32
The parameters A5.00
～
A5.07 are only valid for vector
control mode.
Under vector control mode,it can change the speed
response character of vector control through adjusting
the proportional gain P and integral time I for speed
regulator.
1.The structure of speed regulator (ASR) is shown in
Fig.6-15.In the figure, K
P
is proportional gain P. T
I
is
integral time I.
Fig.6-15 Speed regulator
When integral time is set to 0 (A5.02
＝
0
，
A5.05
＝
0),then the integral is invalid and the speed loop is just a
proportional regulator.
2
．
Tuning of proportional gain P and integral time I for
speed regulator(ASR).
Fig.6-16 The relationship between step response and PI
parameters of speed regulator(ASR)
When increasing proportional gain P,it can speed up the
system’s dynamic response.But if P is too big,the system
will become oscillating.
When decreasing integral time I,it can speed up the
system’s dynamic response.But if I is too small,the
sysem will become overshoot and easily oscillating.
Generally, to adjust proportional gain P firstly.The value
of P can be increased as big as possible if the system
don’t become oscillating.Then adjust integral time to
make the system with fast response but small
overshoot.The speed step response curve of speed,when
set a better value to P and I parameters,is shown in
Fig.6-17.(The speed response curve can be observed by
analog output terminal AO1,please refer to Group A6)
Fig.6-17 The step response with better dynamic
performance
Note:
If the PI parameters are set incorrectly,it will cause
over-voltage fault when the system is accelerated to high
speed quickly(If the system doesn’t connect external
braking resistor or braking unit),that is because the
energy return under the system’s regenerative braking
when the system is dropping after speed overshoot.It can
be avoided by adjusting PI parameters
3
．
The PI parameters’ adjustment for speed
regulator(ASR) in the high/low speed running occasion
To set the switching frequency of ASR (A5.07) if the
system requires fast response in high and low speed
running with load.Generally when the system is running
at a low frequency,user can increase proportional gain P
and decrease integral time I if user wants to enhance the
dynamic response.The sequence for adjusting the
parameters of speed regulator is as following:
1
）
Select a suitable switching frequency( A5.07).
2
）
Adjust the proportional gain (A5.01) and integral
time(A5.02) when running at high speed,ensure the
Speed
Command
Speed
command
Proportional gain
is bigger
Proportional gain
is smaller
Speed
command
Integral time is smaller
Integral time is bigger
(a)
(b)
A6.10, A6.11
