01
Battery window before nominal voltage
Specify minimum loaded voltage, nominal voltage and maximum charged voltage, plus regeneration limits. A label of 48 V alone does not define the inverter voltage class or available loaded speed.
CUSTOM MOTOR DEVELOPMENT / OEM & R&D
48–96 V axial flux motors. Start with current and duty.
48–96 V DC / 5–30 kW inquiry targets
For OEM teams developing mobile machinery, compact vehicles, heavy UAVs or marine prototypes, a thin motor package is only one constraint. Bring the battery window, load cycle and cooling budget together before choosing a winding or inverter.
THE PROGRAM STARTS HERE
Resolve the constraints that change the design.
02
Continuous duty before a peak number
State the torque–speed points and time at each point, including starting, hill holding, take-off or bollard pull. Agree peak duration, initial temperature and recovery time separately.
03
Match the complete drive
Review phase current, back-EMF, pole pairs, position feedback and the intended control method with the inverter supplier. Motor, cable, connector and battery current limits belong in the same review.
INPUTS / INTERFACES / OWNERSHIP
Build a usable operating envelope.
These are the decisions to scope before a quotation. Feasibility, engineering deliverables, sample cost, tooling and recurring production terms follow the agreed requirements.
| Input | What to provide | What the review resolves |
|---|---|---|
| DC supply | Minimum / nominal / maximum voltage under load | Winding and inverter operating window; regeneration headroom |
| Mechanical output | Continuous and timed peak torque at stated rpm | Electromagnetic loading and thermal duty; no rating inferred from kW alone |
| Current budget | Battery DC limit and inverter phase RMS / peak limits | Separate supply, winding, interconnect and drive constraints |
| Package | Outer diameter, axial length, shaft, mounting and load direction | Housed motor versus frameless kit; bearing and integration ownership |
| Cooling | Airflow or liquid type, inlet temperature, flow and pressure budget | Heat path and test boundary; auxiliary cooling hardware scope |
| Environment | Ambient, vibration, contamination, splash and corrosion exposure | Protection requirements and a project-specific verification plan |
WORKED EXAMPLE / ASSUMED INPUTS
Why doubling voltage changes the supply discussion
Illustrative calculation only: assume 10 kW shaft output and 90% combined motor-and-inverter efficiency at that operating point. Required DC input is about 11.11 kW. At a loaded 48 V the average supply current is about 231 A; at 96 V it is about 116 A.
I_DC = P_shaft / (η_drive × V_DC)
The 90% value is an assumed example, not measured performance. These are average DC currents, not phase RMS currents. Voltage sag, ripple, transients and thermal limits still require a drive review.
APPLICATION-SPECIFIC DUTY
Bring the load case behind the power number.
AGV & off-highway
Bring wheel force, reduction ratio, starts per hour, stall or holding periods and ambient temperature. Repeated low-speed torque can govern the design even when average power is modest.
Heavy UAV research
Separate take-off and cruise points, propeller inertia and thrust loads. Include vibration and loss-of-cooling cases. Any flight qualification remains a separate program with the responsible integrator.
Electric marine prototypes
Specify continuous propeller duty, shaft loads, coolant source, salt exposure and enclosure needs. A water-cooled design does not by itself establish immersion or corrosion performance.
AGREE ACCEPTANCE BEFORE SAMPLES
Request the evidence for your operating point.
- A winding-specific torque–speed envelope with DC voltage and inverter current conditions.
- A timed thermal run with temperature locations, coolant or airflow conditions and derating behavior.
- Phase resistance, insulation and feedback checks using agreed methods and limits.
- Assembly clearances, rotor retention, balance and bearing loads tied to the controlled build.
- Drive commissioning scope, interface files and the party responsible for system-level release.
START WITH A NON-CONFIDENTIAL BRIEF
Discuss your 48–96 v motor programs.
Send the requirements and quantities first. Request an NDA before sharing detailed proprietary CAD. The review defines feasibility, deliverables and responsibilities before pricing or timing is confirmed.
- Loaded DC voltage window and battery current limit
- Continuous and peak torque / rpm / duration
- Available diameter, length, shaft and mounting drawing
- Cooling and environmental conditions
- Inverter model, feedback preference and sample / annual quantities
Start your engineering brief.
Use the inquiry form, or contact us directly with your duty cycle, package, cooling and quantity requirements.
ENGINEERING & PROCUREMENT
Questions before a motor RFQ.
Is there a stocked 10 kW or 30 kW motor?
This page opens a custom engineering inquiry. The 5–30 kW band is a target scope, not a catalogue of released models. Availability, price, drawings and delivery dates require a project review.
Can the same motor run at both 48 V and 96 V?
Possibly within a reviewed operating envelope, but the same torque, speed and continuous output cannot be assumed at both voltages. Winding back-EMF, inverter limits, maximum speed and thermal loading must be checked.
Does DC supply current determine the inverter phase rating?
No. DC input current describes supply power; phase current is tied to the winding and torque production. The relationship varies with operating point and switching. Provide both limits with RMS or peak definitions.
Can you review a frameless rotor–stator kit?
Yes, select a kit scope in your project summary. Define who owns bearings, housing, alignment, retention, cooling and final assembled testing before comparing kit and complete-motor quotations.
Is a controller included?
A drive system can be discussed, but no controller is included by default. Compatibility requires the exact voltage window, current definitions, motor constants, feedback and commissioning responsibilities.
What determines NRE and sample pricing?
Winding and electromagnetic changes, mechanical tooling, materials, assembly fixtures, test scope, quantity and documentation all affect cost. A quote should separate development, tooling, samples and recurring units.