5motor control (mctrl) – Lenze 8400 TopLine User Manual

Page 254

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5

Motor control (MCTRL)

5.9

Servo control (SC)

254

Lenze · 8400 TopLine · Reference manual · DMS 6.0 EN · 06/2014 · TD05/TD14

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Adaptive adaptation of the P component of the field and speed controllers
In the field weakening range, the properties of the drive change due to the reduction of the

magnetisation and the voltage limitation of the inverter. To be able to continue to provide a stable,

well dampened drive behaviour, the servo control has an automatic adaptation of the P component

of the field weakening controller and speed controller.
In the Lenze setting, this function is activated. Depending on the application, this function can be

deactivated via

C00079/2

.

Tip!
Lenze recommends to always activate the adaptation of the field weakening and speed

controller.

Additional limitation of the I component of the speed controller when the voltage limit is reached

(anti-wind-up)
In dynamic acceleration processes in the field weakening range, the acceleration torque is limited

due to the limitation of the maximum output voltage of the inverter. Acceleration ramps that are

set too high (

C00012

) may lead to undesired charging of the integrator of the speed controller,

which result in very strong overshoots of the actual speed value when the setpoint is reached.
The so-called anti-wind-up function serves to intelligently limit the integrator part in dynamic

acceleration processes in the field weakening range so that an overshoot of the actual speed value

can be prevented when the setpoint speed is reached.
This function is deactivated in the Lenze setting because the robustness of the drive may decrease

in the field weakening range. Possible consequences are slight speed variations. If required by the

application, the function can be activated via

C00079/3

.

[5-20] Typical signal characteristics for switched-on/off anti-wind-up function

Parameter

Info

Lenze setting

C00079/2

SC: Adaptive field weakening controller

1: On

Parameter

Info

Lenze setting

C00079/3

SC: n-Ctrl Anti-Wind-Up

0: Off

Anti-wind-up" off (without limitation):

Anti-wind-up" on (with limitation):

Speed setpoint

Actual speed value

t

n [rpm]

Œ



t

n [rpm]

Œ



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