Programming Your Application
1-107
690+ Series Frequency Inverter
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
Speed Demand
This is connected to the output of the
SETPOINT SCALE 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 in the motor.
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, which causes the torque to be generated in the motor.
Speed Loop
–
TOTAL SPD DMD RPM [1203]
–
0.00 RPM
–
TOTAL SPD DMD % [1206]
–
0.00 %
–
SPEED ERROR [1207]
–
0.00 %
–
TORQUE DEMAND [1204]
–
0.00 %
–
DIRECT INPUT [1205]
–
0.00 %
–
PHASE INPUT [1397]
–
0.00 %
** 20.00
–
[1187] SPEED PROP GAIN
–
** 100 ms
–
[1188] SPEED INT TIME
–
FALSE
–
[1189] INT DEFEAT
–
0.00 %
–
[1190] SPEED INT PRESET
–
3.0 ms
–
[1191] SPEED DMD FILTER
–
1.5 ms
–
[1192] SPEED FBK FILTER
–
0.00 %
–
[1193] AUX TORQUE DMD
–
5.00 %
–
[1194] ADAPTIVE THRESH
–
20.00
–
[1195] ADAPTIVE P-GAIN
–
NONE
–
[1196] DIRECT IP SELECT
–
1.0000
–
[1197] DIRECT RATIO
–
110.00 %
–
[1198] DIRCT IP POS LIM
–
-110.00 %
–
[1199] DIRCT IP NEG LIM
–
110.00 %
–
[1200] SPEED POS LIM
–
-110.00 %
–
[1201] SPEED NEG LIM
–
FALSE
–
[1202] TORQ DMD ISOLATE
–
MMI Menu Map
1
SETUP
2
MOTOR CONTROL
3
SPEED LOOP
SPEED PROP GAIN
SPEED INT TIME
INT
DEFEAT
SPEED INT PRESET
SPEED DMD FILTER
SPEED FBK FILTER
AUX TORQUE DMD
ADAPTIVE
THRESH
ADAPTIVE
P-GAIN
DIRECT IP SELECT
DIRECT
RATIO
DIRCT IP POS LIM
DIRCT IP NEG LIM
SPEED POS LIM
SPEED NEG LIM
TORQ DMD ISOLATE
TOTAL SPEED RPM
TOTAL SPEED %
SPEED
ERROR
TORQUE
DEMAND
DIRECT
INPUT
PHASE
INPUT
Parameter Descriptions
SPEED PROP GAIN
Range: 0.00 to 300.00
Sets the proportional gain of the loop.
Speed error (revolutions per second) x proportional gain = torque percent.
SPEED INT TIME
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
Range: FALSE / TRUE
When TRUE, the integral term does not operate.
SPEED INT PRESET
Range: -500.00 to 500.00 %
The integral term will be preset to this value when the drive starts.
SPEED DMD FILTER
Range: 0.0 to 14.0 ms
The speed demand is filtered to reduce ripple. The filter is first order with time constant equal
to the value of this parameter.
SPEED FBK FILTER
Range: 0.0 to 15.0 ms
The speed feedback is filtered to reduce ripple, such as that caused by low line count
encoders. The filter is first order with time constant equal to the value of this parameter.
AUX TORQUE DMD
Range: -300.00 to 300.00 %
When the drive is operating in speed control mode, the value of this parameter is added on to
the torque demand produced by the speed loop PI. When the drive is operating in torque
control mode (i.e. “torque demand isolate is TRUE) the speed loop PI does not operate, and
the torque demand becomes the sum of this parameter plus the DIRECT INPUT (if selected).
