What lies behind the energy losses in transformers? Two main culprits are iron loss and copper loss. These energy losses significantly impact the transformer’s performance, reliability, and efficiency. To understand the underlying mechanisms and minimize effects, let’s delve into the details of these energy losses. 

EVR Electricals are designed to surpass traditional transformers by enhancing efficiency and performance. We achieve this by using advanced core materials and optimized core designs to reduce iron loss in the transformer. To address copper loss in a transformer, EVR features enhanced winding designs, efficient load matching, advanced cooling systems, and variable regulation capabilities. These innovations collectively ensure that EVR transformers are more efficient and effective than their traditional counterparts.

What is energy loss in a transformer?

Energy loss in a transformer occurs when electrical energy is dissipated as heat, sound, or vibrations, rather than being efficiently transferred from the primary coil to the secondary coil. This inefficiency arises from several factors, including copper losses, iron losses, flux leakage, eddy currents, hysteresis, harmonics, aging of materials, and overheating. These losses reduce the transformer’s efficiency, raise operating temperatures, decrease reliability, shorten lifespan, and lead to higher energy costs.

What are the two main types of losses in a transformer?

The two main and major energy losses in a transformer are iron loss and copper loss. Let’s know about these main energy losses.

1. Iron loss in a transformer:

Also known as Core loss, it occurs in the transformer’s core and is primarily due to hysteresis and eddy currents.

Hysteresis: Hysteresis occurs due to the repeated magnetization and demagnetization of the core material with each cycle of the alternating current (AC). This repeated process results in energy loss in the form of heat, contributing to the overall iron or core loss in a transformer.

Eddy currents: Eddy currents are loops of electric current induced within the core material by the changing magnetic field. The eddy currents circulate through the core material and produce heat due to resistance. This heat generation contributes to iron loss in the transformer.

Both hysteresis and eddy current losses are key contributors to the iron or core loss in a transformer, which significantly affects the transformer’s efficiency.

2. Copper loss in a transformer:

Copper loss in a transformer, also known as winding loss, occurs in the transformer’s windings due to the electrical resistance of the conductors. As current flows through the windings, some electrical energy is converted into heat because of the resistance in the copper or aluminum wires. This heat generation is known as copper loss and impacts the transformer’s efficiency.

What are the differences between iron loss and copper loss in a transformer?

Key differences	Iron loss in a transformer	Copper loss in a transformer
Location of loss	Occurs in the transformer’s core	Occurs in the transformer’s windings
Causes of loss	Primarily caused by two factors:. Hysteresis: Energy is lost as heat due to repeated magnetization and demagnetization of the core material. Eddy currents: Energy is lost as heat due to circulating currents induced within the core material by changing magnetic fields.	Copper loss in a transformer is the energy lost as heat, primarily caused by the resistance of the conductor material. Additional factors that can contribute to increased effective resistance include the skin effect and proximity effect.
Dependence on load	Iron loss in a transformer depends on the core material and the operating frequency, not on the load.	Copper loss in a transformer increases with the load current. As the load current increases, the resistive heating in the transformer’s windings also increases, leading to higher copper losses.
Impact on transformer efficiency	Affects transformer’s efficiency due to heating of the core material and is typically constant.	The impact on the transformer’s efficiency by copper losses is due to the load.
Heat generation	Heat is generated due to magnetic field changes in the core material.	Heat is generated due to resistive heating of the transformer’s windings.
Frequency dependence	Iron loss in a transformer is directly related to the operating frequency. This is because hysteresis and eddy current losses in the core material increase with higher frequencies.	Copper loss in a transformer is dependent on the current flowing through the windings, not on the operating frequency.
Material dependency	Iron loss in a transformer depends on the core material’s magnetic properties and design.	Copper loss in a transformer depends on the conductor material’s resistivity and cross-sectional area.
Effect of transformer design	Iron loss is influenced by core design, material, and construction.	Copper loss is influenced by winding design, conductor material, and cooling methods.

How to reduce iron loss in a transformer?

Reducing iron or core loss in a transformer requires optimizing several factors related to core material and design. Here are some effective strategies to minimize iron loss in a transformer:

Core materials: Using high-quality silicon or amorphous steel as core materials will lower hysteresis and eddy current losses, thereby improving the efficiency of the transformer.

Core design: Designing the core material to minimize flux leakage and using thin laminations to reduce eddy current losses can enhance the overall efficiency of the transformer.

Frequency optimization: Use transformers at their designed operating frequency to avoid unnecessary increases in core losses. Reducing the frequency, if feasible and practical, can lower hysteresis losses, thereby improving the transformer efficiency.

Flux density control: Reducing the core flux density can lower hysteresis and eddy current losses. This can be achieved by designing transformers to operate at lower flux densities, if practical. 

Inspection and Maintenance: Regular inspection and maintenance of transformers ensure the core and laminations are in good condition and are free from damage.

How to reduce copper loss in a transformer?

Reducing copper or winding loss in a transformer requires optimizing several factors to minimize the resistive heating in windings. Here are effective methods to reduce copper losses in a transformer:

Size of conductor: To reduce the resistance of the windings, employ thicker or high-quality conductor wire, this will enhance transformer performance. 

Material of conductors: Conductors made of materials like aluminum or high-quality copper alloys can reduce the resistance of transformer windings.

Winding design: Optimizing the number of windings and the layout will also reduce the resistance thereby achieving optimum transformer performance.

Load current: Operating the transformer based on its capacity and load requirements can help the transformer perform efficiently. Under lower load conditions, the current flow to the windings is reduced, thereby minimizing copper losses.

High-efficiency transformers: Investing in highly efficient modern transformers will minimize copper losses and lead to better performance. Modern transformers are built to reduce the copper losses and maximize the performance.

Cooling system: Efficient cooling systems can maintain the performance of the transformer at an optimum operating temperature thereby preventing excessive heating and reducing the resistance.

Harmonic distortion: Due to higher frequency currents, harmonic currents can increase copper losses in a transformer. So, designing transformers with filters or systems reduces harmonic distortion and copper losses.