Illustration 3.4 Control Structure in Flux Sensorless Open Loop and Closed Loop Configurations
See the chapter Active/Inactive Parameters in Different Drive Control Modes in the Programming Guide for an overview of
which control configuration is available, depending on selection of AC motor or PM Non salient motor. In the shown config-
uration, 1-01 Motor Control Principle is set to [2] Flux sensorless and 1-00 Configuration Mode is set to [0] Speed open loop. The
resulting reference from the reference handling system is fed through the ramp and speed limitations as determined by the
parameter settings indicated.
An estimated speed feedback is generated to the Speed PID to control the output frequency.
The Speed PID must be set with its P,I, and D parameters (parameter group 7-0* Speed PID control).
Select [3] Process in 1-00 Configuration Mode to use the process PID control for closed loop control of i.e. speed or pressure
in the controlled application. The Process PID parameters are found in parameter group 7-2* Process Ctrl. Feedb and 7-3*
Process PID Ctrl.
Introduction
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