\ BRIEF INTRODUCTION \
ABOUT THE SRN SERIES HIGH-TEMPERATURE RESISTANT OIL-IMMERSED TRANSFORMER-
CEEG's SRN high-temperature resistant oil-immersed power transformers are suitable for distribution networks with high load rates under high temperatures and places with shock load and continuous overload requirements. Specially built for high-end power supply and steel, coal, chemical, cement, paper, and metallurgy industries. Our SRN series oil-immersed power transformers served in many major industrial projects of famous enterprises like Guangzhou-Zhuhai Railway Co., Ltd., Beijing Shougang International Engineering Technology Co., Ltd., Guiyang Municipal Railway Road Co., Ltd., Heilongjiang Longmei Mining Group Co., Ltd., Guizhou Shuicheng Coal Industry, Heavy Coal Group, Lanzhou Railway Bureau, Liaoning Electric Power Co., Ltd., Shandong Luneng Materials Group Co., Ltd Division, Weiqiao Textile, Shanxi Electric Power Company, Shaanxi Electric Power Company, Northwest Power Grid Co., Ltd companies, etc.
\ FEATURES \ LOSS LOSS \ LOW NOISE \ STABLE & RELIABLE \
1. 7-stage temperature control technology system, which combined with the temperature field dinite element analysis, to ensure full play to the performance advantages of various insulation materials.
2. The insulation system is based on DuPont Nomex ® Insulation paper technology.
3. Low noise: unique noise reduction measures are adopted in different parts to ensure that the noise control is better than the national standards.
4. Low loss: The core is made of high-quality cold-rolled silicon steel sheet with high magnetic conductivity, using the Swiss core automatic laminating machine or longitudinal and transverse shearing, multi-stage full-slant seam automatic laminating, core tying using overall pressure and PET tape tying process, effectively reducing the no-load loss and no-load current of the transformer.
5. No leakage: The oil tank and oil storage cabinet have been tested for positive and negative pressure to ensure that there will be no oil leakage during normal operation. The components are installed with a flange groove structure, and all seals are made of high-quality once-formed acrylate rubber parts to prevent il-leakage.
6. Strong short circuit resistance: The transformer coils are calculated with reasonable ampere-turn balance and semi-rigid copper wire is used. The core claiming parts are calculated for strength and stiffness to meet the safety requirements of maximum short-circuit mechanical force. The winding pads are all densified and made of high-density rigid cardboard and adopted integra set & integral pressing to ensure the accuracy of assembly and the short-circuit resistance.
\ CERTIFICATED & QUALIFIED \
The oil-immersed power transformers have passed the test of the National Transformer Quality Supervision and Inspection Center, and all indicators have reached the advanced level of domestic and international products. The performance indicators meet the energy efficiency requirements of GB20052-2020 and also won the 3C, PCCC energy-saving certification, ISO-9001, ISO-45001, and ISO-14001 certificates.
CEEG's oil-immersed power transformers have been widely adopted in key projects by customers from all over the world. For example, they have been chosen to serve in the construction projects of Beijing China Coal Electric Co., Ltd., Shenhua United Construction Co., Ltd., and Chongqing Yuzhan Electric Co., Ltd.
\ 7- STEP TEMPERATURE CONTROL TECHNOLOGY \
The mature structure and technology of a traditional transformer shall be adopted as far as possible in the structure of a high-temperature liquid-immersed transformer, which retains the advantages of reliability, good manufacturability, and economy of the traditional transformer. The biggest difference between this
transformer and the traditional transformer is that the actual situation of the temperature field in the transformer is reasonably considered in the design, and the insulation materials with different temperature resistance grades are reasonably used according to the temperature distribution to form a hybrid insulation system. With the help of transformer temperature field simulation technology, the temperature distribution of the transformer (mainly winding and its vicinity) can be determined more accurately. According to different temperature ranges, different grades of insulating materials can be selected to give full play to
the high-temperature resistance characteristics of materials, and at the same time, it has a good economy.
The actual maximum oil temperature of this liquid-immersed transformer is set at 95 ºC, which ensures that the transformer has good safety, a thermal performance margin, and long expected life. For the temperature design of the whole transformer, we propose and implement the concept of a "seven-step temperature control technology" as the design principle, that is, gradually extends from the vicinity of the winding hot spot with the highest temperature to the external low-temperature area and divide it into five levels, and consider the short circuit and overload to form a seven-level thermal state for temperature control:
1/ Insulation material temperature control technology: different insulation materials shall be selected according to the temperature of different parts of the winding and body. The control winding hot spot temperature.
2/ Temperature control technology of liquid flow circuit: it is a technology to determine and control the liquid flow temperature of each part by comprehensively considering the relationship between the liquid velocity field and temperature field. Control the boundary layer liquid temperature and top layer liquid temperature near the hot spot of the winding.
3/ Overload temperature control technology: temperature rise control of various parts of the transformer under overload state. The temperature distribution under overload conditions is different from that underrated load operation. Attention should be paid to the temperature rise change under overload conditions in design.
4/ Iron core temperature control technology: temperature control of insulating parts in contact with the iron core.
5/ Sealed temperature control technology: the thermal expansion, deformation, strength, etc. of the fully sealed oil tank, the influence and control with the change of temperature, so as to ensure the normal operation of the transformer within its allowable temperature range.
6/ Component temperature control technology: components shall be made of insulation materials of the corresponding grade according to the temperature of their location, such as sealing gasket, etc.
7/ Short circuit temperature control technology: in case of a transformer fault short circuit, the value of short-circuit current flowing through the winding is very large, but the time is very short. It is usually calculated according to the adiabatic process. Under the condition of multiple short-circuit reclosing, the heat accumulation and heat dissipation effect shall be considered. Generally speaking, due to Nomex ® The paper has good high-temperature resistance and mechanical strength, and the change of dielectric coefficient and dielectric loss with temperature is very small. Even under the condition of multiple short-circuit reclosing, it will not cause mechanical damage and electrical failure due to temperature rise, and will not lose the service life of insulating materials.
\ CORE TECHNOLOGY \
The active part adopts a high-temperature resistant hybrid insulation system, preferably matching parts, truly the same 30 years design of the life-span.
Oil transformer all adopts the basic structural form of traditional transformer. The core is heart-type; the high-voltage winding adopts pancake-type coil; the low-voltage winding adopts wire-wound or foil-type coil according to different capacities. The biggest difference with the traditional transformer is the choice of high-temperature-resistant insulating paper. The insulation structure of 35kV and below oil-immersed power transformer belongs to the mixed insulation system, the wire turn insulation uses high temperature resistant insulating paper, and the insulation material with a lower temperature coefficient is used in the lower temperature parts.
The oil-immersed power transformers use high temperature-resistant insulating paper as insulation material and use different temperature resistant grade insulation materials for different temperature parts according to the temperature field principle, so it has good temperature resistance performance and a large margin in the design.
High-temperature resistant transformers can be safely operated in more than 40 ºC ambient temperature and do not affect their lifespan. It is safe and reliable even when operating at 20% overrated capacity. It provides a good solution to the problem of safe power supply during peak load periods.
\ TECHNICAL ADVANTAGES \
RESEARCH & DEVELOPMENT TEAM - CEEG has established a strong technology R & D team, with technology R & D platforms such as a postdoctoral workstation, Jiangsu power transformation equipment engineering technology research center, Jiangsu Graduate workstation, and Jiangsu technology center, in conjunction with the Institute of electrical engineering, Chinese Academy of Sciences, Southeast University, Nanjing University of Aeronautics and Astronautics, Jiangsu University China University of Mining and technology, and other well-known scientific research institutions and universities jointly carry out a series of technological R&D and innovation.
CLOUD PLATFORM
- It integrates the functions of electromagnetic optimization design, parametric drawing, performance analysis, structural optimization, and automatic drawing of the transformer, so as to realize the sharing of transformer design resources, search, modification, and version control of various data information.
INTELLIGENT OPERATION & MAINTENACE PLATFORM - Online power quality analysis and fault alarm can be realized by collecting key data such as transformer temperature, current, voltage, vibration, and grid harmonic, and can be installed on mobile phones.
\ USE & INSTALLATION \
SERVICE CONDITIONS -
The installation site shall not be flooded by water, the altitude shall not exceed 1000m, and the ambient temperature shall not be higher than 40ºC. The relative humidity is 100%, and the environment is 40ºC to -25ºC (-25ºC requires an on-load tap changer and temperature controller).
The installation site shall be clean, free of conductive dust and corrosive gas, and have good ventilation or artificial ventilation conditions.
During product installation, it shall be 300mm away from walls and other obstacles, and there shall be a distance of 300mm between adjacent transformers. For distribution boxes and other places with limited installation space, the above distance can be adjusted appropriately.
PACKAGING & TRANSPORTATION - The products can be partially disassembled and transported (such as on-load tap changer, temperature controller, air cooling device, enclosure, etc. can be packaged separately) or packed as one piece in packaging boxes for transportation.
During the lifting process of the package, ropes shall be hung on sleepers at the four corners at the bottom of the package. Special lifting devices should be used to lift the products after the package is opened. It can be lifted 100mm - 150mm above the ground first, and then formally lifted after there is no abnormality.
During transportation, there shall be no upward and downward slope greater than 15° on the road. In order to ensure that the vehicle can bear the load evenly, the product center of gravity shall be located on the vertical centerline of the vehicle during loading. In order to prevent displacement and rollover during transportation, the long-axis direction of the product shall be consistent with the transportation direction, and the product shall be firmly bound on the vehicle.
VISUAL INSPECTION BEFORE INSTALLATION - After opening the package, remove the protective device and check the external conditions, especially paying attention to the mechanical integrity of the coil and iron core, and the bolt fastening at the connection.
After inspection, all fasteners, coils, and iron core pressing parts must be tightened in turn without any looseness.
Use dry compressed air or a clean cloth to clean the dust and dirt on the product.
When the storage time is long and there are water droplets or condensation on the transformer surface, it shall be dried until the insulation resistance of the coil is qualified.
INSPECTION BEFORE OPERATION - Measure the DC resistance of high voltage and low voltage windings. Then check the grounding of the iron core to see whether the grounding is reliable and whether foreign matters are overlapping. Last to test the insulation resistance.
ENERGIZING - Before putting into operation, the transformer shall be put into trial operation under no-load, and the protection system shall be checked and adjusted after 3 times of impulse closing.
When the product leaves the factory, the tap positions of voltage regulation at the high-voltage side are connected according to the rated position. Voltage adjustment is required during operation. The corresponding tap connection voltage is indicated on the nameplate (when there is no excitation voltage regulation), and it must be carried out when the transformer power supply is cut off.
\ ABOUT CEEG \
3 INDUSTRIAL ZONES
4 FACTORIES
15 OVERSEAS BRANCHES
80+ GLOBAL MARKETS
THIS IS OUR DEVELOPMENT -
Headquartered in Nanjing, CEEG has always been adhering to the core values of "foresight, innovation, and responsibility" since its establishment in 1990, focusing on production and manufacturing for more than 30 years. In years of development, CEEG has Integrated independent research and development, intelligent manufacturing, and smart marketing services.
OUR PRODUCT - Our technical team has continued to explore and innovate boldly, and has successfully developed nearly a hundred products including evaporative transformers, load centers, 35kV amorphous dry transformers, nuclear power transformers, slow harmonic transformers, high-temperature transformers; there are also outstanding players in market segments: traction transformers, variable current explosion-proof transformers, multiple Pulse wave phase shifting, wind power conversion, photovoltaic conversion, three-phase three-column amorphous conversion, intermediate test conversion, data center supercomputing mobile equipment, etc. Among them, the star products of the company are the green and energy-saving "amorphous alloy dry-type transformer", the technology-leading "epoxy cast dry-type transformer", and the safe and reliable "flameproof dry-type transformer for mine use and mobile substation". The technology applied to the production has won more than 70 patent technology qualification honors.
OUR PARTNERS - Our products have been safely operating in major coal groups such as Shenhua Group, Anhui Tongling Mining Group, Pingdingshan Coal Industry Group, Jincheng Coal Industry Group, and Kaolain Group. Many well-known companies such as China Mobile, China Telecom, Inner Mongolia First Machinery, Inner Mongolia Pingzhuang Energy, and Jialing Motor also have established good partnerships with us. We also established long-term strategic cooperative relations with excellent enterprises all over the world, and our business partners include many great companies such as DuPont, Siemens, Hitachi Metals, and ABB. Our power transformers have been sold to over 80 countries and regions and got high recognition from customers overseas.
Audited Supplier 
){kind=link}