Frequently Asked Questions

What is Axiom?

Axiom is a 3 phase motor controller based upon an open source platform, capable of driving very high power electric motors, like those found in modern electric vehicles.

 

What can I do with Axiom?

You can build extremely powerful one-off electric vehicles, and if you are a business, Axiom will greatly improve your supply chain by letting you modify the source code to fit your needs.

You can also use Axiom as a research tool for novel control algorithms or novel motor geometries.

Axiom is currently serving electric vehicle startups, research teams, individuals, aircraft and hvac companies.

Since the software is open source you can make any customizations needed to better fit your specific application.

 

Is Axiom control board available for sale?

We are currently in beta testing stage meaning control boards are available only to engineering teams with the capability of setting up a system quickly and provide quality feedback. We have boards populated and tested in stock for sale to beta testers, please contact us for pricing.

 

Can you sell a complete controller with powerstage included?

At the moment we only provide complete assemblies to big or very high impact companies. We provide 400V 300A assemblies using EconoDual modules, gate drivers, custom designed DC link capacitor, liquid cooled cold plate or air cooled heatsink. At the moment we don’t provide an enclosure.

 

When can I order a complete motor controller (Axiom control board + powerstage + active cooling and enclosure)?

We plan to sell assembled controllers next year.

 

Is there a datasheet available?

Yes, you can download the control board datasheet here:

 

Does Axiom come with a warranty?

No, Axiom should be considered an experimental motor controller. Please refer to the last page of the datasheet for the liability disclaimer.

 

If I order a control board, what parts are needed to run a motor?

An electric powerstage needs:

  • A battery (300Vdc to 400Vdc is best)
  • BMS
  • Fuse
  • Contactor
  • DC Link Pre-charge
  • DC Link capacitor
  • x6 IGBT modules and gate drivers
  • Liquid or air cooling
  • Torque command generator
    • Analog accel signal
    • CANbus accel commands
    • USB (not recommended for high power)
  • Motor position feedback
    • Resolver
    • Absolute encoder
    • Hall sensor (not recommended for high power)
  • A Permanent Magnet 3 phase motor

 

Why is it advised to use motor position feedback?

Because it’s difficult to validate that a sensorless algorithm will work under every operation condition.

Hall sensors are not advised because they only provide 120° resolution and still require an observer algorithm to infer the phase angle with <3° resolution.

 

Are resolvers supported?

Yes, they need some hardware tuning so the incoming signal is within hardware limits. See datasheet for more information.

 

What battery voltage is best for Axiom?

Anything between 50V and 420V will work, but IGBTs perform best at >300Vdc. With simple changes Vbus can reach 800V if needed.  Battery voltage above 800V maximum is not recommended.