User Manual

Closed Loop Torque Mode
162 Advanced Digital Motor Controller User Manual V2.0 July 8, 2019
Torque Mode Selection, Configuration and Operation
Use the PC utility and the menu “Operating Mode” to select Torque Mode. The controller
will now use user commands from RS232, RS485, TCP, USB, Analog or Pulse to command
the motor current.
Torque commands can be given:
• G command, with range -1000 to +1000. The command for brushed controllers is
then scaled using the amps limit configuration value. For example, if the amps lim-
it is set to 100A, a user command of 500 will cause the controller to energize the
motor until 50A are measured. For brushless controllers and in sinusoidal mode,
the G command is scaled based on the torque (quadrature) amps limit. If flux amps
are always at 0 (no field weakening) then the scaling is the same.
• TC command, which is similar to G command but the command is given in
Nm*100. The torque constant TNM is used in order to translate the torque com-
mand to current command.
• GIQ command (applicable only for brushless motor controller and sinusoidal mode),
with which one can give the Torque (quadrature) amps command in Amps*10.
• GID command (applicable only for brushless motor controller and sinusoidal mode),
with which one can give the Flux amps command in Amps*10.
Torque Mode Tuning
In Torque Mode, the measured Motor Amps become the feedback in the closed loop sys-
tem. The PID then operates the same way as in the other Closed Loop modes described
in this manual (See “PID tuning in Position Mode” on page 148).
In most applications requiring torque mode, the loop response does not need to be very
quick and good results can be achieved with a wide range of PID gains. The P and I gains
are the primary component of the loop in this mode. Perform the first test using P=0, I=1
and D=0, and then adjust the I and P gain as needed until satisfactory results are reached.
In brushless controllers, torque mode uses the PID that is regulating the Field Oriented
Control. The gains must be therefore set in the FOC menus. See also the KIF and KPF
configuration commands in the Commands Reference section.
Configuring the Loop Error Detection
In Torque Mode, it is very likely that the controller will encounter a situation where the
motor is not sufficiently loaded in order to reach the desired amps. In this case, controller
output will quickly rise to 100% while a significant Loop Error (i.e. desired amps - mea-
sured amps) is present. In the default configuration, the controller will shut down the
power if a large loop error is present for more than a preset amount of time. This safety
feature should be disabled in most systems using Torque Mode.