6.2 Motor Performance Fine-TuningThis section offers helpful information for counteracting oscillation, hunting, and other problems that occur while performinga trial run. Refer to the section below that corresponds to the motor control method used.Note: This section describes commonly edited parameters that may be set incorrectly. Consult Yaskawa for more information on detailed settingsand for fine-tuning the drive.u Fine-Tuning V/f ControlTable 6.1 Parameters for Fine-Tuning Performance in V/fProblem Parameter No. Corrective Action Default SuggestedSettingMotor hunting andoscillation at speedsbetween 10 and 40 HzHunting Prevention Gain(n1-02)• Reduce the setting if insufficient motor torque relative to the sizeof the load causes hunting.• Increase the setting when motor hunting and oscillation occurwith a light load.• Reduce the setting if hunting occurs when using a motor with arelatively low inductance, such as a high-frequency motor or amotor with a larger frame size.1.00 0.10 to 2.00• Motor noise• Motor hunting andoscillation at speeds upto 40 HzCarrier FrequencySelection (C6-02)• Increase the carrier frequency If the motor noise is too loud.• Lower the carrier frequency when motor hunting and oscillationoccur at speeds up to 40 Hz.• The default setting for the carrier frequency depends on the drivecapacity (o2-04).1 (2 kHz) 1 to max. setting• Poor torque or speedresponse• Motor hunting andoscillationTorque CompensationPrimary Delay Time(C4-02)• Reduce the setting if motor torque and speed response are tooslow.• Increase the setting if motor hunting and oscillation occur.Depends ono2-04, DriveModelSelection100 to 1000 ms• Poor motor torque atspeeds below 10 Hz• Motor hunting andoscillationTorque CompensationGain (C4-01)• Increase the setting if motor torque is insufficient at speedsbelow 10 Hz.• Reduce the setting if motor hunting and oscillation with arelatively light load.1.00 0.50 to 1.50• Poor motor torque atlow speeds• Motor instability atmotor startV/f Pattern Selection(E1-03)• Increase the setting if motor torque is insufficient at speedsbelow 10 Hz.• Reduce the setting If motor instability occurs at motor start.• Set E1-03 to a pattern that fits the application.Depends ono2-04 Default setting±5 Vu Parameters to Minimize Motor Hunting and OscillationIn addition to the parameters discussed in Table 6.1, parameters in Table 6.2 indirectly affect motor hunting and oscillation.Table 6.2 Parameters that Affect Control Performance in ApplicationsName(Parameter No.) ApplicationAccel/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 and C2-02) 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 when the load is too heavy or during sudden acceleration/deceleration.• Adjustment is not normally necessary because Stall Prevention is enabled as a default.6.2 Motor Performance Fine-Tuning224 YASKAWA ELECTRIC SIEP YAIZ1B 01E YASKAWA AC Drive – Z1000 Bypass Technical Manual
