Operating Instructions

Descriptions of Parameter Settings
Descriptions of Parameter Settings
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● When the ratio of the salient pole (Lq / Ld) is lower, increase Pr.10-52 to make the angle detection accurate.
● Pr.10-52 is valid only when Pr.10-53 = 2.
Pr.
Explanation
Settings
Default
10-53
Angle detection method
0: Disabled
1: Force attracting the rotor to zero degrees
2: High frequency injection
3: Pulse injection
0
Set to 2 for IPM; set to 3 for SPM. If these settings cause problems, then set the parameter to 1.
Description Group 11
11 Advanced Parameters
indicates the parameter can be set during operation.
The following abbreviation is used in this parameter group:
● ASR: Adjust Speed Regulator
Pr.
Explanation
Settings
Default
11-00
System control
bit 0: Auto-tuning for ASR and APR
bit 3: Dead time compensation closed
bit 7: Save or do not save the frequency
0
bit 0 = 0: Pr.11-06–Pr.11-11 are valid and Pr.11-03–Pr.11-05 are invalid.
bit 7 = 0: Save the frequency before power is OFF. When power is ON again, the saved frequency is displayed.
bit 7 = 1: Do not save the frequency before power is OFF. When power is ON again, 0.00 Hz is the displayed
frequency.
Pr.
Explanation
Settings
Default
11-01
Per-unit of system inertia
1 to 65535 (256 = 1 PU)
256
To get the system inertia per unit from Pr.11-01, you need to set Pr.11-00 to bit1 = 1 and execute continuous
forward/reverse running.
When Pr.11-01 = 256, it is 1PU. So if you use a 2HP motor, the 2HP motor inertia is 0.00043 kg-cm
2
according to
the table below. If Pr.11-01 = 10000 after tuning, the system inertia is (10000 / 256) x 0.00043 kg-cm
2
.
Perform the operation test with load based on the inertia after tuning. Run the motor in acceleration, deceleration,
and steady speed and observe the values. If values between speed feedback and speed command are close,
steady-state error is small and overshoot is less, then this inertia is a better one.
If the Iq current command from ASR has high-frequency glitch, then decrease the setting. If the response time of
sudden loading is too slow, then increase the setting.
When using torque mode as the control mode, perform the tuning with speed mode first to see if the tuned inertia
can work normally. After verifying with speed mode, change the control mode to torque mode.
The following table shows the base value for the induction motor system inertia (Unit: kg-m^2)