Stator winding design rarely gets the spotlight it deserves.
In most motor discussions, attention gravitates toward magnets, control algorithms, or headline torque figures. Yet in practice, the way a stator is wound—distributed or concentrated—plays a decisive role in how a motor behaves across efficiency, smoothness, noise, thermal stability, and manufacturability.
As motion systems move toward higher precision, smaller envelopes, and longer duty cycles, the choice between distributed winding and concentrated winding is no longer a theoretical discussion. In 2026, it is a practical engineering decision that directly affects system performance and production reliability.
This article explains the core differences between distributed and concentrated stator windings, how each evolved, where engineers often misunderstand them, and how experienced teams choose between the two in modern applications.
What Is Stator Winding and Why It Matters More Than Ever
The stator winding is the electromagnetic heart of an electric motor. Its geometry determines how magnetic fields are generated, how torque is produced, and how smoothly that torque is delivered to the rotor.
In earlier industrial eras, winding design was often constrained by manufacturing limitations. Today, with improved winding equipment, simulation tools, and tighter system-level requirements, winding topology has become a deliberate design lever rather than a default choice.
By 2026, the rise of precision equipment, medical devices, collaborative robotics, and compact automation has pushed winding design back into focus—especially the trade-off between distributed and concentrated windings.
Understanding Distributed Stator Windings
Distributed winding is the traditional approach used in many AC and BLDC motors.
Instead of grouping all turns of a phase into a single tooth or slot, the coils are distributed across multiple stator slots. Each phase overlaps spatially with others, creating a smoother and more sinusoidal magnetic field around the air gap.
![85mm distributed winding stator (2)]( "85mm distributed winding stator (2)")
Key Characteristics of Distributed Windings
Distributed windings are known for:
These characteristics make distributed windings especially suitable for applications where motion smoothness and acoustic performance are critical.
Why Distributed Windings Became the Industry Baseline
Historically, distributed windings aligned well with grid-powered AC motors and later translated naturally into early BLDC motor designs. Their electromagnetic behavior is forgiving, and small variations in winding placement tend to average out across multiple slots.
For many years, this made distributed windings the safest and most widely adopted option.
Limitations of Distributed Windings in Modern Designs
Despite their advantages, distributed windings are not universally ideal—especially in compact or cost-sensitive systems.
End-Winding Length and Copper Utilization
Distributed windings often require longer end windings. This increases copper usage, electrical resistance, and heat generation, particularly in small frame sizes.
As systems shrink, these inefficiencies become more noticeable.
Manufacturing Complexity
Distributed windings are generally more complex to manufacture. Automation is possible, but tooling, setup, and quality control become more demanding at scale.
For medium-volume production runs, this complexity can impact cost predictability and lead times.
Understanding Concentrated Stator Windings
Concentrated windings take a fundamentally different approach.
Each phase winding is concentrated around a single tooth or a small group of teeth. The coils do not overlap across the stator circumference in the same way distributed windings do.
This results in a more compact and modular winding structure.
![concentrated winding stator]( "concentrated winding stator")
Key Characteristics of Concentrated Windings
Concentrated windings are valued for:
Shorter end turns
Higher copper fill factor
Lower copper losses in compact motors
Simpler and more scalable manufacturing
Because copper is used more efficiently, concentrated windings often achieve higher torque density in small motors.
Why Concentrated Windings Gained Popularity After 2020
The growth of compact BLDC motors, slotless motors, and integrated drive systems accelerated the adoption of concentrated windings.
As OEMs pushed for smaller footprints and lighter assemblies, the electrical efficiency gains from shorter end windings became increasingly attractive.
In addition, concentrated winding architectures align well with modern automated winding equipment, reducing variability in medium-scale manufacturing—an area where engineering-driven suppliers such as Modar Motor have quietly built advantages.
The Trade-Off: Torque Density vs Torque Quality
At the heart of the distributed vs concentrated discussion lies a fundamental trade-off.
Torque Ripple and Harmonics
Because concentrated windings create more localized magnetic fields, they tend to introduce higher harmonic content into the air-gap flux. This can result in increased torque ripple, vibration, and audible noise if not carefully managed.
Distributed windings naturally mitigate these effects through spatial averaging.
Thermal Behavior: Often Overlooked, Always Critical
Thermal performance is one of the most misunderstood aspects of winding selection.
Concentrated windings localize heat more strongly. While shorter copper paths reduce resistive losses, heat can accumulate around individual teeth if thermal paths are poorly designed.
Distributed windings spread heat more evenly but generate more total heat due to longer copper lengths.
In 2026, engineers increasingly evaluate winding designs together with housing materials, potting strategies, and duty cycles rather than in isolation.
Control Strategy Interaction
Winding topology directly affects control behavior.
Motors with distributed windings often produce smoother back-EMF waveforms, simplifying control and reducing sensitivity at low speeds.
Concentrated winding motors may require more attention in control tuning, particularly in precision or low-speed applications. However, modern controllers and improved winding symmetry have significantly narrowed this gap.
Where Slotless Motors Fit into the Discussion
Slotless motors introduce a hybrid perspective.
Most brushless slotless DC motors use distributed winding principles without stator teeth, eliminating cogging torque almost entirely. This makes winding quality and symmetry even more critical.
In such designs, the distinction between distributed and concentrated concepts shifts from slot geometry to coil distribution and magnetic uniformity—areas where manufacturing expertise matters more than textbook definitions.
Common Engineering Mistakes When Choosing Winding Types
Several recurring mistakes appear across projects:
Choosing concentrated windings solely for torque density without evaluating vibration impact
Assuming distributed windings are always quieter without considering mechanical integration
Ignoring manufacturing repeatability in medium-scale production
Treating winding choice as independent from thermal and control design
Teams that revisit these assumptions early typically avoid late-stage redesigns.
How Experienced Teams Make the Decision in 2026
By 2026, winding selection is rarely reduced to “better or worse.”
Instead, experienced engineers ask:
What matters more: smoothness or compactness?
Is the application speed-dominant or torque-dominant?
How sensitive is the system to vibration and noise?
What manufacturing volume and consistency are required?
Suppliers with strong engineering communication—rather than purely catalog-driven offerings—tend to perform better in this decision-making process. This is where companies like Modar Motor are often involved early, not to push a winding type, but to align it with the actual application constraints.
Final Thoughts: Winding Design Is a System Decision
Distributed and concentrated stator windings are not competing technologies. They are tools.
Used appropriately, each delivers excellent performance. Used blindly, each can introduce unnecessary limitations.
As motors become more integrated, compact, and application-specific, winding design moves from the background to the foreground of engineering decisions.
In 2026, understanding stator winding topology is no longer optional knowledge. It is foundational—and often the quiet difference between a motor that merely meets spec and one that performs reliably in the real world.
