolate or wrap charged bodies to protect against electric shock. The insulation of power transformers is to prevent current leakage and breakdown, ensuring the electrical safety and reliability of transformers. It involves the insulation between transformer components such as windings and iron cores and the ground, between windings of different phases, and between different voltage levels. For 2500 kva transformer, due to its moderate capacity and wide application scenarios, good insulation performance can effectively avoid leakage, short circuit and other problems during operation; as the core equipment of the power distribution system, the insulation system of oil filled distribution transformers is directly related to the stable operation of the power distribution network, avoiding large-area power outages caused by insulation failure.
II. Types of Insulation
The insulation of power transformers is divided into full insulation and graded insulation. Different types of insulation are suitable for transformers of different voltage levels and capacities, adapting to different application scenarios.
Full insulation means that the entire winding is insulated to the same level, with uniform insulation performance, suitable for small transformers and low-capacity application scenarios, which can provide comprehensive insulation protection and higher safety. The so-called graded insulation (also known as semi-insulation) means that the main insulation of the transformer winding near the center point is lower than that of the input side. The advantage of this insulation method is that it can reduce the size of internal insulation, thereby reducing the volume of the entire transformer, lowering production costs, and being more economical.
Generally speaking, transformers used for voltage levels below 35KV all adopt full insulation structure, while graded insulation transformers are mainly used in large current grounding systems of power grids with voltage levels above 110kv. It is worth noting that most 2500 kva transformers adopt full insulation structure to ensure their safe and stable operation in medium and large-scale power consumption scenarios such as industry and commerce; oil filled distribution transformers will flexibly choose full insulation or graded insulation according to voltage levels and use environments, balancing safety and economy. In the production process, JINSHANMEN TECHNOLOGY CO., LTD will configure the most suitable insulation type for both transformers according to customer needs and application scenarios.
III. Insulation Structure
From the internal and external perspectives, the insulation of transformers can be divided into external insulation and internal insulation. The two cooperate with each other to form a complete insulation protection system, providing double protection for the safe operation of transformers. This structural design is also applicable to 2500 kva transformer and oil filled distribution transformers.
Internal insulation refers to the insulation between different electronic components inside the transformer oil tank, mainly including winding insulation, lead wire and tap changer insulation, etc. These insulation parts are sealed and protected by the oil tank, basically not affected by external conditions such as atmosphere, pollution, humidity and foreign objects, and have stronger stability. Internal insulation is further divided into main insulation and longitudinal insulation: main insulation refers to the insulation between windings and the ground, between phases, and between windings of the same phase but different voltage levels. It is the most critical part of internal insulation of transformers, directly affecting the operational reliability and product cost of transformers; longitudinal insulation refers to the insulation between turns, layers and sections of the same winding, mainly used to prevent short circuits inside the winding.
External insulation refers to the insulation bushings and air insulation outside the transformer oil tank, including the external insulation of the insulation bushings themselves and the insulation of the air gap distance between the insulation bushings and between the insulation pipes and the ground. The stability of external insulation is greatly affected by the environment. For example, humid, polluted, high-temperature and other environments will affect its insulation performance, but it has a certain natural recovery ability. In daily maintenance, it is only necessary to do a good job in cleaning and protection to ensure its normal work. For oil filled distribution transformers, the protection of external insulation is particularly important because most of them are installed outdoors and need to resist the erosion of various harsh environments; whether 2500 kva transformer is installed indoors or outdoors, it is necessary to regularly check the condition of external insulation to avoid failures caused by insulation aging and damage.
IV. Insulation Methods and Materials
The insulation methods and materials of power transformers directly determine their insulation performance. Different types of transformers will choose suitable insulation methods and materials according to their own characteristics. Among them, oil filled distribution transformers mainly adopt oil-immersed insulation, while 2500 kva transformer will flexibly choose oil-immersed insulation or dry-type insulation according to the use scenario. In the production process, JINSHANMEN TECHNOLOGY CO., LTD strictly selects insulation materials to ensure that the product insulation performance meets the standards.
From the perspective of insulation methods, there are mainly three types: oil-immersed insulation, dry-type insulation and gas insulation. Oil-immersed insulation is mainly used for oil-immersed transformers, which can ensure the normal operation of transformers under high voltage conditions, and has good moisture-proof, cooling, impact and arc-extinguishing performance. It is the core insulation method of oil filled distribution transformers, which can effectively extend the service life of transformers; dry-type insulation and gas insulation are mainly used for dry-type transformers. Dry-type insulation has the advantages of not being easy to get damp, not easy to catch fire and easy to maintain, but it is not suitable for high-voltage environments; gas insulation has low dielectric constant and good arc-extinguishing performance, but the cost is high and it is not easy to discharge gas in time, which is suitable for transformers in special scenarios.
From the perspective of insulation materials, they are mainly divided into solid materials and liquid materials. Solid materials include insulating paper, corrugated insulating paper, Denison paper, Nomex paper, etc. These materials have good thermal stability and moisture resistance, and are often used for insulation of windings, leads and other parts. They are important components of the insulation system of 2500 kva transformer and oil filled distribution transformers; liquid materials are mainly insulating oil, which has good insulation performance and cooling effect, and is the core material of oil-immersed insulation. It is necessary to regularly test and maintain the quality to avoid the insulation effect being affected by the deterioration of oil quality.
In addition, insulation materials can also be divided according to heat resistance grades. The common grades are A, E, B, F and H, each of which has a corresponding maximum allowable operating temperature: Grade A insulation allows a maximum temperature of 105 degrees, Grade E 120 degrees, Grade B 130 degrees, Grade F 155 degrees, and Grade H 180 degrees. According to the capacity, voltage level and use scenario of the transformer, JINSHANMEN TECHNOLOGY CO., LTD will select insulation materials with suitable heat resistance grades for 2500 kva transformer and oil filled distribution transformers to ensure that the transformer will not cause insulation aging due to high temperature during long-term operation.'
V. Insulation Faults and Countermeasures
During the long-term operation of transformers, affected by various factors, the insulation system may have faults. The most common ones are insulation aging and insulation dampness. Both faults will seriously affect the insulation performance of transformers, and even cause transformers to fail to operate normally. For 2500 kva transformer and oil filled distribution transformers, doing a good job in the prevention and treatment of insulation faults is the key to ensuring their long-term stable operation.
1. Insulation Aging
Transformer insulation aging is a complex and gradual process, referring to the insulation materials inside the transformer gradually losing their original mechanical strength and electrical insulation strength under the influence of various factors during long-term operation. The main causes of insulation aging include: improper moisture and heat insulation, chemical corrosion, long-term overload operation, transformer joint faults, electrical aging, pressure aging, etc.
To deal with transformer insulation aging, targeted prevention and treatment measures should be taken: regularly conduct insulation resistance testing and dielectric loss factor testing to timely detect signs of insulation aging; keep the transformer clean and dry to avoid moisture and pollution erosion; regularly change oil for inspection to ensure good insulation oil quality; maintain the cooling system to avoid long-term high-temperature operation of the transformer. For 2500 kva transformer and oil filled distribution transformers, JINSHANMEN TECHNOLOGY CO., LTD will provide professional maintenance suggestions to help customers extend the service life of the transformer insulation system.
2. Insulation Dampness
Insulation dampness of power transformers is likely to cause interlayer or interturn short circuits of transformers, causing serious damage to the power system and even triggering safety accidents. The main causes of insulation dampness of power transformers are: (1) insulation dampness caused by poor sealing of transformers; (2) insulation dampness caused by transformer quality problems; (3) insulation dampness during transformer transportation; (4) insulation dampness caused by transformer installation and maintenance; (5) insulation dampness caused by long-term disrepair and insulation aging of power transformers.
To solve the problem of insulation dampness, effective prevention and treatment measures should be taken: regularly inspect the transformer insulation materials and replace them in time if dampness is found; avoid moisture and oil pollution from entering the transformer during transportation and maintenance; pay attention to the operation method during use to avoid insulation dampness caused by improper operation. In particular, oil filled distribution transformers are more likely to be affected by humid environments because some of them are installed outdoors, so it is necessary to strengthen sealing protection and regular inspection; 2500 kva transformer also needs to strictly control the moisture-proof link during installation and maintenance to ensure that the insulation performance is not affected.
VI. Summary
The insulation system of transformers is the core to ensure their safe and stable operation. Whether it is 2500 kva transformer or oil filled distribution transformers, good insulation performance is the premise for their normal work. Understanding the basic concepts, types, structures, methods and materials of transformer insulation, as well as common insulation faults and countermeasures, can help us better maintain transformers, extend their service life, and avoid electrical accidents.
As a professional manufacturer of power transmission and distribution equipment, JINSHANMEN TECHNOLOGY CO., LTD always takes insulation performance as the core indicator of product quality. In the production process of 2500 kva transformer, oil filled distribution transformers and various other transformers, it strictly follows industry standards, selects high-quality insulation materials and advanced insulation technology, ensuring that each product can meet the needs of customers and providing reliable guarantee for the safe and stable operation of the global power system. The company mainly produces oil immersed power transformers, dry-type power transformers, oil immersed three-dimensional coiled power transformers, dry-type three-dimensional coiled power transformers, mining explosion-proof dry-type transformers, mining explosion-proof mobile substations, amorphous alloy power transformers, on load capacity regulating power transformers, locomotive dry-type transformers, as well as prefabricated substations, modular substations, wind energy box type substations, high and low voltage switchgear and other transmission and distribution equipment. Customers around the world are welcome to consult and cooperate.