Parker AC890PX Series, Engineering Reference

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D-144
A p p e n d i x D : P r o g r a m m i n g
AC890PX AC Drive
SPEED LOOP
SETUP::MOTOR CONTROL::SPEED LOOP
Designed for SENSORLESS VEC and CLOSED-LOOP VEC Motor Control Modes.
This function block controls the speed of the motor by comparing the actual speed to the demanded speed, and applying more or less torque in
response to the error.
Fixed Inputs and Outputs
These parameters are not viewable on the keypad, They are accessible using the DSE 890 Configuration Tool.
Speed Demand
This is connected to the output of the REFERENCE function block.
Speed Feedback
The speed feedback is derived from the encoder when the Control Mode is configured as CLOSED-LOOP VEC. When configured as
SENSORLESS VEC the speed feedback is calculated from the voltages and currents slowing in the motor, and the motor model.
Torque Demand
The output of the SPEED LOOP function block is a torque demand. This torque demand is passed on to the TORQUE LIMIT function block.
Parameter Descriptions
SPEED PROP GAIN PREF: 78.01 Default: 20.0 Range: 0.0 to 3000.0
Sets the proportional gain of the loop.
Speed error (revolutions per second) x proportional gain = torque percent.
SPEED INT TIME PREF: 78.02 Default: 100 ms Range: 1 to 15000 ms
This is the integral time constant of the speed loop. A speed error which causes the proportional term to produce a torque demand T, will cause the
integral term to also ramp up to a torque demand T after a time equal to “speed int time”.
INT DEFEAT
PREF: 78.03 Default: FALSE Range: FALSE / TRUE
When TRUE, the integral term does not operate.
SPEED INT PRESET PREF: 78.04 Default: 0.00 % Range: -500.00 to 500.00 %
The integral term will be preset to this value when the drive starts.