Servosila-Device-Reference-0xA020192

Inertia (Rotor
and Payload)
Control (ESC) mode. If the moment of inertia is not measured correctly, the
electric drive might experience vibrations or noise whenever operated in a speed-
controlled mode. It is not required to be very precise in determining the moment
of inertia. It is enough to be "about right" since the control laws have significant
stability margins.
The controller can measure the Moment of Inertia directly. Note that before
invoking the procedure, one might have to measure "Viscous Damping
Constant", another "Datasheet" section's parameter.
The moment of inertia is automatically measured by the controller during an
auto-configuration procedure. In many cases, it is sufficient to just launch the
auto-configuration procedure that figures everything out. However, the
procedure assumes that Viscous Damping is not present. If that turns out to be
not the case, the auto-configuration procedure overestimates the moment of
inertia. This overestimation might lead to vibrations or noise in the drive,
whenever the drive is operated under Electronic Speed Control (ESC). In that
case, please refer to a tutorial that explains how to measure both Moment of
Inertia and Viscous Damping Constant together, and then rectify control laws.
The Moment of Inertia is needed to estimate an "ESC Kp" parameter of a control
law for Electronic Speed Control (ESC).
An initial value for the Moment of Inertia can be taken from the motor's
datasheet. The issue is that the datasheet provides the moment of inertia of the
motor's own rotor while what is needed is a combined moment of inertia of both
the rotor and its payload. Thus it is recommended to use the controller to directly
measure the combined moment of inertia instead of relying on the datasheet
value.
Typically, one would start commissioning a motor with a value taken from a
datasheet, and would come back later to refine the moment of inertia by
measuring it using the controller's built-in capabilities.
0x08,
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9 Hall Sensors 0 or 1 • 0: Sensorless
• 1: Sensored
The parameter "Hall Sensors" tells the controller whether or not the motor has
built-in Hall sensors. Many brushless motors come with Hall sensors. The
sensors help the controller improve an electric drive's performance at low or zero
speeds.
NOTE: Both this parameter and a corresponding section "Peripheral: Hall
Sensors" are automatically configured by the controller's auto-configuration
procedure. Typically, one would not edit these manually.
An advantage of having Hall sensors is that the motor works in a much more
stable way at low or zero speeds as compared to "sensorless" motors. With Hall
sensors, the motor can produce torque at zero speed or whenever the motor is
BOOL,
0x2000,
0x09,
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