Distribution Transformer Basics: What Every Engineer Should Know

The importance of having reliable and efficient power supply services increases more and more in our modern world. However, services face numerous complexities such as energy use, the cost of maintenance, and energy distribution, all while struggling with voltage fluctuations.

Behind the scenes, wonders, ensuring safe and effective power delivery to homes and businesses, sit the distribution transformers. In this blog post, we will discuss the importance of transformers, how they operate, their key benefits and tips for selecting one that helps meet your energy needs. Keep reading!

1) What is a Distribution Transformer?

“Every power supply system is incomplete without a distribution transformer. The device receives high-voltage electricity from power lines and converts it to a safe, lower voltage suitable for use in homes (offices, factories, etc.).”

Transformers serve as a link between electricity users and professionals operating power plants. The electricity generated by power plants is too strong for normal use, and if supplied without moderation, it would result in dire consequences, such as damaged safety gear and risk.

The distribution transformer's job is to prevent power use within a range that is too high or too low. You can find them installed on poles, mounted on concrete and even hidden underground.

Distribution transformers transform voltage with little energy loss. Some designs and materials allow even greater efficiency. While some of these transformers are small enough to be used in one house, others can supply power to a whole group of businesses or to an entire neighbourhood.

Like any other transformer, a distribution transformer is meant to run continuously. It may have to deal with energy load fluctuations as consumers draw power at different times of the day.

2) How Distribution Transformers Work

A distribution transformer is designed to change the voltage of electricity from one level to another with the aid of a magnetic field. Well, any device that does this using electromagnetic induction is capable of stepping down or increasing voltage.

The main components of the transformer include a primary coil and a secondary coil. The winding of each coil sets the transformer to the desired turns ratio. A changing alternating current flowing through the primary coil sets off a rotating magnetic field in the transformer.

Every coil produced has a specific number of loops or turns, which then dictates the voltage.

If the secondary coil contains fewer turns compared to the primary coil, then the voltage reduces. A distribution transformer performs this function; it converts high voltage to low voltage, which is safe for use.

Oil and air are most often applied internally to the transformer as a coolant. It is essential to regulate the temperature of the transformer because excessive heat would adversely affect the internal parts.

Some distribution transformers also come equipped with devices that regulate electricity when there is a load shift. This ensures that the power does not fluctuate even when the population draws a lot of electricity at once.

3) Types of Distribution Transformers

There are different distribution transformer types for every application. Understanding the types helps to pick the most suitable transformer.

i) Pole-Mounted Transformer

These are fixed at a higher altitude on electric poles and are easily visible. Moreover, they are compact in size and can be used to provide power for residential places and small industries.

ii) Pad-Mounted Transformer

These are installed on the ground in a metal enclosure. They can be located in neighbourhoods, malls, and even office buildings. All live parts are enclosed, making them much safer.

iii) Underground Transformers

These are concealed antonyms of the adapter type transformers that serve areas that do not permit the use of overhead wires, for example, busy urban regions. Their out-of-sight location helps maintain the hygiene and visual splendour of the particular region.

iv) Oil-Filled Transformers

These types are rugged and strong due to the protective and operational cooling oil. However, special precautions are needed in order to prevent oil leakage. Unbelievable, expeditious, and reliable, once set up, these models are designed for long, sustained usage.

v) Dry-Type Transformers

This type employs air-based non-combustible cooling oil as a means of preventing accidents involving spillage or combustion. When oil-based fire is out of the equation, these are placed inside hospitals, commercial complexes, and schools.

vi) Single-Phase and Three-Phase Transformers

Houses and smaller loads are hooked up to single-phase transformers, whereas Three-phase transformers are meant for superstructures, commercial establishments and industrial analysis and have larger loads.

4) Distribution Transformers vs Power Transformers: Key Differences

When it comes to working with transformers, knowing the difference between distribution transformers and power transformers is crucial. Let’s analyse the major differences:

a) Purpose

• Distribution Transformers: Allow a voltage decrease to the final level right before it’s sent to a home, factory, or office. They directly provide electricity to the end users.

• Power Transformers: These are found in transmission networks between generating stations and distribution stations, where they step up or step down voltages. They manage immense power levels of voltage.

b) Location

• Distribution Transformers:  Set up in the vicinity of homes, small industries, or shops, situated either on pads, poles, or buried.

• Power Transformers: Found at generating stations or transmission substations, which are located far from end-users.

c) Size and Capacity

• Distribution Transformers:  They have a smaller physical dimension and lower capacity, often up to 5000 kVA.

• Power Transformers: They are much larger and have extremely high capacities, often exceeding 200 MVA.

d) Operating Load

• Distribution Transformers: They run non-stop but operate on a lower load based on user demand.

• Power Transformers: They run at full load most of the time to maintain the efficiency of transmission.

e) Efficiency

• Distribution Transformers:  Optimised at 50 to 70% load for maximum efficiency, are designed to work at best performance under those circumstances.

• Power Transformers: Built for optimal performance when loaded to their full capacity or close to it.
   

f) Cooling Method
 

• Distribution Transformers:  Primarily use oil-immersed cooling or dry air cooling.

• Power Transformers: Employ more sophisticated cooling methods, such as oil with forced air or cooled oil and water.

Feature	Distribution Transformer	Power Transformer
Purpose	Final voltage reduction for users	Voltage change in transmission lines
Location	Near homes and businesses	At power stations and substations
Size and Capacity	Small, up to 5000 kVA	Very large, above 200 MVA
Operating Load	Works at variable lower loads	Works near full load
Efficiency Design	Best at 50–70% load	Best at full load
Cooling Method	Oil or air cooling	Advanced cooling systems

5) Applications of Distribution Transformers

Distribution transformers can be found in places with population because everywhere you need safe and reliable electricity. Their main job is to bring the high voltage from power lines down to a level you can use in homes, businesses, and industries.

• Residential Areas: You will find distribution transformers in neighbourhoods, where they supply power to homes. They make sure your lights, TVS, refrigerators, and other appliances work safely.

• Commercial Buildings:  Sophisticated shopping centres, bank offices, schools, and hospitals all have distribution transformers. These facilities require accurate and steady voltage for the lights, elevators, computers, and medical equipment.

• Industrial Plants: Everything like factories and manufacturing units make use of heavy machines and tools and need a lot of electricity. Distribution transformers are essential in providing facilities with the appropriate voltage.

• Agriculture: Farms require electricity for water pumps, irrigation systems, and other farm machinery, and use distribution transformers for everything. They ensure reliable electricity even in remote areas, delivering the power needed for farming.

• Renewable Energy Systems: Everything like wind and solar farms makes use of distribution transformers. They step up or step down voltages to connect renewable energy to the main power grid or supply the local areas.

• Public infrastructure: Everything like railway systems, street lights, and water treatment plants uses these types of transformers. They help power essential public services.

No matter the day or the time, the distribution transformers are constantly at work in the background, ensuring that individuals have access to power that is reliable, stable, and safe.

6) Benefits of Distribution Transformers

With everything in mind, distribution transformers can be seen as a critical element for daily energy services. Let’s take a closer look at what they enable us to do.

+ Dependable Electricity Supply: The distribution transformers give you a dependable supply of electricity. They step down the voltages that can be transmitted through the power lines so that they can be used safely using electrical appliances.

+ Enhanced Protection: Using heavy machinery or electrical appliances comes with its fair share of danger. Stepping down the voltage increases safety for individuals and industries, protects appliances from damage as well and serves to prevent electrical fires.

+ Reduction in Power Consumption: Distribution transformers these days are made with the intention of saving energy. They try their best to reduce energy wastage when distributing electricity. It eases the burden on the transformer and saves the user money.

+ Prolonged Life Span: Transformers can live a long time when maintained correctly, and are very useful for saving power. Due to their sophisticated construction and materials, service is improved in the long run.

+ Flexibility in configuration and user maintenance: The maintenance provided with distribution transformers is quick and easy. They can be placed on poles, pads, or underground.

+ Adapt to the growing requirements: As the consumption of electric power goes up, the need for transformers also rises. To meet the increased usage, the devices can be altered easily without a lot of effort.

+ Cost-Effective: Pairing lower distribution transformers with large power ones makes them more affordable. Distribution transformers offer optimal performance at a lower price, making them ideal for residential, commercial, and even some rural areas.

In sum, the distribution transformer is the unsung hero of enabling modern power technology as it is efficiently and safely brought to where it is required the most.

7) Maintenance and Troubleshooting

Distribution transformers need servicing regularly as they are likely to experience issues of unexpected failures. Unscheduled downtimes will ensure timely preventative maintenance and monitored checks on them.

• Routine Inspections: Routine inspection is very important to get good results from distribution transformers. Well, stripping away observable rust alongside their noisy counterpart adds on-board silence. Removing debris ensures that the transformer itself is in its tidy state.

• Oil Level and Quality Check: The oil-filled transformer needs its insulation oil to be checked frequently. Oil and insulation levels both cool and insulate the subsystem, ensuring its steady functioning. Contaminated oil leads to cooling and damage to internal components. It is crucial to monitor oil and maintenance.

• Oil and Air Cooling Maintenance: If the transformer is to work properly, ensure that the cooling system (oil or air) is functioning adequately. The cooling system should be checked for damage, vents should be cleaned, and fans checked for any signs of malfunctioning.

• Electrical Connections: Ensure that all the connections are checked for any electrical issues and that the contacts are not loose or rusted. Heats that are loose or rusted can cause an electrical problem, leading to the transformer not being efficient.

• Monitoring Temperature and Load: Use monitors to keep checking on temperature while the load is flowing. If the transformer is using up a lot of power while undertaking its designated work or load, then there is are high chance it might fail. With the aid of load meters and temperature gauges, you can avoid this issue.

• Troubleshooting Common Issues

Overheating transformers are usually a result of poor ventilation paired with excessive load or overload. If the transformer starts making sounds, that could mean there are serious matters occurring inside. It could be an electrical short circuit or mechanical failure. So, repairs under these situations should only be undertaken by an expert and trained worker.

8) Delixi Distribution Transformers

Delixi Electric has a collection of distribution transformers which are efficient and safe for different types of power needs. Their transformers are tailored to both residential and industrial applications, ensuring that electricity is supplied reliably.

a) S11 Series Oil-Immersed Transformers

These transformers are among those with the highest known efficiency and the least amount of loss. The imported high-conducting silicon steel sheets are further enhanced by vacuum drying and oil filling to achieve the lowest internal moisture possible. This design takes care of maintenance costs while service life can be extended.

b) SBH15 Amorphous Alloy Transformers

With advanced technology, these transformers make use of amorphous alloy cores which resulting in them having 75% lower no-load losses enduring them compared to traditional models. Their energy saving is dramatic, making them a smart choice after extended periods and costs.

c) SCB10 Epoxy Resin Dry-Type Transformers

This type of dry transformer is encapsulated with epoxy resin, offering a long life and high reliability. Maintenance and fire safety make them usable in areas that prioritise those aspects.

Delixi's distribution transformers are built with safety and performance in mind, complying with international standards. These devices can be used in residential, commercial and industrial settings without limitations. With great emphasis on power distribution, Delixi ensures modern energy efficiency and durable needs are met.

9) Safety Considerations in Handling Distribution Transformers

There are several precautions that need to be taken in the handling of distribution transformers to avoid accidents and guarantee safety. The following are some safety tips:

! Adequate Instruction: Instruction in the operation of transformers should only be given to qualified people. This includes familiarising them with electrical safety regulations, procedures, and standards relevant to the transformer.

! Protective Clothing: For electric shock safety, the individual must put on protective clothing (PPE) such as gloves, safety boots, helmets, and insulators.

! Check for Damage: Before maintenance or installation, make sure that no visible damage has been done to the transformer. Check oil-filled transformers for any oil leakage, and also the cooling system.

! Do Not Overload: Never exceed the rated capacity of the transformer. Doing so will cause overheating, which can lead to fires and other failures.

! Proper Earthing: Before working on a transformer, proper earthing must be guaranteed. Failure to provide this will incur risks of electric shock and fire.

! Ventilation: Make certain that the transformer is installed in a ventilated area, especially outdoors, so as to avoid overheating.

Practising the various tips will ensure that the person is able to handle distribution transformers without risk and that the transformers remain intact for a long time.

10) Conclusion

As we have seen, different industrial and commercial sectors require the use of distribution transformers, which are critical in reliable and safe power delivery systems. High voltage is efficiently brought down for use in homes, businesses, and industries. With their performance and life in mind, it is good practice to follow maintenance procedures and safety measures.

Delixi Distribution Transformers provide economical solutions that are intended for heavy-duty use. It is possible to guarantee an effective and reliable power supply by choosing the right transformer and observing the required safety precautions. You can contact us with a single click here.