Vector VEC-VA Series, Programming Manual

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VA Motion Controller Programming Manual
546
dead band) represents a set value in the
PID
operation is not
performed;
MaxError
(maximum
cumulative
error) The maximum cumulative
error
LREAL Real -
CycleTime
(PID sampling
period)
PID sampling cycle unit
(ms)
LREAL Real -
Description:
1) PID control principle
PID regulation is Proportional (ratio), Integral (Integral), abbreviation Differential
(differential) of the three, is the most widely used system of continuous adjustment method. The
essence of PID regulator, according to a function of proportional, integral and differential value is
calculated based on the deviation input, for outputting the calculation result controlled to achieve
regulation.
Incremental PID control algorithm
∆u n = u n − u(n − 1)
∆u n = �
�
∗ � � − � � − 1 + �
�
∗ � � + �
�
∗ [� � − 2 ∗ � � − 1 + � � − 2 ]
or
∆u n = �
���
+ �
���
+ �
���
among them:
Kp: proportional coefficient, the ratio of the field practice of using Kp = 100;
Ki: integral coefficient;
�
�
= �
�
∗ �/�
�
Kd: differential coefficient;
�
�
= �
�
∗ �
�
/�
Pval: the ratio of action;
�
���
= �
�
∗ � � − � � − 1
Ival: integral role;
�
���
= �
�
∗ � �
Dval: differential effects;
�
���
= �
�
∗ [� � − 2 ∗ � � − 1 + � � − 2 ]
Wherein U (n-1) is the actual control of the amount of time n-1,
△
u (n) to control the
amount of incremental time n, e (n), e (n-1) and e (n-2 ) are n, n-1 and n-2 time amount of the
offset control and the actual value, Ti, Td, and T is the integral time, and derivative time sampling
period (CycleTime), wherein the predetermined deviation as follows: setpoint deviation =
-Measurements.

Output parameters
name Features type of data Output range
Output (output) After the PID
output
REAL Float