Axial Flux Motor Sizes: Small, 10 kW and 100 kW Explained
By the Turncircles engineering team · Published
People search for "10 kW axial flux motor", "100 kW axial flux motor" and "small axial flux motor" as if power were a size. It is not: a motor's size follows from torque, and power only tells you torque if you also say at what speed. Here is how to read the size classes, with the arithmetic shown.
And we will be straightforward about our range: it covers small and 10 kW motors comfortably, and a true 100 kW motor is a conversation, not a checkbox.
Size your motor in the configurator Use the power-torque-speed converterPower Is Torque Times Speed
"Small", "10 kW" and "100 kW" are descriptions of power, and power says very little about a motor on its own. A motor delivers power as torque multiplied by angular speed: P = T × ω, with ω in radians per second, or P = T × RPM × 2π / 60. The same 10 kW can be 16 Nm at 6,000 RPM or 64 Nm at 1,500 RPM, and those are very different motors.
| Power | Speed | Torque needed |
|---|---|---|
| 1 kW | 3,000 RPM | 3.2 Nm |
| 10 kW | 6,000 RPM | 15.9 Nm |
| 10 kW | 3,000 RPM | 31.8 Nm |
| 10 kW | 1,500 RPM | 63.7 Nm |
| 56 kW | 6,000 RPM | 89 Nm |
| 100 kW | 6,000 RPM | 159 Nm |
| 100 kW | 3,000 RPM | 318 Nm |
Torque is what an axial flux motor is good at, since it scales with the cube of the radius. Speed is what the electronics and the rotor strength limit. Hence the first question about any size class is always: at what speed?
What Our Range Covers
The platform scales in two directions: diameter from 60 mm to 406 mm, and stacks, which add torque and power without growing the footprint. At the top of the range that gives nominal torque up to 24 Nm per stack, up to 100 Nm with several stacks, nominal speed up to 6,000 RPM, supply up to 370 VDC and power up to 56 kW. Note the match with the table above: 56 kW at 6,000 RPM needs 89 Nm, inside the 100 Nm multi-stack limit.
Maximum values of the platform, not one motor. The configurator shows what your own specification delivers.
Small Axial Flux Motors
Small is where a flat disc is most welcome: drone propulsion, gimbals, robot joints, pumps, wheelchairs. The homepage configurator shows one realistic starting point, a 125 mm single-stack motor delivering 350 W at 1.55 Nm. The diameter can go down to 60 mm. At that size the main design questions are weight, heat removal from a small surface and how the motor is mounted, which is why naked motors are popular here: the structure of your machine is the housing.
The 10 kW Class
Ten kilowatts is a comfortable size for an axial flux motor, and it is inside the configurator range. What changes compared with small motors is the electrical side. At 48 V, 10 kW is more than 200 A, which is a thick-cable, serious-contactor problem. At 96 V it is about 100 A, and at 370 V about 27 A. Pick the supply voltage together with the motor, not after it, and let the winding follow. This is exactly the kind of choice the configurator exposes, because the winding is one of its parameters.
Mechanically, 10 kW at 3,000 RPM needs about 32 Nm. That is more than a single stack of 24 Nm, so expect either two stacks or a larger diameter. Cooling becomes a real design item at this size: a wet or fluid-cooled design can lift the continuous rating.
The 100 kW Class: An Engineering Conversation
One hundred kilowatts is beyond what the configurator covers today, which tops out at 56 kW. We could squeeze the number into a sales page, but you would be right not to trust it. At 6,000 RPM the torque requirement is 159 Nm, above the multi-stack limit, and at lower speeds it quickly passes 300 Nm.
What we can say honestly: the physics still favours axial flux at high torque, because the radius is the lever. What changes is the engineering around it: the thermal design, the supply voltage and current, the mechanical structure, and whether the power is better split between several motors. If you have a 100 kW requirement, talk to us and bring your duty cycle. We will tell you what is realistic, including when the answer is that someone else makes a better fit.
Frequently Asked Questions
How much power can an axial flux motor produce?
Power is torque times speed, so it depends on size and speed. Turncircles configurable motors cover up to 56 kW with nominal torque up to 24 Nm per stack (100 Nm multi-stack) at up to 6,000 RPM.
What size is a 10 kW axial flux motor?
It depends on speed. 10 kW at 6,000 RPM needs about 16 Nm; at 3,000 RPM about 32 Nm. That is typically one to two stacks in the Turncircles range, with a diameter chosen for the thermal and torque requirement.
Do you make a 100 kW axial flux motor?
It is above the configurator range of 56 kW, so it is an engineering project rather than a configuration. Contact us with your torque, speed and duty cycle, and we will say what is realistic.
What is the smallest axial flux motor you can make?
The configurator covers outer diameters from 60 mm. Torque and power at that size are small by design; the configurator shows the numbers for your inputs.
How do I convert kW to Nm?
Torque in Nm equals power in watts divided by angular speed in radians per second, or T = 9.549 × P / RPM with P in watts. The power, torque and speed converter does it for you.
Start from your torque and speed
The configurator turns them into a motor and shows what it delivers.
Configure your motor Talk to an engineer