GE AF-650 GP Design And Installation Manual page 56

Application Set-Up Examples
•
Closed loop in Flux mode with encoder feedback
offers superior performance in all 4 quadrants
and at all motor speeds.
•
Open loop in Advanced Vector Control mode. The
function is used in mechanical robust
applications, but the accuracy is limited. Open
loop torque function works basically only in one
speed direction. The torque is calculated on basic
of current measurement internal in the frequency
converter.
Speed/torque reference
The reference to these controls can either be a single
reference or be the sum of various references including
relatively scaled references. The handling of references is
explained in detail in chapter 6.4 References.
The frequency converter is capable of controlling either the
speed or the torque on the motor shaft. Setting
parameter H-40 Configuration Mode determines the type of
control.
Speed control
There are two types of speed control:
•
Speed open loop control which does not require
any feedback from motor (sensorless).
•
Speed closed loop PID control requires a speed
feedback to an input. A properly optimized speed
closed loop control has higher accuracy than a
speed open loop control.
Selects which input to use as speed PID feedback in
parameter PI-00 Speed PID Feedback Source.
Torque control
The torque control function is used in applications where
the torque on motor output shaft is controlling the
application as tension control. Torque control can be
selected in parameter H-40 Configuration Mode, either in
Advanced Vector Control [4] Torque open loop or Flux
control closed loop with motor speed feedback [2]. Torque
setting is done by setting an analog, digital, or bus
controlled reference. When running torque control, it is
recommended to make a full Auto tune procedure as the
correct motor data are of high importance for optimal
performance.
•
Closed loop in Flux mode with encoder feedback
offers superior performance in all four quadrants
and at all motor speeds.
•
Open loop in Advanced Vector Control mode. The
function is used in mechanical robust
applications, but the accuracy is limited. Open
loop torque function works basically only in one
speed direction. The torque is calculated on basic
of current measurement internal in the frequency
converter.
MG35M402
AF-650 GP™ Design and Installation Guide
Speed/torque reference
The reference to these controls can either be a single
reference or be the sum of various references including
relatively scaled references. The handling of references is
explained in detail later in this section.
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