Influence Of Stator Segmentation On Iron Losses In PMSMs

Ever wondered how the intricacies of stator design can significantly impact the efficiency of electric motors, especially in the context of traction applications? The journey into the world of motor optimization brings us to a pivotal question: How does stator segmentation influence iron losses in Permanent-Magnet Synchronous Motors (PMSMs) designed for traction applications? In this paper, we investigate and discuss the realm of stator segmentation, conducting a detailed analysis of its influence on total iron losses.

We aim to unravel the differences in this crucial aspect of motor design, comparing various segmentation methods under equal excitation conditions.

Stator Segmentation

Silicon Steel Segmented Laminations Bonding And Stacking

Stator segmentation is a design technique that involves dividing the stator winding into distinct segments.

Segmented stators are usually made of electrical steel. These segments can be achieved through various methods such as full-pitched windings, fractional slot windings, and concentrated windings.

A variety of motor topologies including laminated-core surface-mounted or interior permanent magnets with distributed or concentrated winding are studied and considered.

Each technique has its unique advantages and disadvantages, influencing the motor’s overall efficiency and performance.

Full-pitched windings, for instance, involve winding coils that span the full pitch of the stator. Fractional slot windings, on the other hand, divide the stator into fractional slots, providing more design flexibility. Concentrated windings concentrate the coil turns in specific slots, enhancing certain motor characteristics.

Iron losses in the stator core for PMSMs

Key variables such as copper fill factors, cut edge precision, homogenized airgap length, magnetic flux density, and segmented stator winding fill factors are integral components in the pursuit of optimizing motor performance.

Copper fill factors, defining the volume of copper within stator slots, effect the motor’s conductive efficiency.

The cut edge precision, a geometric parameter, shapes the magnetic flux distribution, directly impacting iron losses. Precise engineering of the cut edge is fundamental for minimizing energy dissipation. The segmentation of the stators creates additional air gaps and changes the soft magnetic material’s material properties due to the cut edge effect.

Obtaining a homogenized airgap length is essential to control variations in magnetic circuits. Consistent airgap lengths contribute to the reduction of iron-loss, enhancing overall motor efficiency.

The winding fill factor, representing the ratio of actual copper area to total slot area, plays a pivotal role in optimizing the motor’s winding efficiency. Striking the right balance in winding fill factors is key to minimizing energy losses and maximizing motor efficiency.

spliced stator lamination stacks

The Relationship Between Stator Segmentation and Iron Losses

The interaction between stator spliced tooth and iron losses is a key factor in motor design. Segmentation changes the distribution of magnetic flux within the stator, influencing the magnitude and distribution of iron losses.  

Research indicates that combined hysteresis model design, finite element analysis, and IMs per pole magnetic flux calculate can help mitigate iron losses, improving overall motor efficiency.

Comparative studies reveal that motors with segmented stators experience lower iron losses compared to their non-segmented counterparts. The segmentation optimizes the magnetic field, reducing energy dissipation as heat.

Optimization Techniques for Minimizing Iron Losses

To minimize iron losses, motor designers employ various optimization techniques. Stator segmentation emerges as a crucial tool in this process.

By strategically implementing segmentation, motor designers can achieve a balance between reduced iron losses and other performance metrics.

Stator segmentation not only contributes to lower iron losses but also increases motor performance in terms of power density and torque characteristics.

Applications in Traction Systems

Stator core segmentation is particularly useful in traction systems, such as those found in electric and hybrid vehicles, due to their efficiency and performance benefits. The reduction in iron losses achieved through segmentation directly impacts the vehicle’s range, hub rotational speed, and overall efficiency.

Segmented stators can reduce manufacturing complexities and improve motor efficiency by minimizing losses due to eddy currents and enhancing cooling capabilities.

Our Segmented Stator Lamination Capabilities

Motorneo produces electrical laminations and lamination segments ranging from 20 mm to 1250 mm in diameter.

Having multiple 25T-300T punching machines to mass production motor lamination stacks.

For lamination prototyping, we offer laser cutting and wire cutting(low-speed, medium-speed, and high-speed) to rapidly cut electrical steel lamination.

Segmented stator laminations use 0.1mm – 1mm silicon steel and 25μm amorphous materials.

Our expertise source lies in various segmentation methods, namely full-pitched windings, fractional slot windings, and concentrated windings.

Partner with us for an integration of technology and craftsmanship, redefining the benchmarks for segmented stator laminations in the realm of single or three phase electric motor design.

our segmented stator lamination stacks capabilities


In conclusion, the influence of stator segmentation on iron losses in PMSM is a critical aspect of motor design, especially in traction applications. By understanding the relationship between stator segmentation and iron losses, motor designers can optimize performance, and improve efficiency.

The segmentation in most cases slightly decreases the iron losses in the stator because of the overall reduced magnetic flux density B due to the additional air gaps in the magnetic circuit. An increase in the individual components, as well as total power loss, was observed in the Pole Chain segmentation design. In general, segmentation did not change the total iron losses significantly.


In what ways does stator segmentation improve the efficiency of electric motors used in traction applications?

Stator segmentation improves efficiency by minimizing iron losses, optimizing magnetic flux distribution, and enhancing overall motor performance in traction-driven systems.

How does the iron loss reduction achieved through stator segmentation translate into benefits for electric vehicles?

The reduction in iron losses directly contributes to improved energy efficiency, extended battery life, and enhanced overall performance in electric vehicles.

What is the purpose of segmenting stator laminations in electric motor design?

Segmenting stator laminations in electric motor design serves the purpose of optimizing magnetic flux distribution and minimizing energy losses.

This precision engineering technique involves dividing the stator into distinct segments, allowing for more efficient control of the magnetization and demagnetization processes.

By strategically managing the distribution of magnetic flux, segmented stator laminations contribute to reduced iron losses and enhanced overall motor efficiency, making them a vital element in the quest for high-performance and energy-efficient electric motors.

Try to contact us for high-quality motor cores in China.