Mitsubishi Electric FR-A800, Instruction Manual

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Parameters Speed control under Real sensorless vector control, vector control, PM sensorless vector control
FR-A800 5 - 97
5.3.5 Performing high-accuracy, fast-response control (gain adjustment for Real
sensorless vector control, vector control and PM sensorless vector control)
The load inertia ratio (load moment of inertia) for the motor is calculated in real time from the torque
command and rotation speed during motor driving by the vector control. Because the optimum gain
for speed control and position control is set automatically from the load inertia ratio and the response
level, the work required for gain adjustment is reduced. (Easy gain tuning)
If the load inertia ratio cannot be calculated due to load fluctuations, or under Real sensorless vector
control or PM sensorless vector control, the control gain can be set automatically by entering the load
inertia ratio manually.
Manual gain adjustment is useful for achieving optimum machine performance or improving unfa-
vorable conditions, such as vibration and acoustic noise during operation with high load inertia or
gear backlash.
The value for the FR-A820-03160(55K) or lower and FR-A840-01800(55K) or lower.
The value for the FR-A820-03800(75K) or higher and FR-A840-02160(75K) or higher.
Pr. Name
Initial
value
Setting
range
Description
818
C112
Easy gain tuning response
level setting
2 1 to 15
Set the response level.
1 (slow-response) to 15 (fast-response)
819
C113
Easy gain tuning selection 0
0 No easy gain tuning
1
Gain is calculated with load calculation
(This function is valid under vector control.)
2 Gain is calculated with load (Pr. 880) manual input
820
G211
Speed control P gain 1 60% 0 to 1000%
The proportional gain during speed control is set.
(Setting this parameter higher improves the
trackability for speed command changes. It also
reduces the speed fluctuation caused by external
disturbance.)
821
G212
Speed control integral
time 1
0.333 s 0 to 20 s
The integral time during speed control is set. (Setting
this parameter lower shortens the return time to the
original speed when the speed fluctuates due to
external disturbance.)
830
G311
Speed control P gain 2 9999
0 to 1000%
Second function of Pr. 820 (valid when RT signal is
ON)
9999 The Pr. 820 setting is applied to the operation.
831
G312
Speed control integral
time 2
9999
0 to 20 s
Second function of Pr. 821 (valid when RT signal is
ON)
9999 The Pr. 821 setting is applied to the operation.
880
C114
Load inertia ratio 7-fold 0 to 200-fold Set the load inertia ratio for the motor.
1115
G218
Speed control integral
term clear time
0 ms 0 to 9998 ms
Set time until the integral term is reduced and cleared
after P control switching.
1116
G206
Constant output range
speed control P gain
compensation
0% 0 to 100%
Set a compensation amount of the speed control P
gain in the constant output range (rated speed or
higher).
1117
G261
Speed control P gain 1
(per-unit system)
9999
0 to 300
Set a proportional gain under speed control in the
per-unit system.
9999 The Pr. 820 setting is applied to the operation.
1118
G361
Speed control P gain 2
(per-unit system)
9999
0 to 300 Second function of Pr. 1117 (valid when RT signal ON)
9999 The Pr. 1117 setting is applied to the operation.
1121
G260
Per-unit speed control
reference frequency
120 Hz
0 to 400 Hz
Set the speed at 100% when setting speed control P
gain or model speed control gain in the per-unit
system.
60 Hz
Sensorless Sensorless Sensorless Vector Vector Vector PM PM PM