Mitsubishi Electric FR-A820-04750-GF Instruction Manual page 113

 Tuning adjustment (Pr.1002)
• The overcurrent protective function may be activated during Lq tuning for an easily magnetically saturated motor
(motor with a large Lq decay ratio). In such case, adjust the target flowing current used for tuning with Pr.1002
Lq tuning target current adjustment coefficient.
 Changing the motor constants
• The motor constants can be set directly when the motor constants are known in advance, or by using the data
measured during offline auto tuning.
• According to the Pr.71 (Pr.450) setting, the range of the motor constant parameter setting values and units can
be changed. The changed settings are stored in the EEPROM as the motor constant parameters.
 Changing the motor constants (when setting motor constants in
units of Ω, mH, or A)
• Set Pr.71 as follows.
PM motor
• Set desired values as the motor constant parameters.
First Second
motor Pr. motor Pr.
90 458
92 460
93 461
706 738
859 860
1412 1413
NOTE
• If "9999" is set, tuning data will be invalid. When the EM-A motor is selected, the EM-A constant is used.
• To change a motor induced voltage constant of PM motors, the setting in Pr.706 Induced voltage constant (phi
f) or Pr.738 Second motor induced voltage constant (phi f) must be changed. If the constant after the change
exceeds the setting range of Pr.706 or Pr.738 (0 to 5000 mV (rad/s)), set Pr.1412 Motor induced voltage constant
(phi f) exponent or Pr.1413 Second motor induced voltage constant (phi f) exponent. Set a value in the
exponent n in the formula, Pr.706 (Pr.738) × 10
• When Pr.1412 (Pr.1413) = "9999", the motor induced voltage constant is as set in Pr.706 (Pr.738). (No exponent
setting)
Motor
EM-A
Name
Motor constant (R1)
Motor constant (L1)/d-axis inductance (Ld)
Motor constant (L2)/q-axis inductance (Lq)
Induced voltage constant (phi f)
Torque current/Rated PM motor current
Motor induced voltage constant (phi f)
exponent
1140
Setting range
0 to 50 Ω, 9999
0 to 500 mH, 9999
0 to 500 mH, 9999
0 to 5000 mV (rad/s), 9999 0.1 mV (rad/s)
0 to 500 A, 9999
0 to 2, 9999
n
[mV (rad/s)], to set the induced voltage constant (phi f).
6
Pr.71 setting
Setting
increments
0.001 Ω
0.01 mH
0.01 mH
0.01 A
1
BCN-C22005-1008
Initial
value
9999