Maintenance Of Distribution Transformer

 Maintenance Of Distribution Transformer

Check the temperature of the transformer: See whether the upper oil temperature of the transformer is normal or near or over the maximum allowable limit from the thermometer. When there is a significant anomaly between the temperature that glass thermometer indicates and that the pressure thermometer indicates, it is necessary to find out whether the meter is not accurate or the oil temperature is abnormal.

 

The check of the oil level: Check whether the temperature of transformer oil storage cabinet is normal and if there is false oil level and oil leakage phenomenon; whether oil level of high voltage bushing and the color of oil is normal and whether bushing has oil leak phenomenon.It is necessary to find out the cause when the oil level indication is not normal. And it is also necessary to pay attention to the path of the oil level indicator and we must ensure that there is no accumulation at the entrance.

 

Check the sound: Check whether there is abnormal comparison between the electromagnetic sound of the transformer and the previous sound. Staff are usually accustomed to the normal noise of the transformer, and if there is an abnormal sound, they will find it easily.

 

Check the insulation on the top cover of the transformer: See whether the supporting insulator surface of the outline casing and extraction electric conduction is clean; whether there is a rupture or electric discharge or other defects.

 

Check the bolt joint that leads the conductor whether has superheating phenomeno: Check the change of the visual temperature wax sheet and the discoloring paint or directly measure it by the infrared thermometer flexibly. When there is a cable terminal box, the oil leakage of the cable head should also be checked.

Yuebian Electric Co.,Ltd, a large-sized electrical transformer manufacturers, we provide power transformer, compact substation, package substation, step down transformer, dry transformer, oil transformer, oil immersed transformer, dry type transformer and etc. Want to know more? Please contact us.

 

How to Choose A Transformer: Dry Type Transformer and Oil Immersed Power Transformer

 How to Choose A Transformer: Dry Type Transformer and Oil Immersed Power Transformer 

 

Transformers are a common and useful device that receives high voltage directly from a power station and converts it to a lower voltage. This enables safe and efficient use of machines and equipment that can handle low voltages in spaces such as offices, transportation hubs, schools and factories to save energy.

 

Through this process, the transformer generates a large amount of heat that must be dissipated to maintain safe operation. There are two types of transformers currently used in the industry: dry type transformers and oil immersed power transformers. Dry air is used as the cooling medium, and liquid cooling is used as the oil. Although both types have the same end result, it's worth noting that there are many differences between them that will affect the type you choose.

 

Dry Type Transformer Maintenance: Oil immersed power transformers require more maintenance procedures and must be executed more frequently than dry. Oil needs to be sampled to test for contamination, while dry type transformers are highly resistant to chemical contaminants.

 

Cost (initial and running): Dry type transformer has significantly higher operating losses compared to oil immersion. Oil filled transformers have a higher standard energy efficiency and therefore have a higher service life than dry type transformers.

 

Noise: Oil immersed power transformers operate at lower sound levels, so noise pollution is lower than dry.

 

Recyclability: The life cycle of dry recycling is limited, while the core/coil recovery of petroleum plants is easier. Oil immersed power transformer has superior service life and maintainability, produces less waste, and requires less replacement and labor.

 

Efficiency: Dry type transformers are larger units with limited voltage and size. If they experience overload, they are more likely to overheat. As a result, they have higher electrical losses and it is more expensive to maintain dry power over time. Oil-cooled units are smaller and more efficient. They have less demand and a smaller environmental footprint.

 

Voltage Capability: Dry type transformers are designed to handle small to medium MVA and rated voltages, making them ideal for small applications. Oil immersed power transformers can withstand heavier loads, so applications that require higher voltages will require oil units.

 

Location: The location of the transformer will be the biggest determinant of which type you need. Dry design is used near buildings and buildings simply because they are safer for the environment. Dry type transformers are less flammable and less risky to fire, making them ideal for shopping malls, hospitals, residential areas and other commercial areas. Oil immersed power transformers are used for outdoor installations because there may be oil spills, which pose a fire hazard, but these devices are more environmentally friendly.

 

Taking into account these variables, petroleum plants appear to be a better choice, with higher energy efficiency, recyclability, low noise pollution, lower operating costs and a small environmental footprint. However, petroleum equipment cannot be used at all under any circumstances. Dry type transformers are the best and multiple must-have option for commercial and indoor operations because they are safer units that operate around people and areas where fire hazards may exist.

 

YueBian has oil immersed power transformer for sale and dry-type power transformer for sale, which are available upon request.

Yuebian Electric Co.,Ltd, a large-sized dry type transformer company, we provide power transformer, distribution transformer, step down transformer, dry transformer, oil transformer, oil immersed transformer, dry transformer, dry type transformer and etc. Want to know more? Please contact us.

 

Electrical Transformer Winding

 Electrical Transformer Winding

There must be some insulative gap and heat dissipation channel (oil passage) between high voltage winding and low voltage winding, and between low voltage winding and core column, and insulated with cardboard tube. The size of the insulation distance depends on the voltage level of the winding and the clearance required for the heat dissipation channel. When the low voltage winding is placed near the core column, because the insulation distance between it and the core column is relatively small, the size of the winding can be reduced, and the size of the whole transformer will also shrink at the same time.

 

The transformer winding is set on the core column of the transformer, the low voltage winding is in the inner layer, and the high voltage winding is set in the outer layer of the low voltage winding to facilitate the insulation. It is easy to be insulated from iron core. The iron core is a grounding electrode, and the iron core stack is capacitive grounding.

 

The arrangement of the three windings in the inner and outer layers of the core column should consider both the convenience of the insulative treatment and the direction of the power transferring. Considering from insulation, the high-voltage winding should not be placed on the core and should be placed in the outer layer.

 

When the three winding transformer is used in the boost stage of the generator, the direction of the power transferring is transferred from the low voltage winding to the middle and high voltage side. The low voltage winding is placed in the middle, and the middle voltage winding is arranged in the inner layer. When used for pressure reduction, the direction of power transmission is transferred from the middle side and the low side of the high voltage side. The middle voltage winding is placed in the middle, and the low voltage winding is arranged in the inner layer.

Yuebian Electric Co.,Ltd, a large-sized distribution transformer manufacturers, we provide power transformer, distribution transformer, step down transformer, dry transformer, oil transformer, oil immersed transformer, dry type transformer and etc. Want to know more? Please contact us.

 

Electrical Transformer Maintenance

 Electrical Transformer Maintenance

It is a fundamental requirement for transformer professionals to understand its working principles and the internal structure of the transformer itself. Before the repair work, the staff must be prepared to analyze the possible problems and prepare the various materials and tools to be used in the maintenance. At the same time, contact with the welder, the engineer, the chemical oil treatment personnel and so on the staff that may help, and let them coordinate work. A power outage should be conducted prior to the maintenance of the transformer, and the transformer shall be in a state of stop working, and adjust all the things accordingly as needed. At the same time, the staff should pay attention to their own clothes and other things, don't dress a lot of jewelry or other things on the clothes, and to ensure the safety, don't bring any other small devices, and avoid mistakes or things that are forgetted that affected the transformer maintenance and repair work.

When everything is ready, with the knowledge of the transformer, skilled technical, proficient skills, and light packing, the staff can start to repair work. Of course, always keep in mind the belief of "safety first" in the maintenance process.

Yuebian Electric Co.,Ltd, a large-sized oil filled transformer manufacturers, we provide power transformer, distribution transformer, step down transformer, dry transformer, oil transformer, oil immersed transformer, dry type transformer and etc. Want to know more? Please contact us.

 

Efficiency Of Transformer

 The efficiency of the transformer: At the rated power,the ratio of the output power and input power of the transformer  is called the efficiency of the transformer,that is η= x100%. The η in the formula is the efficiency of the transformer; P1 is the input power and the P2 is the output power.When the output power of the transformer（P2） equals the input power（P1）, the efficiency of the transformer is equal to 100% and the transformer will not produce any loss. But in fact this transformer does not exist. When the transformer transmits electrical energy, it always produces loss and this loss mainly includes copper loss and iron loss. Copper loss refers to the loss caused by the resistance of the transformer coil. When the current passes through the coil, it will cause the resistance heating. And part of the electrical energy is changed into heat energy and this part of energy is lost. Because the coil is usually twisted by the insulated copper wire, it is called the copper loss. The iron loss of the transformer consists of two aspects. One is the hysteresis loss. When the alternating current passes through the transformer, the direction and size of the magnetic line of the silicon steel sheet will change along with the transformer, so that the internal molecules of the silicon steel sheet will rub each other and give off heat energy, which will consume part of the electric energy. This is the hysteresis loss. The other is eddy current loss. When the transformer is working, a magnetic line of force will pass through the core, and an induction current will be generated on a plane perpendicular to the magnetic line of force. Because the current itself forms a closed loop and forms a circulation and presents the shape of the whirlpool, it is called a vortex. The existence of the eddy causes the core heating and consume energy and this loss called the eddy current loss. The efficiency of the transformer is closely related to the power level of the transformer. In general, the power is greater, the loss and output power are smaller,and the efficiency is higher. On the other hand, the power is smaller, the efficiency is lower.

Yuebian Electric Co.,Ltd, a large-sized power distribution transformer manufacturers, we provide power transformer, distribution transformer, step down transformer, dry transformer, oil transformer, oil immersed transformer, dry type transformer and etc. Want to know more? Please contact us.

 

Dry Type Transformer Maintenance

 Dry Type Transformer Maintenance Service

Inspect whether the installation of transformer is complete, crooked, and whether there is any local deformation or vibration.

 

Inspect whether the transformer shell is complete ans the tightness of connections. Make sure the cases are not damaged.

 

Inspect whether the surroundings of the transformer are clean and water-free.

 

Check the ventilation equipment in the distribution room or cabinet.

 

Make sure that there is no overheating phenomenon in every part of the transformer.

 

Check whether the wire of the transformer is firm, the position is normal, and the insulation distance around the lead is changed.

 

Make sure that the connection bolts in the transformer is tight, and the transformer has no abnormal noise.

 

The electrical connection part of the casing and the wiring board shall be tight and free of overheating. Check whether there is any damages to the transformer, and remove the dirt and dust from the rings.

 

Inspect he technical data and files of the last maintenance.

 

Understand the operation condition of the transformer.

 

Comprehensively check the integrity of the transformer.

 

Check the phase separation plate and the surrounding screen to make sure there is no damages, discoloration, deformation and discharge marks. Any problem should be dealt with once it was found.

 

Check whether the coil surface is clean or not as well as the conditions of the insulators. Check whether the parts of the transformer are displaced and loose, whether there is dirt and other material clogging the cooling air duct--use soft brush for cleaning if necessary. Check whether the iron core is smooth, whether there is short circuit or discoloration and dislocation situations of the chips. The dirt accumulated at the bottom of the top and bottom yoke of the iron yoke should be cleaned. If the laminated sheet is warped or irregular, use a wooden hammer or a brass hammer to make it smooth.

 

Check the firmness and insulation performance of the core, top and bottom clamp, square iron and coil pressure plate.

Yuebian Electric Co.,Ltd, a large-sized power transformer suppliers, we provide power transformer, distribution transformer, step down transformer, dry transformer, oil transformer, oil immersed transformer, dry type transformer and etc. Want to know more? Please contact us.

 

Double Wound Transformer Applications

 What is double wound transformer?

Double wound transformer is a common transformer product with main functions include voltage change, impedance transformation, isolation and voltage stabilization. The manufacturing process is different according to different applied occasions (or different purposes). Three wound transformer has three wounds of each phase. When one wound connects to the AC power, the other two wounds can induce different electric potential. The transformer is used for load which requires two different levels of voltage. Usually in power plants and substations, there are three different levels of voltage, so three wound transformer is used widely in the power system.

 

High, middle and low voltage wounds of each phase are set in the same core column. In order to make the insulation reasonable, usually the high voltage wound is put in the outer layer, with middle and low voltage wounds placed in the inner layer. Based on the high magnetic conductivity of iron materials, most of the flux is confined in the core. Therefore, the two sets of coils can get a high degree of magnetic coupling. Because of the function of voltage boost and buck, the transformer has become one of the most important appendages of modern electric power system. The increasing electricity transmission voltage makes the long-distance transmission more economical. As for step-down transformer, it makes the usage of electricity more diversified. It can be said that if there is no transformers, modern industry is unable to reach such a great level at this time.

 

Yuebian Electric Co.,Ltd, a large-sized electrical power transformer manufacturers, we provide distribution transformer, step down transformer, dry transformer, oil transformer, oil immersed transformer, dry type transformer and etc. Want to know double wound transformer operation or double wound transformer definition? Please contact us.

 

Cooling Method of Three-phase Dry Type Power Transformer

The cooling mode of dry type power transformer is divided into natural air cooling and forced air cooling. In the case of natural air cooling, the transformer can be operated continuously for a long time and the rated capacity under normal use conditions. When forced air cooling, under normal conditions of use, the output capacity of the transformer can be increased by 50%, which is suitable for intermittent overload operation or emergency accident overload operation. Since the load loss and the impedance voltage increase greatly during overload, it is in a non-economic operation state, so it should not be subjected to long-term continuous overload operation.

 

For natural air-cooled and forced air cooled transformer dry type, it is necessary to ensure that the transformer room has good ventilation capacity. When the transformer is installed in the basement or in a poorly ventilated environment, a cooling and ventilation device must be added. The fan air cooling system has low noise, uniform cooling and good effect. It is small in size and takes up little space and does not exceed the outline size of the transformer body.

 

The above is the cooling method of three phase dry type transformer (natural air cooling and forced air cooling). For more information, please pay attention to the official website of YueBian.

Yuebian Electric Co.,Ltd, a large-sized dry transformer manufacturer, we provide power transformer, distribution transformer, step down transformer, dry transformer, oil transformer, oil immersed transformer, dry type transformer and etc. Want to know more? Please contact us.