Transformers use silicon steel sheets for their cores for a variety of reasons. These sheets, which are also known as grain-oriented silicon steel, have very desirable properties that make them well suited for use in transformers.
Silicon steel is an alloy that contains up to three percent silicon, as well as up to two percent manganese. This specific combination of elements makes the steel more resistant to eddy current losses and flux leakage. This in turn can make the transformer more efficient and require less energy to operate. It also helps with the transformers ability to resist heat buildup, which keeps it operating longer and better in efficient manner.
Silicon steel also has magnetic properties that are advantageous. It has a higher saturation flux density than other types of steel, and when the magnetic flux is concentrated, it generates more in its output. This makes the transformers ability to regulate voltage higher, providing better voltage regulation and improved performance. Silicon steel also has a better permeability than other types of steel. This allows the transformer to be more responsive to the changes in AC input voltage, which can help reduce harmonics and improve system stability.
One of the most important advantages of silicon steel is its very low hysteresis loss, which is the energy that is lost due to the magnetizing and demagnetizing of the core. This type of steel has very low hysteresis losses, which can be fifty percent lower than those of other types of steel. This low hysteresis loss makes the transformer more efficient and helps produce higher output currents.
Silicon steel is also very mechanically strong, which helps to make it well-suited for use in transformers. It has a tensile strength of over 6,000 pounds per square inch, making it very tough and resistant to deformation and other damage. Additionally, its low thermal contraction rate makes it especially well-suited for use in the cores of transformers. This low thermal contraction rate minimizes the warping that can occur during heat cycles.
The combination of these properties – higher saturation flux density, better permeability, low hysteresis loss, higher strength, and low thermal contraction rate – make it an ideal material for the cores of transformers. This makes silicon steel an ideal choice for both cost and quality reasons, and it is the material that is most commonly used in transformer cores.
