Determining The Coefficients - Addi-Data CPCI-8004 Commissioning Manual

CM / C M 59
OMMISSIONING ANUAL

6.2.5.1 Determining the coefficients

To determine the pre-control coefficients experimentally, first run a short trapezoidal profile, and use the
graphical system analysis to assess it, in order to set suitable profile data and scaling parameters. Run the
profile with medium acceleration and velocity. The acceleration ramp, deceleration ramp and linear
traversing range should be more or less evenly distributed on the screen and displayed in full. The control
algorithm is then deactivated by resetting the kp, ki and kd parameters. The pre-control parameters can now
be modified until the setpoint and actual speed characteristics coincide in good approximation after the
preset profile has been run. After every modification to the parameters, you must select the [Clear Position]
and [Update Filter] menu items, so that the new parameters can be applied.
When using a current amplifier, first set the acceleration pre-control kfca so that the acceleration ramps for
the setpoint and actual speed coincide. Then set the velocity pre-control so that the speed in the linear
speed range runs parallel. Now both values can be slightly altered alternately until setpoint and actual speed
characteristics best coincide.
When using a speed controller, begin with the velocity pre-control kfcv.
After the best possible parameters have been found, the kp, ki and kd filter parameters are entered again
and the behaviour is checked again. Ensure that the data you have set is saved.