YASKAWA Varispeed G7 Series Instruction Manual page 130

Control
Method
Open-loop
vector 2
control
(A1-02 = 4)
(Continued)
* 1. The setting is given for 200 V Class Inverters. Double the voltage for 400 V Class Inverters.
* 2. The adjustment procedure is described in the following section.
* 3. This refers to the frequency near the N4-11 set value when accelerating and the N4-28 set value when decelerating.
* 4. This means that the ratios of E1-10 to E1-09 and E1-08 to E1-07 are close to the ratio of E1-13 to E1-06. If the V/f pattern is too close to a straight line,
the power will be reduced. Do not change the setting more than necessary.
* 5. Adjust the following user constants only when problems occur: b1-10, d5-07, N4-11, N4-28, N4-15, N4-17, N4-29, N4-30, and N4-32 to N4-34.
* 6. This setting is for software versions PRG 1040 and later. The factory setting with software versions PRG 1039 and earlier depends on the Inverter
capacity.
-32
4
Table 4.3 Adjusted User Constants (Continued)
Name (Constant
Performance
Number)
N4-11 (Speed
Countermeasure when
estimator switching
shock is a problem
*5
frequency)
near the speed estima-
N4-28 (Speed
tor switching fre-
estimator switching
quency
*5
frequency 2)
N4-15 (Low-speed
Load tolerance (low-
regeneration stability
speed regenerative
*5
loads)
coefficient 1)
The torque reference
value (U1-09) in the
N4-17 (Torque
low-speed range is
*5
large compared with
adjustment gain)
the medium- and high-
speed ranges.
N4-29 (Torque
Load tolerance (low-
*5
speed electrical loads)
adjustment gain 2)
Controlling hunting
N4-30 (Low-speed
and vibration (low-
regeneration stability
speed regenerative
*5
coefficient 2)
loads)
N4-32 to N4-34
(Speed estimator gain
Controlling hunting
fluctuation frequency
and vibration (6 to 10
1, 2, and fluctuation
Hz)
*5
rate)
Factory
Setting
N4-11:
70 Hz Lower than
N4-28: default value
50 Hz
*3
Default
0.3
value
0.8 0.8 to 1.0
Default
0.10
value
1.0 1.0 to 2.5
N4-32: N4-32:
5 Hz Around 5 Hz
N4-33: N4-33:
20 Hz 20 Hz or less
N4-34: N4-34: 50%
100% to 100%
Recom-
mended Adjustment Method
Setting
Reduce the values of N4-11
and N4-28. (Typically, 5 Hz.)
If the problem is not
improved, use open-loop
vector 1 control (A1-02=2).
Increase the setting if the
power in low-speed regener-
ation is low. (Typically,
increase in intervals of 0.1.)
Increase the setting to 1.0
max. (Typically, increase in
intervals of 0.05.) If the prob-
lem is not improved, bring
the V/f pattern close to a
*4
straight line.
Increase the setting if the
power in low-speed electrical
operation is low. (Typically,
increase in intervals of 0.05.)
Increasing the setting too
much will have the opposite
effect.
If vibration occurs during
low-speed regeneration,
increase the setting until the
speed increase becomes a
problem. (Typically, increase
in intervals of 0.2.)
First accelerate the motor
gradually and set N4-32 to
the lowest speed at which
vibration occurs. Set N4-33
to the highest speed at which
vibration occurs. And then
reduce the setting of N4-34
until the vibration stops.
(Typically, change in inter-
vals of 5%.)