Both power and distribution transformers are essential components of the electrical system. They both reduce the voltage of current passing through them to a more usable level, but they have distinct differences.
Power transformers have a higher voltage rating between two windings and are used to transfer power from one electrical system to another. They typically have a rating of 66 kV or above and are generally located in substations.
Distribution transformers have lower voltage ratings than power transformers and are used to step down the voltage of current from a larger system. This type of transformer has a rating between 2 – 33 kV and is usually found in residential or commercial buildings.
Distribution Transformer Vs. Power Transformer
What Is A Distribution Transformer?
- It is a device that helps reduce the voltage from a larger system to a more usable level
- It has low voltage rating, generally between 2 – 33 kV
- It can be found in residential and commercial buildings
What Is A Power Transformer?
- It is essential for transferring power from one electrical system to another
- It has high voltage rating, usually 66 kV or above
- It is located in substations
Types
Types of Distribution Transformer
1.Single Phase:
- Used for residential and commercial applications
- Has one winding on each side
2.Three Phase:
- Used for industrial/utility applications
- Has three windings on each side
3.Pad-Mounted:
- Used for providing power to public places
- Mounted on a concrete pad
4.Pole Mounted:
- Used for providing power to rural areas
- Mounted on a metal pole
Types Of Power Transformer
1.Large Power Transformer:
- Used in electrical power systems
- Has high voltage rating, usually 66 kV or more
2.Small Power Transformer:
- Used in power generation, transmission and distribution systems
- Has a lower voltage rating than the large one
3.Medium Power Transformer:
- Used in both power systems and distribution networks
- Has a voltage rating between that of the small and large power transformers
Applications:
Power Transformer:
- Power transmission from generators to substations.
- Long-distance power transmission at high voltages.
Distribution Transformer:
- Low-voltage distribution from substations to customers.
- Power distribution from main lines to smaller networks.
Pros And Cons:
Power Transformer pros:
- Higher power ratings
- Longer operating periods
- High voltage power transmission capabilities
Power Transformer cons:
- Larger size and weight
- Lower tolerance for load fluctuations
- Requires regular maintenance
Distribution Transformer pros:
- Smaller size and weight
- Better load fluctuation tolerance
- Low voltage operation
Distribution Transformer cons:
- Lower power ratings
- Shorter operating periods
- Requires regular inspection for wear and damage.
Difference Between Power Transformer And Distribution Transformer
| Properties | Power Transformer | Distribution Transformer: |
| Transformer Size: | Power transformers are large, ranging from 250KVA to over 500MVA. | Distribution transformers are much smaller, typically ranging from 50KVA to 5MVA. |
| Design and Purpose: | Power transformers are designed for high-voltage (HV) power transmission and distribution. These transformers are used to step up or step down voltages to provide power at varying distances from the generator. | Distribution transformers are designed for low-voltage (LV) power distribution, usually at the edge of a network before it gets to individual users. These transformers take power from the main line, reduce the voltage and distribute it to customers. |
| Efficiency: | Power transformers are typically more efficient than distribution transformers due to their size and design. | Distribution transformers typically have lower efficiency because of their smaller size and complexity. |
| Insulation: | higher insulation requirements due to their high voltage operation. | lower insulation requirements than power transformers, as they operate at lower voltages. |
| Cost: | expensive | less expensive |
| Iron Losses and Copper Losses: | higher iron losses but lower copper loses | lower iron losses but higher copper losses |
| Maximum Efficiency: | can achieve maximum efficiency | unable to achieve maximum efficiency |
| Function: | Power transformers are used to step down or step up voltages in order to provide power at varying distances from the generator. | Distribution transformers are used to reduce voltages and distribute it to end-users. |
| Power rating: | higher power ratings and can handle more current than distribution transformers. | lower power ratings and are not able to handle as much current as power transformers. |
| Voltage rating: | designed for high-voltage (HV) power transmission and can handle voltages up to 500kV. | designed for low-voltage (LV) power distribution and can handle voltages up to 33kV. |
| Number of primary and secondary windings: | one primary winding and one or more secondary windings. | two primary windings and one or more secondary windings. |
| Operating period: | operate continuously for long periods of time, providing reliable power transmission over long distances. | shorter operating periods |
| Load fluctuations: | lower tolerance for load fluctuations as they operate at higher voltages and are unable to adjust quickly to changing loads. | Better load fluctuation tolerance and ability to adjust quickly to changing loads. |
| Operating conditions: | Operate in dry, clean environments and require adequate insulation. | Operate in a variety of conditions as they are designed to withstand fluctuations in load and voltage. |
| Maintenance requirements: | Require regular maintenance to ensure their components remain in good working order. | require less maintenance |
FAQs
What Is The Difference Between Power Transformer And Voltage Transformer?
- Power transformer is designed for high voltage (HV) power transmission, while distribution transformer is designed for low voltage (LV) power distribution.
- Power transformers usually have one primary winding and one or more secondary windings, while distribution transformers typically have two primary windings and one or more secondary windings.
What Are The 3 Types Of Transformers?
- Power transformers
- Distribution transformers
- Autotransformers (also known as buck-boost transformers)
Why It Is Called Power Transformer?
Power transformers are designed for high power transmission over long distances and can operate continuously even under light loads, which is why they are referred to as “power” transformers.
Why KVA Rating Is Used In Transformer?
KVA rating is used as a measure of the maximum power that a transformer can handle. The higher the kVA rating, the greater the amount of power it can transfer. KVA ratings are typically used to compare different types and sizes of transformers.
Conclusion
Power transformers are designed for high-voltage power transmission and are typically larger and heavier than distribution transformers. They require regular maintenance and have lower tolerance for load fluctuations. Distribution transformers are designed for low voltage power distribution, have better load fluctuation tolerance, and require less maintenance. KVA rating is used to measure the maximum power that a transformer can handle. Both types of transformers have their own advantages and disadvantages and should be chosen based on the particular application.
It is important to note that both power transformers and distribution transformers play an essential role in electricity transmission and distribution, ensuring reliable supply of energy for domestic, commercial, and industrial purposes.
