Parker 590+ series, Product Manual

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D-64
Programming
DC590+ Series DC Digital Drive
FLD WEAK VARS : MMI Sub-Menu
In certain applications of a DC motor controller, high speeds can only be achieved by reducing the field current and therefore the resultant torque. This
is termed as the Constant-Horsepower region or Field-Weakening region, and the speed at which it begins is known as the Base Speed.
FIELD CONTROL
Parameter Tag Range
FIELD ENABLE 170 DISABLED / ENABLED
Enables and disables the drive motor Field Control.
SETPOINT 171 0.00 to 100.00 %
Field current setpoint as percentage of calibrated value.
PROP. GAIN 173 0.00 to 100.00
This is the proportional gain adjustment of the field current PI loop. The default of 0.10 is equivalent to a real gain of 10.
INT. GAIN 172 0.00 to 100.00
This is the integral gain adjustment of the field current PI loop.
FLD. WEAK ENABLE 174 DISABLED/STANDARD/ADVANCED
Activates the additional motor back-emf, gain-limited PI loop for field weakening (field spillover) control.
STANDARD mode uses the control loop to convert the back-emf in excess of the MAX VOLTS setting, into a reduction of the demanded field
current.
ADVANCED mode also adds in a feedforward control term, based on a comparison of the speed feedback to the calculated base speed,
and uses adaptive gain, in both the back-emf and speed control loops, to compensate for the gain effects of reduced field operation.
EMF LEAD 175 0.10 to 50.00
With field weakening control enabled, a gain-limited PI loop is brought into operation. This is the lead time constant adjustment of the field
weakening PI loop. With a default of 2.00, real time constant = 200ms.
Refer to Chapter 5: "Control Loops" for details of Tuning.
EMF LAG 176 0.00 to 200.00
This is the lag time constant adjustment of the field weakening PI loop
With a default of 40.00, real time constant = 4000ms.
Refer to Chapter 5: "Control Loops" for details of Tuning.
EMF GAIN 177 0.00 to 100.00
This is the steady-state gain adjustment of the field weakening PI loop.
With a default of 0.30, real gain = 30.
Refer to Chapter 5: "Control Loops" for details of Tuning.