WHL-500

Fully integrated reaction wheel unit for high performance satellite attitude control for Micro satellite missions with mission lifetime up to 5 years (minimum).

The WHL-500 wheel is an integrated 3-phase outrunner permanent magnet synchronous motor (PMSM) with fully integrated motor control electronics and software. Material for the body is Al-7075-T6, and the rotor is made of ferritic stainless steel while the magnets are Neodymium. The rotor is axially suspended between two hybrid ceramic high precision bearings chosen for long life and low friction in vacuum conditions. The wheel is commutated by its own internal microcontroller, which runs the control loop to control speed and acceleration upon commands from the ADCS computer.

Each wheel has a CAN bus interface with CSP making them accessible to the satellite communication bus. The wheels are fitted with basic telemetry sensors: Temperature, current, speed, vibration. Software can be updated runtime with only a few seconds idle spinning.

For reliability, the stator incorporates redundant wiring which is complemented by redundant drive stage electronics. The internal power supplies add latch-up protection as well as over-current protection to all the circuits.