74
9) Run the car up and down a few times. Note that during the acceleration,
the same value should be reached and then a much lower value during
the constant speed portion of travel. Disregard the values during
deceleration.
10) After having gotten a sense of the values, it will now be necessary to write
down the values after each run. The values to note are the value during
acceleration in the up direction and the value at constant speed in the up
direction. It does not matter whether they are positive or negative. Write
them all down as a positive value. Get values from about ten runs.
11) Add all acceleration values together and divide by 10. Add all constant
speed values together and divide by 10. Then subtract the constant speed
value from the acceleration value. The result is the value you need.
12) With the car standing still, press the Enter key on the keypad of the drive.
The display will show VALuE. Press the up arrow key and scroll up to the
value from step 11.
13) Once the value is correct, press Enter. This stores the acceleration torque
value in parameter Ld.29. Additionally this calculates the system inertia
and sets up the feed forward control in parameters Ld.30...Ld.32.
14) At this point the drive is back to normal run mode. The car should
accelerate normally. In the controller, readjust the speed (tach) following
error to a more normal value.
15) The process can be repeated starting from step 6.
1) Now that the inertia is set, the FFTC is active. The effectiveness of the
control can be simply in uenced by the gain value in parameter Ld.32.
90% is the typical value which should give good results. However, if the
value is lowered, the in uence of the FFTC will be reduced, higher values
will intensify the result. Values in the range 50% to 150% can be typical.
Setting this value to 0% turns off the FFTC.
2) With the FFTC turned on it is possible to reduce the values of A.LF.31,
d.LF.31, A.LF.32, d.LF.32, although, it is not always necessary.
3) Depending on the type of elevator, geared or gearless, more or less offset
gain (LF.33) may be required.
5.12.2 Feed Forward
Torque Control, FFTC
Initial Start Up
To Next Page
Loading...
Need help?
General