Omron SYSDRIVE MX2 SERIES, Руководство пользователя

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6 Vector Control and Applied Functions
6 - 10 Multi-function Compact Inverter 3G3MX2-V1 User’s Manual (I585-E1)
• To use sensorless vector control method, perform offline auto-tuning.
If you cannot perform offline auto-tuning, set motor parameters appropriately according to 6-1-3
Motor Parameter Settings on page 6-9.
• The inverter may not provide sufficient performance characteristics if your motor is two or more sizes
smaller than the maximum applicable motor capacity. This is because the inverter requires a current
accuracy of at least 50% of the rated current.
• If the sensorless vector control method does not provide the intended performance characteristics,
adjust the appropriate motor parameter depending on the phenomenon, as shown in the following table.
Precautions for Correct Use
• Before adjusting the 1st/2nd Speed Response (H005/H205), calculate the motor-shaft con-
version of the moment of load inertia, add the moment of inertia of the motor to it, and set the
sum in the 1st/2nd Motor Parameter J (H024/H224/H034/H234).
For 1st/2nd Speed Response (H005/H205), the larger the set value, the higher the response
speed, which results in a steep torque rise; the smaller the set value, the lower the response
speed, which results in gradual torque rise.
• If you use a motor one size lower than the maximum applicable motor capacity for the
inverter, to prevent motor burnout, set the Torque Limit 1 to 4 (b041 to b044) to limit values
less than the value calculated from the following formula, then enable the torque limit func-
tion. For details on the torque limit function, refer to
6-2-1 Torque Limit Function Settings on
page 6-12.
Torque Limit set value (max.) = 200%
×
[Rated motor current] / [Rated output current of inverter]
6-1-4 Adjustments for Sensorless Vector Control
Operation
status
Phenomenon Adjustment method
Adjustment
item
Power
running
Actual motor speed is
lower than target speed. Increase the Motor Parameter R2 value gradually,
up to 120% of the set value. H021/H221/H031/
H231
Actual motor speed is
higher than target speed. Decrease the Motor Parameter R2 value gradually,
up to 80% of the set value. H021/H221/H031/
H231
Regeneration
Torque is insufficient at low
frequencies (a few Hz).
Increase the Motor Parameter R1 value gradually,
up to 120% of the set value. H020/H220/H030/
H230
Increase the Motor Parameter Io value gradually,
up to 120% of the set value. H023/H223/H033/
H233
During
startup
Shock occurs during
startup.
Decrease the Speed Response value. H005/H205
Decrease the Motor Parameter J value gradually,
relative to the set value. H024/H224/
H034/H234
Motor rotates momentarily
in opposite direction to
specified rotation direction. Set the Reverse Rotation Prevention Selection
(b046) to 01 (Enabled). b046
During
deceleration
Motor is hunting.
Decrease the Speed Response value. H005/H205
Decrease the Motor Parameter J value gradually,
relative to the set value. H024/H224/
H034/H234
During torque
limit
Torque becomes insuffi-
cient at low frequencies
when torque limit is
enabled. Decrease the torque limit. b021/b221/
b040 to b044
Low-frequency
operation
Rotation is unstable.
Increase the Speed Response value. H005/H205
Increase the Motor Parameter J value gradually,
relative to the set value. H024/H224/
H034/H234
(Example) If the Inverter capacity and the motor capacity are 0.75 kW (rated output current =
5.0 A) and 0.4 kW (rated current = 2.3 A), respectively, set the torque limit values
below the following:
Torque Limit set value (max.) = 200%
×
(2.3 A) / (5.0 A) = 92%