7. EXPLANATION OF PARAMETERS
7－20
7.1.9.2 Offline automatic tuning function
● Outline of offline automatic tuning function
The offline automatic tuning function operates the motor through the remote operator and estimates load
inertia from its operating status. With this, proper parameters are automatically set. Four parameters
for position loop gain (Kp), velocity loop proportional gain (Kvp), velocity loop integral time constant (Tvi)
and current command LPF (ILPF) are set using this function.
● Precautions on working and load conditions
If the servo vibrates before tuning when turned on, reduce the proportional gain Kvp and increase the
integral time constant Tvi beforehand. When offline automatic tuning is executed, forward/backward
revolution is performed. Accordingly, secure one turn or more for both forward and backward
revolution as the motor operating range. Use this function only when safety is secured even under
vibrating conditions and no damage to the machine occurs. In the following cases, proper parameters
may not be set by the offline automatic tuning function or a tuning error may occur ("Tn_G Error" is
displayed).
• The load inertia is significantly larger than that allowed.
• The variation in load inertia or torque is large.
• The backlash of ball screws and gears is large.
• The machine rigidity including couplings is low, causing machine resonance.
• While offline automatic tuning function is executed, the remote operator is dismounted from the
Amplifier main body (remote operator POWER OFF).
• While offline automatic tuning function is executed, main circuit power supply is cut off or an alarm occurs
• When the output current is limited by current limit permit input.
• The sequence current limit value (page 12 of Mode 1) is set to 100% or low.
• The gain switching through external input is enabled and the changeover input signal is ON (during
gain switching).
• The slide switch on the front of the amplifier is set to GAIN and the rotary switch is set to other than 0.
• Over travel status
• While command input is inhibited by holding brake timing or others.
● Offline automatic tuning operation
• For tuning rigidity to be tuned, select Low, Middle or High according to machine rigidity.
• When offline automatic tuning is executed, forward/backward revolution is performed for about 0.5
seconds with a torque command (equivalent to the rated torque at the peak) of about 60 Hz sine
waveform. For the motor operating range at this time, secure one turn or more as standard, though
this varies depending on the load conditions.
• When offline automatic tuning is ended normally, proper parameters are automatically set from the
estimated load inertia and the parameters are stored in the non-volatile memory.
• After execution of this automatic tuning function, a deviation of the position loop may be left.
For this reason, be sure to clear the deviation before returning to normal operation.
● Setting together with Real time automatic tuning
In case of devise making real time automatic tuning valid during normal operation, it is required to set
the gain in initial operation to low. Therefore, when executing offline automatic tuning in the device
making real time automatic tuning valid, selecting low for machine rigidity is recommended.
(Refer to Chapter 11 for Tunings)
To Next Page
Loading...
