Omron 3G3AX-PG, User Manual

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4-2
4-2 Sensor Vector Control (speed control)
4
Func
tions
4-2 Sensor Vector Control (speed control)
To use this function, set V/f characteristics selection A044 to “05” (V2), and V2 control mode selec-
tion P012 to “00” (speed control).
(“Sensor vector control” can be selected for 1st control only.)
To use this function, make sure that the motor parameter settings are suitable for your motor. For
details, refer to “Chapter 4 Functions, 4-2 Function Mode, Moter Parameter Selection” in the gen-
eral-purpose Inverter 3G3RX User’s Manual.
Also, be sure to set the number of your encoder pulses.
With V2 control mode selection P012, you can select four types of control modes: Speed control,
Pulse train position control, Absolute position control, and High-resolution absolute position control.
Note the following before use:
• Sufficient characteristics may not be obtained if you select a motor size two or more ranks lower
than the motor size specified.
• If the Inverter does not normally accelerate, or if overload protection is activated, check the phase
sequence of the encoder signal. (If phase A is advanced by 90 ° from phase B during forward
run, it is judged as being normal.)
When running the Inverter with V/f characteristics selection A044 set to “00” (VC), you can
check the rotation direction with real frequency monitor d008.
(If positive frequency is detected when the forward command is activated, or if negative fre-
quency is detected when the reverse command is activated, the rotation direction is judged as
being normal.)
If sensor vector control cannot provide the desired characteristics, adjust the motor parameters de-
pending on the phenomenon, as shown in the table below.
Note 1: Make sure that the carrier frequency (b083) is not lower than 2.1 kHz. If the carrier frequency is at 2.1 kHz or
lower, the Inverter will not operate normally.
Note 2: To use a motor with a capacity lower than that of the Inverter, set a torque limit value (b041 to b044), while
keeping the value
α
in the following formula at 200% or lower.
Otherwise, the motor may burn out.
α
= Torque limit set value
×
(Inverter capacity) / (Motor capacity)
(Example) If the Inverter capacity is 0.75 kW and the motor capacity is 0.4 kW, the torque limit set value for
α
=
200%, calculated with the above formula, is as follows:
Torque limit set value (b041 to b044) =
α ×
(Motor capacity) / (Inverter capacity)
= 200%
×
(0.4 kW) / (0.75 kW) = 106%
Operation
status
Phenomenon Adjustment method Adjustment item
During
startup Shock occurs during
startup.
Reduce motor parameter J from the set parameter. H024/H034
During
deceleration
Motor hunting occurs.
Reduce the speed response. H005
Reduce motor parameter J from the set parameter. H024/H034
During torque
limit
Insufficient torque at low
frequency during torque
limit
Set an overload limit level lower than the torque limit
level. b021
b041 to b044
Low-frequen-
cy operation
Rotation is not constant. Increase motor parameter J from the set parameter. H024/H034
Related functions
A001, A044, F001, b040 , H002, H003, H004 , H020 , H021 , H022 , H023 ,
H050 , H051 , H052 , P011, P012