Power transformers are critical components in many electronics and electrical applications because they help transfer power between circuits. They generally rely on the inductive coupling to do so. These devices convert power levels during the transfer process, increasing or decreasing with the application’s restrictions and requirements.

Power transformers are available in various designs, sizes, and ratings to suit any project need. Thus, resulting in custom power transformers which you will learn in this article by Daelim.

Daelim is an electrical company specializing in designing, engineering, and manufacturing top-tier electrical products and solutions. With a reputation of 15 years, the company has built a reputation for delivering different facets of the electrical industry. Daelim only hires the best experts to deliver the best services.

Pad-mounted Transformer

We can provide you single phase and three phase pad mounted transformer

Dry-type Transformer

Type:Cast resin; Rated Capacity: Up to 25MVA; Rated Voltage: Up to 36KV;

Pole Transformer

TypeCSP type Frequency: 50/60Hz; Rated Power: 5~167kva

Dry-type Transformer

Frequency: 50/60Hz Rated voltage:10kv, 20kv,30kv Rated Power: 400~2500kva


What are Custom Power Transformers?

A power transformer is a type of transformer used to send electricity from distribution circuits to generators. Professionals use these transformers in distribution networks to step down and intensify voltages.

The usual form of power transformers is fluid immersed. Professionals use these devices in three types according to the ranges. They are large power transformers, medium power transformers, and little power transformers.

Selection Method of Distribution Power Transformer

More information you want to know:14+FAQ ABOUT THE POWER TRANSFORMER IN SUBSTATION

How Does a Power Transformer Work?

Power transformers work on the principle of Faraday’s induction law. This law states that electricity will flow in only one direction through a loop of wire. And, when a magnet is within its field, it will create an electric current in the wire.

The structure of a power transformer is a combination of metal and sheet-covered components that create a curved shape. The transformer can either be a shell or core type and have three 1-phase or 3-phase winding wrapped around it.

What is the Difference Between 1 Phase 2 Phase and 3 Phase Power?

Single-Phase Power Design

You need to isolate three single-phase power transformers from each other. Then connect them to provide continuity of service.


Three-Phase Power Design

Meanwhile, the 3-phase transformer is a cost-effective way to provide power to your equipment, with less power loss. With its lower footprint and higher efficiency, the 3-phase transformer is a great way to power your business or home. But, it will not perform even with one dysfunctional part.

The transformer stays cool and safe by its fire-retardant fluid inside a tank mounted on the liquid tank. The conservatory allows for the oil to cover the transformer completely. More so, the charger drains to one side of the tank, allowing for voltage change and optimized voltage levels.

In addition, bushings of the tank leave parts to exactly traversing the system without damaging the outer shell. The power transformer is often operated beyond its low rating and has to stay within the 65ºC threshold. 

Manufacturers build transformers with special fans that cool the transformer’s center for operating on a point below certified temperature.

Transformer three-phase dual power supply automatic switching

Common Types of Custom Power Transformers

Below is the common type of custom power transformers widely used in the market.

Custom Inductors

Inductors are electromagnetic devices that store energy during a magnetic flux. Current flow through a coil or winding produces a magnetic flux during a core of magnetic material like steel. Additionally, professionals frequently use inductors for electrical and electronic applications.

In DC circuits, electricians use inductors to filter out unwanted noise and smooth out the current flow. Meanwhile, electricians use custom inductors AC circuits for various purposes, including noise reduction and power factor correction.

Custom inductors are suitable for both high voltage and high current applications. They are prominent in sensors, tuning circuits, energy storage, motor drives, rectifiers, power supplies, and battery chargers.

Three-Winding Transformer | Three-Phase Transformer | Daelim

Ferroresonant Transformers

Manufacturers design Ferroresonant transformers to regulate the power source with the non-linear operation. They provide voltage regulation, reduce harmonics, and limit current. In doing so, this device regulates output voltage, current limiting, and other benefits while being independent of electronic control circuits. 

Ferroresonant Transformers have a core, a primary coil, two secondary windings, and a magnetic shunt. The secondary current is limited to a safe level if an extreme overload or a short circuit occurs. Furthermore, the primary current is less than a normal full load.

Other benefits include swinging the input voltage to match the output voltage with what’s needed. They also provide ruggedness and reliability adjustable output voltages for selected models, high levels of isolation. More so, a quasi-square wave output waveform reduces filtering requirements for a C-load application.

Line Conditioners

Line conditioners provide filtered and controlled power to electrical and electronic loads, which are sensitive to power quality. Transients and poor voltage regulation can cause damage and poor performance. So it’s important to give these sensitive loads the best possible treatment with line conditioners.

Power conditioning isn’t as simple as it sounds. The term “power conditioning” can be misleading as “power” here generally refers to electricity. “Electricity” is different from the more technical electrical power. Conditioners specifically work to smooth the sinusoidal AC waveform and maintain a constant voltage over varying loads.


Three-Phase Transformers

Three-phase power transformers are ideal for electrical systems that need high-power distribution, efficiency, and high transmission capabilities.

A three-phase transformer is formed of three sets of primary and secondary windings. The first set is wound around one leg of the iron core, while the second set is on the other. Lastly, the third set is wound around an iron core assembly that’s located between them.

These primary and secondary windings are connected in either a delta (Δ) or Y configuration to make an entire unit.

Toroidal Transformers

Toroidal transformers feature a ring of a magnetic coil with a copper winding that encircles the core. Because of this unique shape, they offer extra efficiency and a variety of other advantages for industrial applications.


Closed-core inductors and transformers often used cores with a square shape within the past. Later on, the utilization of toroidal-shaped cores has increased greatly due to their superior electrical performance. The advantage of the toroidal shape is that the quantity of magnetic flux that escapes outside the core is low.

Toroidal inductors and transformers are used in various electronic circuits, including power supplies, inverters, amplifiers, and TVs.

What's The Difference Between Power Transformer And Distribution Transformer

The power transformer is commonly performed at 100% load because it is modeled to have high efficiency at load. Meanwhile, the distribution transformer has high efficiency once the load stays between 50% and 70%. Technically, distribution transformers are not desirable to operate at 100% load constantly.

Because power transformers lead to high voltages, they also need to be large and heavy. However, they are also very well insulated and can support a large number of windings.

Power transformers are typically not connected to homes directly, so they experience little load fluctuations. On the other hand, distribution types experience heavy load variations. They are designed to handle these fluctuations all day long, so iron and copper wastes take place all over the day.

Applications of Custom Power Transformers

Custom power transformers are the way to go for efficiency, reliability, and quality in industrial applications. They are a viable choice, whether you need a transformer for a compact application or a solution for power generation.

You can use them as power supplies, circuit control, portable power distribution, battery chargers, inverters, and AC/DC smoothers.

Distribution Transformer Selection of An Office Building

What Is A Custom Transformer?

Custom transformers are a way to condense the process of standard transformers into a single transformer. You can easily create your custom transformer as well as turn any existing sequence into a custom transformer.

What Are The 3 Primary Types Of Voltage Transformers?

Voltage transformers classification is into three primary types: electromagnetic, capacitor, and optical. Experts call these electromagnetic transformers because they transform by electromagnetic induction. 

However, this is a generalization of transformer types and not defined in just three types. Technically, professionals subdivide transformer types depending on their function, winding, cooling, etc.

Electric Pole Transformer | Single Phase Transformer

Which Transformer Is Used In Home?

Distribution transformers provide the final voltage transformation in the electric power distribution system. They step down the voltage used in the distribution lines to the level needed by customers’ homes.

If mounted on a utility pole, they’re called pole-mount transformers. Meanwhile, suppose distribution lines are at ground level or underground. In that case, distribution transformers are mounted on concrete pads and locked in steel cases. Thus, referred to as distribution tap pad-mount transformers.

Distribution transformers provide alternating current. They supply electricity from the public utility to buildings, a mainline to a branch line, or feeders in the same hierarchy. In their design, you must keep their iron losses at the lowest level possible.

Custom power transformers are among the most widespread electrical components because of their function. They are in high demand for various applications like electronic devising and power distribution. Thus, getting high-quality custom power transformers is necessary to ensure the best reliability.

In this regard, Daelim is a global leader in electrical products and solutions. Owning the leading transformer brand, Daelim Belefic is your partner for every electrical product or solution you may need. From custom power transformers to high-voltage transformer designs, Daelim has it all. Be sure to contact Daelim for further inquiries.

About Bin Dong

Hello, I am Bin, General manager of Daelim which is a leading transformer manufacturer. As a expert, I am glad to share my experience in transformer to you. I believe our professional team can always provide you with high quality service and we are ready to provide you with one stop solution. If you have problems when you are looking for the equipment, what you need to do is tell us.