Application note Minimum settling time for high-rate

Minimum settling time for high-rate indexing The “Minimum settling time” feature on the Auto-tuning function allows to fulfil these applications requirement. This document describes the servo loop adjustment for getting the shortest position loop response time. An application example is also given.

Minimum settling time for high-rate indexing 2 -AUTO-TUNING WITH “MINIMUM SETTLING TIME” SELECTION Select “Minimum settling time” in the controller window, then start Auto-tuning. After the Auto-tuning execution, adjust the Bandwidth level and the Tuning level on-line with the motor enabled to optimize the servo loop stability and dynamic. Auto-tuning with “Minimum settling time”

Minimum settling time for high-rate indexing 3 - FEEDFORWARD GAINS MANUAL ADJUSTMENT FOR MINIMUM SETTLING TIME A manual adjustment of the feedforward gain values (KFv and KEv) allows to optimize the servo loop response settling time. This manual adjustment process is described below. Remark: If the tuning level is changed after a manual adjustment, the manual adjustment will be lost because all controller gains are set according to the new tuning level value. 3.1 - INFLUENCE OF KFV Start first with KFv only (KEv set to 0) to reduce the position error settling time. The influence of KFv gain value...

Minimum settling time for high-rate indexing 3.2 - INFLUENCE OF KEV When KFv gain has been adjusted, adjust then the KEv gain to further reduce the position error settling time. The influence of KEv gain value on the position error response is shown below . Feedforward gains manual adjustment for minimum settling time

Minimum settling time for high-rate indexing OINFRANOR Indexing application as shown below requires fast movement execution and short servo loop response time, to reduce the axis positioning cycle and increase the machine feed rate. At the end of the movem ent the axis must be in position (+/- 2 inc) as fast as possible for the process operation (20ms duration) during the rest time. If the rest time duration must be increased for the process operation, the indexing rate is not fulfilled. Minimum following error Operation mode Position loop requirements Autotuning mode [Standard mode Filter type...

Minimum settling time for high-rate indexing OINFRANOR Operation mode uence mode Position loop requirements Minimum position overshoot Autotuning mode Stan said inode Filter type Max st ffness START AUTO-TUN NG Time base = 12.5 ms/DIV - Delay = 50 ms Time between T1 and T2 cursors: dT = 23.51 ms Channel 1 = VelRef (Qx30F8,0x01) on ttrapulsPacHP ET 400V 45A (NodelD 2) (Range = 100 rpm/DIV, Offset = 0) Value(T1)=0 rpm Channel 2 * VelFb (0x3OF8,Qx02)on ttrapulsPacHP ET400V 45A (NodelD 2) (Range = 100rpm/DIV, Offset * 0) Value(T1)=33,69 rpm Channel 3 = Idc (Qx30F8.0x04) on XtrapdsPacHP ET 400V 45A...

Minimum settling time for high-rate indexing OINFRANOR Time base = 12.5 ms/DIV - Delay = 50 ms Time between T1 and T2 cursors : dT = 6.37 ms Channel 1 * VelRef (Qx30F8.Qx01) on XtrapulsPacHP ET 400V 45A (NodelD 2) (Range * 100 rpm/DIV. Offset * 0) 'alue(T1)=0t14 rpm Channel 2 = VelFb (Gk30F8.0k02) on XtrapulsPacHP ET 400V 45A (NodelD 2) (Range = 100 rpm/DIV. Offset = 0) Value(T1)=21.48 rpm Channel 3 = Idc (0x3OF8.0xO4) on JQrapulsPacHP ET 400V 45A (NodelD 2) (Range * 10 A/DIV. Offset = -20) Value(T1)=-2.62 A Channel 4 = PosErr (Qx60F4.0xOO) on XtrapulsPacHP ET 230V 17A (NodelD 2) (Range * 10...

Minimum settling time for high-rate indexing 5 -CONCLUSION The “Minimum settling time” selection on the Auto-tuning function allows to get a very short position loop response time. This feature allows to fulfil the requirements of high-rate indexing application.