E6581301

Examples of setting the motor constants

a)Combination with a Toshiba standard motor (4P motor with the same capacity as the inverter)

Inverter : VFAS1-2037PL

Motor : 3.7kW-4P-60Hz

1)Set the V/f control mode selection ￿￿ at ￿ (Sensorless vector control).

2)Set the auto-tuning 1 (￿￿￿￿) at ￿. (When the cable length is 30m or over.)

b)Combination with a standard motor other than the above Toshiba motor

Inverter : VFAS1-2037PL

Motor : 2.2kW-2P-50Hz

1)Set the V/f control mode selection ￿￿ at ￿ (Sensorless vector control).

2)Set ￿￿, ￿￿￿, ￿￿￿￿, ￿￿￿￿ and ￿￿￿￿, as specified on the motor nameplate.

3)Set the auto-tuning 1(￿￿￿￿) at ￿.

4)Set the auto-tuning 1 (￿￿￿￿) at ￿.

(2)Setting sensorless vector control and manual independently Setting motor constants

Perform all operations in the flowchart on the previous page. If the motor specifications are unknown, enter only the motor capacity (￿￿￿￿) and set parameter ￿￿￿￿ to ￿. After that, run the motor and set other parameters with the following explanation about parameter adjustments as a guide.

Setting motor parameters are necessary when Pt is set at 2, 3, 4, 7 or 8.

(1) Slip frequency gain ￿￿￿￿

6

This parameter is to adjust the slippage of the motor.

Setting this parameter at a larger number can reduce the slippage of the motor. However, setting it at an excessively large number may result in hunting, etc., and thus cause an unstable operation.

(2)Motor constant 1 ￿￿￿￿ (Torque boost) (Motor test reports may be useful.)

This parameter is to adjust the primary resistance of the motor. Setting this parameter at a larger value can prevent the drop of the motor torque in low speed ranges due to a voltage drop. However, setting it at an excessively large number may result in large current in low speed range and appearance of an overload trip, etc.

(3)Motor constant 2 ￿￿￿￿ (No-load current) (Motor test reports may be useful.)

This parameter is to adjust the exciting inductance of the motor. The larger the set value, the more exciting current can be increased. Note that specifying a too large value for the motor constant may cause hunting.

(4)Motor constant 3 ￿￿￿￿ (Leak inductance) (Motor test reports may be useful.)

This parameter is to adjust the leakage inductance of the motor. The larger the set value, the larger torque the motor can produce in high-speed ranges.

(5)Motor constant 4 ￿￿￿￿ (Rated slip)

This parameter is to adjust the secondary resistance of the motor. The amount of compensation for slip increases with increase in this value.

(6)￿￿￿￿ (Speed loop proportional gain)!

This parameter is to adjust the gain responsive to speed. Specifying a large gain increases the speed of response, but specifying an excessively large gain may result in the occurrence of hunting. If operation is unstable and hunting occurs, operation can be stabilized in most cases by reducing the gain.

(7)￿￿￿￿ (Moment of inertia of load)

This parameter is used to adjust the excess response speed. Specifying a large value reduces the amount of overshoot at the completion of acceleration. So, specify a value appropriate to the actual moment of inertia of the load.

F-41

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Toshiba VF-AS1 instruction manual Examples of setting the motor constants