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[2] How to tune each parameter
(2-1) Tuning target of each parameter
There are many parameters, which influence the motor performance in SLV, 0-SLV & V2 control modes.
In some cases auto tuning is not fully sufficient to get the best motor performance because there are
various kinds of motors in the world. It is sometimes necessary to adjust by hand after the auto tuning.
Generally the performance of the motor can be determined from two criteria:
Ø Torque performance at low speed
Ø Speed response against target speed
Table 1 shows main parameters that influence the motor performance inSLV mode. The concept is the same
in 0-SLV and V2 modes as well.
Table 1. Explanation of parameters related to motor performance in SLV mode
Code
H001
Auto tuning mode
Equivalent circuit of one leg of
the motor winding
H002
Motor constant selection
H003
Motor kW
H004
Motor poles
Speed response factor K
H005
H006
Motor stability control factor
H020 / H030
Primary resistance of the
motor R1 [ ]
H021 / H031
Secondary resistance of the
motor R2 [ ]
Torque
Function
R1
L
R2
LM
ideal
Big R2
Small
R2
Speed
This determines the method of auto tuning.
00 (NOR) : Auto tuning invalid
01 (NRT) : Auto tuning with motor at standstill
02 (AUT) : Auto tuning with motor rotation
Auto tuning determines the following motor constants
automatically. (See left figure as well.)
Ÿ R1 (primary resistance)
Ÿ R2 (secondary resistance)
Ÿ L (leakage inductance)
Ÿ I o (magnetizing current at base frequency)
Ÿ J (total load inertia)
Normally better motor performance can be obtained by auto tuning
with motor rotation with an actual load on the motor. But if the
system does not allow rotating the motor, like a lift application for
example, auto tuning with motor at standstill can be used.
This determines which set of motor parameters is used by the drive.
00 : Motor parameters for a Hitachi standard motor
(Uses [H020] ~ [H024] )
01 : Use auto tuning data
(Uses [H030] ~ [H034] )
02 : Use auto tuning data with On-line auto tuning
On-line auto tuning occurs every time the inverter stops. It
measures R1 and R2, the main values that may change
due to a motor temperature change. The tuning period is roughly
5 seconds maximum, and if the RUN command is given during
the tuning routine, the inverter will start and tuning is aborted.
This sets the motor kW, not a kW of an inverter.
Controls the
speed response
Ÿ Large K à Quick response (Too high a value can cause instability.)
Ÿ Small K à Slow but stable response
Value is also dependent on Proportional gain (P-gain : [H050])
and Integration gain (I-gain : [H051]). ( K = f(Kp, Ki) ).
This should be adjusted in case of motor instability.
Increase / decrease depends on the situation.
Influences mainly the
torque at low
Ÿ
Large R1 à Higher torque (Too high R1 à Over magnetizing)
Ÿ
Small R1 à Smaller torque
Influence mainly on the speed change ratio (=
Ÿ
Large R2 à Increase speed change ratio
(= Actual speed becomes faster than a target speed.)
Ÿ
Small R2 à Decrease speed change ratio
(= Actual speed becomes slower than a target speed.)
5
Remarks
speed.
slip
compensation)
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