Servosila-Device-Reference-0xA020192

with a tool that helps with that.
To summarize, as the Back-Emf Constant (Ke) is something that can be easily
misunderstood or misconfigured, it is better to rely on the controller's own
capabilities to properly measure and auto-configure the parameter.
7
Payload:
Viscous
Damping
Constant
Nm/
Hz
Viscous damping refers to forces of friction that are proportional to the motor's
speed of rotation. An example of viscous damping would be water giving
mechanical resistance to a pump's motor. Note that viscous damping refers to
forces originated in both the motor and its payload, rather than just in the motor.
This means that the parameter needs to be determined experimentally, rather than
taken from the motor's datasheet.
If Viscous Damping is not a concern, set the parameter's value to 0, and just
proceed with commissioning the motor.
There is an experimental procedure that allows measuring the Viscous Damping
Constant using the controller's built-in capabilities.
The controller expects that the Viscous Damping Constant is provided in
"Newton-Meters per Electrical Revolution per Second (Hz)" units.
The Viscous Damping Constant is used by the controller in the following ways:
• Feed-Forward Optimization: Viscous Damping Compensation for
Electronic Speed Control and Servo Control.
• As an input into a procedure that measures "Moment of Inertia of Rotor
and Payload".
A Feed-Forward Optimization called "Viscous Damping Compensation"
improves the dynamics and efficiency of an electric drive in case the drive
experiences much viscous damping. The optimization can be enabled once the
Viscous Damping Constant has been measured using an experimental routine. By
default, the optimization is turned off, and thus the constant is not used for
anything other than as an input into a procedure that measures "Moment of
Inertia of Rotor and Payload".
To properly measure "Moment of Inertia of Rotor and Payload", another
parameter in this section, using the controller's built-in capabilities, one first
needs to properly measure "Viscous Damping Constant".
Typically, one would initially leave the Viscous Damping parameter as 0,
complete the first pass of the configuration, and later come back to the parameter
to measure it, refine the configuration, and enable an optimization feature that
utilizes the parameter.
FLOAT32,
0x2000,
0x07,
rw
8 Payload:
Moment of
kg*m
2
The "Moment of Inertia of Rotor and Payload" parameter is used by the
controller to determine parameters of control laws related to Electronic Speed
FLOAT32,
0x2000,
7 www.servosila.com