Laminated Core is a rectangular shaped type of soft magnetic core. which has been specially designed to carry large input and output power transmissions since loss due to eddy currents is less. which has been extensively used in power transformers, Distribution transformers, and Isolation transformers.
Because the laminated is not designed to have any currents passing by. This is because of the conducting loop that experiences a changing magnetic field. Will have an amount of current looping to each core which is known as eddy current.
Laminated terms such as each layer are made up of insulated layers of steel plate that are nicely glued together and compacted into a solid core rather than a single piece of a solid block.
It can be made of different laminated silicon steel of higher grades. Material selection plays a very important role in minimizing core loss. Therefore Cold Rolled Grain Oriented Known as CRGO primarily uses core lamination due to its power efficiency and life cycle. Silicon steel materials contain silicon, which has led to increased resistivity and reduced eddy currents.
While considering the design of laminated core many factors are being considered like shelf and service life, reliability, price value, etc. Weight is always considered crucial while designing the core for the right selection of material as per design for optimized efficiency.
As per faraday laws currently induced by an alternating magnetic field with a right-hand rule for the thumb. The induced currents would always flow 90 degrees to the plane of each piece of the single lamination core.
Higher frequency electronic applications are specially made with very thin material with application suitable varnish in between sheet layers to give a thin coat of insulation and better performance.
These cores are laminated and reduced to a minimum as they obstruct the efficient power transmission of energy from primary to the secondary coil.
How Laminated Cores are better than solid iron cores?
Laminated cores are used (rather than solid cores) to prevent these eddy currents flowing through circulating currents which have been set by magnetic fields that can break down cores into sheets each coated with insulating material that does not conduct electricity and allows eddy currents to flow.
When it comes to the core material in a transformer if you use solid iron just plain solid iron or any other solid ferromagnetic substance as the core for a transformer you’re going to have problems.
Because you’re going to get circulating currents in that iron which will heat it up and cause loss and loss of efficiency for your transformer it can in the extreme case heat up the core to the point where it cracks and damages.
Which makes it impossible for these eddy currents to occur, which is what is meant by a laminated transformer core, it’s quite effective at 50 or 60 Hertz alternating current for the purpose of power transformers it begins to lose though.
With audio and radio frequencies more often than powdered iron or ferrite for high permeability powdered iron, these types of materials work better in audio and radio frequencies but not so well at alternating current power frequencies like 50 or 60 Hertz then you’re best off with a laminated core of thickness in a range of 0.20mm to 0.30mm for each sheet.
Why is the core of the transformer laminated?
The core of the transformers needs to be laminated to reduce the eddy current that has arisen from the induced voltages through the core reducing the heat loss of the whole core which is why the core of the transformers is laminated to restrict the eddy currents flowing through it.
The transformer core made from e and I lamination transformer core made from e and I lamination eddy currents are generated in a transformer core which heats the core and causes losses by altering the current. if the core is one component, its size is wide and thus small, which reduces losses due to a greater current.
The region is reduced as laminations are given thus the resistance becomes very strong and the current becomes restricted to a small value. Since the amount of the current will always be less than by using a core. Unless we had laminations, the iron core would provide the magnetic lines with a place to generate induced currents and this flow in the center would very rapidly heat up the core and waste energy.
Features of Laminated Core
1. Reducing the loss caused by eddy currents. Loss caused by eddy current lamination helps to reduce by minimizing the entire cross-section area through electrical insulation by varnish coating.
2. Light Weight. Laminated Core is gapped with a thin layer of electrical insulation material which makes a 50% reduction in material as well as weight compared to other solid cores.
3. Electric High Silicon Steel as material. Silicon plays a very big role in laminated core-based transformers. as it increases the resistivity and reduces the loss caused by eddy current loops.
4. Increase in the overall efficiency of transformers. As it has a compact design, the magnetic flux flowing through the core from primary to secondary winding does not get wasted.
At Nicore India our laminated cores are classified in two sections one lamination cut core and the second one EI lamination core is made from higher-grade materials of silicon steel imported from top steel mill companies such as JFE Steel Corporation, POSCO India Pvt.Ltd., Nippon Steel Corporation, etc.
We have completely automated machine facilities for cutting and lamination integrated imported technology from Japan and China to accurate precision work with perfect dimension and tolerance. It can be made and customized as per customer requirements.