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Speed loop gain
Because the response of the speed loop is low, it will become the delay factor of the outer position loop,
so overshoot or vibration of the speed command will occur. Therefore, in the range of no vibration of
mechanical system, the larger the setting value, the more stable the servo system and the better the
responsiveness.
Integral time constant of speed loop
In order to respond to small inputs, the speed loop contains integral elements. Because this integral
factor is a delay factor for servo system, when the time constant is too large, it will overshoot or
prolong the positioning time, which will make the response worse.
The relationship between the gain of the speed loop and the integral time constant of the speed loop is
approximately as follows:
P1-00 × P1-01 = 636620
integral time
constant of speed
loop
Position loop gain
When the model loop is invalid (P2-47.0=0), the responsiveness of the position loop of the servo unit is
determined by the gain of the position loop. The higher the position loop gain is, the higher the
responsiveness is and the shorter the positioning time is. Generally speaking, the gain of position loop
cannot be increased beyond the natural vibration number of mechanical system. Therefore, in order to
set the position loop gain to a larger value, it is necessary to improve the rigidity of the machine and
increase the number of inherent vibration of the machine.
Filter time constant of torque instruction
When machine vibration may be caused by servo drive, it is possible to eliminate vibration by adjusting
the filtering time parameters of the following torque instructions. The smaller the numerical value, the
better the response control can be, but it is restricted by the machine conditions. When vibration occurs,
the parameter is generally reduced, and the adjustment range is suggested to be 10-150.
Filter time constant of
torque instruction 1
Model loop gain
When the model loop is valid (P2-47.0=1), the response of the servo system is determined by the gain
of the model loop. If the gain of the model loop is increased, the responsiveness is increased and the
positioning time is shortened. At this time, the response of the servo system depends on this parameter,
not P1-02 (position loop gain). The gain of the model loop is only valid in position mode.