Setting
up Compax3
Positioning via digital I/Os
122
192-120101 N11 C3I11T11 November 2007
4.4.3.2
Configuration
In this chapter you can read about:
Control path .....................................................................................................................................122
Motor parameters relevant for the control........................................................................................123
Mass inertia .....................................................................................................................................123
Nominal point data...........................................................................................................................123
Saturation values .............................................................................................................................125
Quality of different feedback systems..............................................................................................125
Typical problems of a non optimized control ...................................................................................126
Feedback error compensation .........................................................................................................127
Commutation settings ......................................................................................................................129
I²t - monitoring of the motor .............................................................................................................129
Relevant appication parameters ......................................................................................................132
Control path
For the motors, the knowledge of the mathematical model is a prerequisite.
Mathematically idealized model of the control path:
R
/
1
T
K
T
K
π
2
π
2
1
U:
Cotrol voltage
U
EMC
:
electromagnetically generated voltage in the motor
T:
electric time constant of the motor winding
L: Winding
Inductance
R: Winding
Resistance
M
A
:
Drive torque of the motor
M
L
: Load
torque
M
B
: Acceleration
torque
I:
Actual current r.m.s. (torque-producing)
K
T
: Torque
constant
J
mot
:
Motor mass moment of inertia
J
ext
:
External mass moment of inertia
J
total
:
Total mass moment of inertia
a: Acceleration
n: Velocity
