V/f Control and Closed Loop V/f Control

Hunting or oscillation in the middle speed range (10 Hz to 40 Hz)

n1-02 [Hunting Prevention Gain Setting]

• If torque is not sufficient with heavy loads, decrease the setting value.

• If hunting or oscillation occur with light loads, increase the setting value.

• If hunting occurs with a low-inductance motor, for example a motor with a larger frame size or a high-frequency motor, lower the setting value.

1.00

0.10 - 2.00

• The volume of the motor excitation sound is too high.

• Hunting or oscillation in the low speed range (10 Hz or lower), or in the middle speed range (10 Hz to 40 Hz)

C6-02 [Carrier Frequency Selection]

• If the volume of the motor excitation sound is too high, increase the carrier frequency.

• If hunting or oscillation occur in the low or middle speed range, decrease the carrier frequency.

1 (2 kHz) ¹

1 to upper limit value

• Unsatisfactory motor torque and speed response

• Hunting or oscillation

C4-02 [Torque Compensation Delay Time]

• If torque or speed response are slow, decrease the setting value.

• If hunting or oscillation occur, increase the setting value.

200 ms ²

100 ms to 1000 ms

• Torque in the low speed range (10 Hz or slower) is not sufficient.

• Hunting or oscillation

C4-01 [Torque Compensation Gain]

• If torque is not sufficient in the low speed range (10 Hz or slower), increase the setting value.

• If hunting or oscillation occur with light loads, decrease the setting value.

1.00

0.50 - 1.50

• Torque in the low speed range (10 Hz or slower) is not sufficient.

• Large initial vibration at start up.

• E1-08 [Mid Point A Voltage]

• E1-10 [Minimum Output Voltage]

• If torque is not sufficient in the low speed range (10 Hz or slower), increase the setting value.

• If there is large initial vibration at start up, decrease the setting value

• E1-08: 15.0 V ³

• E1-10: 9.0 V ³

Default setting +/- 5 V ⁴

In V/f control method, speed precision is unsatisfactory.

C3-01 [Slip Compensation Gain]

Set E2-01 [Motor Rated Current], E2-02 [Motor Rated Slip], and E2-03 [Motor No-Load Current], then adjust C3-01.

0.0 (no slip compensation)

0.5 - 1.5

In Closed Loop V/f control method, speed precision is unsatisfactory.

• C5-01 [ASR Proportional Gain 1]

• C5-02 [ASR Integral Time 1] ⁵

Adjust C5-01, C5-02.

• C5-01: 0.20

• C5-02: 0.200 s

• Proportional gain = 0.10 to 1.00

• Integral time = 0.100 to 2.000 s