Chapter 6 Control Modes of OperationASDA-AB Series

6.2.7 Timing Chart of Position (Pr) Control Mode

In Pr mode, position command source is DI signal from CN1, i.e. selected by POS0~POS2 and CTRG. Please refer to 6-2-2 to see the relationship between DI signals and parameters. The following figure is shown the timing chart of Pr mode:

Internal position

command

External I/O signal

P8

 

 

 

 

P3

 

 

 

 

P2

 

 

 

 

P1

 

1ms

 

 

 

 

 

 

POS0

OFF

ON

OFF

ON

POS1

OFF

 

ON

 

POS2

OFF

 

 

ON

CTRG

 

 

 

 

SON

ON

 

 

 

>2ms, can be set by P2-09

6.2.8 Position Loop Gain Adjustment

Before performing position control (setting position control block diagram), the users should complete the speed control setting by using Manual mode (parameter P-32) since the position loop contains speed loop. Then, adjust the Proportional Position Loop Gain, KPP (parameter P2-00) and Position Feed Forward Gain, PFG (parameter P2-02). Or use Auto mode to adjust the gain of speed and position control block diagram automatically.

1)Proportional Position Loop Gain: To increase this gain can enhance the position loop responsiveness.

2)Position Feed Forward Gain: To increase this gain can reduce the position track error during operation.

The position loop responsiveness cannot exceed the speed loop responsiveness, and it is recommended that the speed loop responsiveness should be at least four times faster than the position loop responsiveness. This also means that the setting value of Proportional Speed Loop Gain, KVP should be at least four times faster than Proportional Position Loop Gain, KPP.

The equation is shown as follows:

fp < fv

4 , fv : Speed Loop Responsiveness (Hz), fp : Position Loop Responsiveness (Hz)

KPP = 2 × π × fp.

6-10

Revision January 2009

Page 113
Image 113
Delta Electronics ASDA-AB manual Timing Chart of Position Pr Control Mode, Position Loop Gain Adjustment