When we think about transformers, electric motors, or generators, it’s easy to focus on the external components and forget about the critical internal parts that make them work efficiently. One such internal component that plays a pivotal role in these electrical machines is the stator core. We offer custom motor rotor and stator core lamination services.
You might have heard the term “stator core laminated,” but what does it mean, and why is it essential? In this article, we’ll delve deep into the world of stator laminations, exploring why they are laminated, their benefits, and their significance in various applications.
What Is The Stator Core?
Stator lamination and rotor lamination are two key components of an electric motor. Stator core is made up of thousands to hundreds of thousands of individual steel laminations. The process of manufacturing a stator core involves continuously placing laminations side-by-side.
The goal is to form a complete circular or ringed layer with the laminations. The process involves laying out each layer until the required length or number of layers is achieved.
Production completes with the aligning and fastening of all segments or layers. Fastening involves the use of finger plates, key bars, compression rings, building bolts, and other equipment to apply compressive loads. Within the stator core are some slots or cavities to hold the coil windings, which carry electrical current.
The Role of the Stator Core
The stator core serves as the backbone of electrical machines, and its primary function is twofold:
Support for Windings
Within the stator core, there place slots or cavities where the coil windings. These windings carry electrical current and create a magnetic field when energized. The stator core provides a stable and secure platform for these windings.
Magnetic Circuit
The stator core acts as a magnetic circuit that directs and amplifies the magnetic field generated by the windings. This magnetic field interacts with the rotor (in motors and generators) or the secondary winding (in transformers) to enable the conversion of electrical energy into mechanical energy or vice versa.
What is the Lamination?
Now that we have a basic understanding of the stator core’s role let’s explore why laminating it is necessary.
Lamination refers to the process of creating the stator core by stacking and bonding thin steel sheets or laminated sheets. These solid metal laminations typically make for materials like silicon steel (electrical steel) or nickel and cobalt alloys.
Advantages Of Laminated Stator Cores
Minimizing Eddy Currents
The stator core comprises an electromagnetic field that produces a voltage, known as circulating current or eddy current.
In most cases, this type of current will result in decreased performance and power loss – caused by several factors like the density of magnetic flux and frequency of electromotive force (EMF).
Insulating the core with stator laminations reduces eddy currents. Layers of plates are placed on top of one another right in the middle to prevent eddy current flow.
As a result, the reduced eddy current will mean that the stator core is able to keep its constant power and operate efficiently.
Reducing Hysteresis Loss
The stator core’s electromagnetic field also causes a degree of magnetization known as hysteresis. The process of magnetization and demagnetization creates a loop – the bigger it is, the higher the accumulated energy consumed to magnetize and demagnetize the core.
As the core generates heat from eddy current production, hysteresis loss occurs, costing large amounts of energy and power loss. Laminations minimize hysteresis loss to increase efficiency.
Here is where lamination plates come in to prevent such an incident with their narrow hysteresis loops which do the job of magnetize and demagnetize the stator core – by using less energy. Which also translates to more efficient equipment.
Improved Efficiency
Laminated stator cores result in higher machine efficiency. The reduction in eddy current losses means that a larger portion of the electrical energy convert into useful mechanical work or maintained as electrical output. Stator laminations offer significant benefits to help optimize engine performance.
Enhanced Performance
Laminated cores offer improved performance in terms of stability and precision. The laminations ensure uniformity in the core material properties and dimensions, leading to more predictable and reliable machine behavior.
Cooling the Stator Core
Solid metal pieces in stator cores may cause the stator core to overheat, increasing the risk of melting. Laminations reduce the amount of heat the core produces, keeping it cool enough to avoid melting.
Noise Reduction
Laminations also help in reducing noise, which is especially important in applications where quiet operation is essential, such as household appliances and electric vehicles.
Materials used in Lamination
At Motorneo, We commonly use electrical steel, nickel alloys, and cobalt alloys to manufacture electrical machine stators and rotor iron cores. Here is our detailed introduction to the three materials:
laminated Steel
Thin-gauge electrical steel is ideally suitable for applications with energy efficiency and high-performance requirements. This material offers excellent magnetic properties.
We commonly use electrical steel laminations ranging from 0.1 to 1 millimeter (mm). In addition, we use grades of electrical steel like M15, M19, M22, M27, M36, M45, etc.
Nickel Alloys
In certain high-performance or specialized applications, nickel alloys may be used for motor laminations. These alloys provide exceptional magnetic properties and corrosion resistance, but they are generally more expensive than silicon steel.
Cobalt Alloys
Cobalt alloys have high tensile strength, excellent resistance to corrosion, heat, and wear and tear, and are a sought-after material for lamination. It is a fantastic choice for high-performance applications that require high flux densities and no saturation.
Capability for Lamination Process
Material Selection
The first step involves choosing high-quality raw lamination material based on the specific requirements of the customer.
Lamination Prorotypes
We produce these precise lamination prototypes using computer-controlled laser cutting machines or Wire-EDM. We can handle the most demanding motor lamination production needs within a turnaround time of 5-15 days
Tool Design And Manufacture
We will design the corresponding stamping die according to the size, shape, and characteristics of the lamination. We use Wire-EDM and grinder technologies to fabricate mold. After all, the mold is crucial to the quality and burr control of the lamination.
Cutting and Stamping
The chosen silicon steel material is then cut into thin laminations or sheets, which our automatic feeders feed silicon steel strips into our stamping machine.
The high-speed punching machine and large press machine punch and drill electrical steel strips to create the desired laminated shape. The stamping process includes creating slots for windings and ensuring precise dimensions.
Stacking and Bonding
The laminations are stacked together to form the complete stator core. Bonding agents, adhesives, or mechanical methods are used to hold the laminations firmly in place.
Winding
The stator winding consists of wire coils wound around the stator teeth. Our technician wraps the wire around specialized forms, creating coils with precise dimensions and turns. Coils inserted in the stator core designated slots and interconnected according to the winding configuration
Insulation
To prevent short circuits between laminations and windings, insulating layers or coatings are applied as a protective measure.
Quality Control
We have ISO9001:2008 international quality certification. These certifications reflect our strict quality control. Quality control measures include:
Dimensional Accuracy
We use CMM inspection and projector detector ensuring that the electric motor laminations meet the specified dimensions and tolerances.
Visual Inspection
Checking for any defects, such as cracks or irregularities in the laminations.
Magnetic Properties
Our advanced machine can test the magnetic properties to confirm they meet the required standards.
Bonding Integrity
We run tension tests to verify that the laminations are securely bonded and properly insulated.
How To Choose Lamination Thickness
We carefully choose the lamination thickness based on the specific requirements of the motor, generator, or transformer. For high-efficiency applications, we prefer to use thinner laminations. On the other hand, in applications where robustness and durability are paramount, we choose thicker laminations.
Stator Core Lamination in Different Applications
Electric Motors
AC Motors: In alternating current (AC) motors, the stator core plays a central role in creating the rotating magnetic field required for motor operation.
DC Motors: Direct current (DC) motors also benefit from laminated stator cores, which enhance their performance and efficiency.
Synchronous Motors: Synchronous motors rely on precise synchronization between the stator’s magnetic field and the rotor’s rotation
Generators
In generators, whether they are used for wind/fire power generation or as alternators in electric vehicles, the stator core is responsible for generating electrical output.
Transformers
Transformers are essential components in power distribution systems. Laminated stator cores in transformers help regulate voltage levels and minimize energy losses during electrical energy transfer.
Looking to the high-performance electric motor iron core
Looking to optimize the performance of your electrical machines and get the best stator laminations? Motorneo, your trusted professional motor lamination manufacturer in China, is here to meet your needs.
We specialize in custom stator cores that will have a thickness of around 0.1 – 1 mm, with a length of 20 – 1250 mm which a wide range of applications, including industrial motors, automotive motors, elevator traction motors, diesel generators, wind and fire power generators, rail motors, transformers, and more.
With our expertise, we offer tailored solutions in terms of size, thickness, and material selection, ensuring that you get the best results for your specific requirements.
Choose Motorneo for precision-engineered laminations that elevate the efficiency and reliability of your electrical machines. Contact us today to discuss your project and get a competitive quote!
Conclusion
In conclusion, the lamination of the stator core is a vital aspect of electrical machine design and manufacturing. It offers advantages such as reduced losses, improved efficiency, enhanced performance, and noise reduction.
The choice of lamination materials and thickness should align with the specific requirements of the application. As the field of electrical engineering continues to evolve, so too will the techniques and materials used in stator core lamination.
Staying informed about emerging technologies and sustainable practices will be essential for those involved in the design and production of electrical machines.
By understanding the importance of stator core lamination, we can appreciate the role it plays in the reliability and efficiency of the electrical devices that power our modern world.
FAQS
Why are stator cores laminated?
Stator cores are laminated to reduce eddy current losses, improve efficiency, enhance performance, and reduce noise in electrical machines.
Can customize stator core lamination From China Manufacturer?
Absolutely, we specialize in providing customized rotor core laminations to meet your specific needs and requirements.
Whether you have unique size specifications, thickness preferences, or material requirements, our experienced team can work with you to create tailored solutions.
Feel free to reach out to us with your customization needs, and we’ll be more than happy to discuss your project, provide recommendations, and offer competitive pricing for your customized rotor core laminations.
What Is The Difference Between The Stator And Rotor Laminations In An Electric Motor?
We know what rotor and stator laminate are, so let’s dive into the key differences between stator and rotor of electric motors.
Location:
The stator core is located in the stationary part of the motor core, known as the stator. The stator surrounds the rotor and remains fixed in place.
Rotors are situated within the rotating part of the motor, which is the rotor. The rotor spins within the stator.
Function:
Stator laminations play a primary role in generating a rotating magnetic field when electrical current flows through the stator windings. This magnetic field interacts with the rotor to induce motion.
Rotor laminations serve to provide a magnetic path for the magnetic field generated by the stator. As the magnetic field rotates, it exerts a force on the rotor laminations, causing the rotor to turn and produce mechanical output.
Thickness:
The increased thickness helps stator laminations withstand higher mechanical loads as they remain stationary.
The rotor’s reduced thickness allows for efficient magnetic flux generation and response to the changing magnetic field from the stator.
Materials:
Stator motor laminations are typically made from the same material as rotor laminations, which are often silicon steel, cobalt, and nickel alloys. This material exhibits excellent magnetic properties and low electrical conductivity.
Rotor motor laminations also typically use high-grade silicon steel. The choice of silicon steel helps reduce core losses and enhances motor efficiency.
Shape:
Stators usually have a more complex and larger shape, as they need to surround the rotor and create a rotating magnetic field. The stator laminations are designed to accommodate stator windings and provide a path for the magnetic field.
Rotors tend to have simpler shapes, often circular or rectangular.
