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 appropriate control method in this section.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/f ControlProblem Parameter No. Corrective Action Default SuggestedSettingMotor hunting andoscillation at speedsbetween 10 and 40 HzHunting PreventionGain (n1-02)• Reduce the setting if insufficient motor torque relative to thesize of 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 witha relatively low inductance, such as a high-frequency motor ora motor with a larger frame size.1.00 0.10 to 2.00• Motor noise• Motor hunting andoscillation at speedsup to 40 HzCarrier FrequencySelection (C6-02)• Increase the carrier frequency If the motor noise is too loud.• Lower the carrier frequency when motor hunting andoscillation occur at speeds up to 40 Hz.• The default setting for the carrier frequency depends on thedrive capacity (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.200 ms 100 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 startMid Output Voltage A(E1-08)Minimum OutputVoltage (E1-10)• Increase the setting if motor torque is insufficient at speedsbelow 10 Hz.• Reduce the setting If motor instability occurs at motor start.Depends ono2-04, DriveModelSelectionDefault setting±5 VPoor speed precision(V/f control) Slip Compensation Gain(C3-01)Set the motor-rated current (E2-01), motor-rated slip (E2-02),and motor no-load current (E2-03), then adjust the slipcompensation gain (C3-01).0.0(no slipcompen-sation)0.5 to 1.5u 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.) ApplicationDwell Function(b6-01 through b6-04) Prevents motor speed loss by maintaining the output frequency when working with heavy loads or when thereis powerful backlash on the machine side.Accel/Decel Time(C1-01 through C1-11) Adjusting accel and decel times will affect the torque presented to the motor during acceleration ordeceleration.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 when the load is too heavy or during sudden acceleration/deceleration.• Adjustment is not normally necessary because Stall Prevention is enabled as a default. Set L3-04 to 0 todisable Stall Prevention during deceleration when using a braking resistor.6.2 Motor Performance Fine-Tuning290 YASKAWA SIEP YAIP1U 01C AC Drive - P1000 Technical Manual
