◆ Parameters to Minimize Motor Hunting and Oscillation
In addition to the parameters discussed on page 296 through 298, the following parameters indirectly affect motor
hunting and oscillation.
Table 6.7 Parameters that Affect Control Performance in Applications
Name (Parameter No.) Application
Dwell Function (b6-01 through b6-04)
Prevents motor speed loss by maintaining the output frequency when working with heavy loads or when there is powerful
backlash on the machine side.
Droop Function (b7-01, b7-02)
Used to balance the load between two motors that drive the same load. Can be used when the control method (A1-02) is set to
3 or 7.
Accel/Decel Time (C1-01 through C1-11) Adjusting accel and decel times will affect the torque presented to the motor during acceleration or deceleration.
S-Curve Characteristics (C2-01 through C2-04) Prevents shock at the beginning and end of acceleration and deceleration.
Jump Frequency (d3-01 through d3-04) Skips over the resonant frequencies of connected machinery.
Analog Filter Time Constant (H3-13) Prevents fluctuation in the analog input signal due to noise.
Stall Prevention (L3-01 through L3-06, L3-11)
• Prevents motor speed loss and overvoltage. Used when the load is too heavy and also during sudden acceleration/
deceleration.
• Adjustment is not normally required because Stall Prevention is enabled as a default. Disable Stall Prevention during
deceleration (L3-04 = “0”) when using a braking resistor.
Torque Limits (L7-01 through L7-04, L7-06, L7-07)
• Sets the maximum torque for Open Loop Vector Control.
• Ensure that the drive capacity is greater than the motor capacity when increasing this setting. Be careful when reducing this
value because motor speed loss may occur with heavy loads.
Feed Forward Control (n5-01 through n5-03)
Used to increase response for acceleration/deceleration or to reduce overshooting when there is low machine rigidity and the
gain of the speed controller (ASR) cannot be increased. The inertia ratio between the load and motor and the acceleration time
of the motor running alone must be set.