SSD 605C, Product Manual

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6-28
Programming Your Application
605C Frequency Inverter
FLUXING
This function block allows user
parameterisation of the conventional
(volts/hertz) fluxing strategy of the
Inverter. This is achieved though two
flexible volts to frequency templates.
Starting torque performance can also be
tailored through the FIXED BOOST and
AUTO BOOST parameters.
MMI Menu Map
1 SETUP PARAMETERS
2 FUNCTION BLOCKS
3 MOTOR CONTROL
4 FLUXING
V/F SHAPE
V/F SCALE
BASE FREQUENCY
LIMIT FREQUENCY
FIXED BOOST
AUTO BOOST
FLUXING
LINEAR LAW – [104] V/F SHAPE –
100.00 % – [105] V/F SCALE –
* 50.0 Hz – [106] BASE FREQUENCY –
120 Hz – [113] LIMIT FREQUENCY –
0.00 % – [107] FIXED BOOST –
0.00 % – [108] AUTO BOOST –
Parameter Descriptions
V/F SHAPE Range: Enumerated - see below
This parameter determines the type of volts to frequency template is used to flux the motor. The
choices of this parameter are:
Enumerated Value : V/F Shape
0 : LINEAR LAW
1 : FAN LAW
V/F SCALE Range: 0.00 to 100.00 %
This parameter directly scales the voltage output of the volts to frequency template. This scaling
takes place before any boost or auto boost is added.
BASE FREQUENCY Range: 7.5 to 480.0 Hz
This parameter determines the frequency at which maximum output volts is generated. Below
base frequency, the volts will vary with frequency as determined by the V/F SHAPE parameter.
Above base frequency, the volts will saturate at the maximum value.
Setting the BASE FREQUENCY parameter to a value greater than LIMIT FREQUENCY
parameter, results in the internal value of base frequency used for the volts to frequency
template being clamped at the set value of limit frequency.
LIMIT FREQUENCY Range: Enumerated - see below
Sets the value of the maximum output frequency the Inverter is able to supply to the motor. The
choices of this parameter are:
Enumerated Value : Limit Frequency
0 : 120 Hz
1 : 240 Hz
2 : 480 Hz
FIXED BOOST Range: 0.00 to 25.00 %
This parameter allows for no-load stator resistance voltage drop compensation. This correctly
fluxes the motor (under no-load conditions) at low output frequencies, thereby increasing
available motor torque. Fixed boost can be set in addition to auto boost.
AUTO BOOST Range: 0.00 to 25.00 %
This parameter allows for load dependent stator resistance voltage drop compensation. This
correctly fluxes the motor (under load conditions) at low output frequencies, thereby increasing
available motor torque. Auto boost can be set in addition to fixed boost.
The value of the AUTO BOOST parameter determines level of additional volts supplied to the
motor for 100% load.
Setting the value of auto boost too high can cause the Inverter to enter current limit. If this
occurs, the Inverter will be unable to ramp up in speed. Reducing the value of auto boost will
eliminate this problem.