P No.
Index Name
Unit Description
792
2
d-Amplitude sinus
A
SC test signal: d current amplitude of sinusoidal
signal
792
3
q-Amplitude sinus
A
SC test signal: q current amplitude of sinusoidal
signal
792
4
PRBS time
ms
SC test signal: PRBS signal time
792
5
d-Amplitude PRBS
A
SC test signal: d current amplitude of PRBS
signal
792
6
q-Amplitude PRBS
A
SC test signal: q current amplitude of PRBS
signal
792
7
Full signal range
rpm SC test signal: Full test signal amplitude range
792
8
Increasing signal range
rpm SC test signal: Linear transition range up until
which the test signal is reduced to 0
792
9
d-current offset
A
SC test signal: d current offset of sinusoidal
signal
794
ENC_CH4_Kalman_
ICOM
Sensorless control: Auto commutation
794
0
SettlingTime
ms
SC auto commutation: Rise time
794
1
ICOM_current
A
SC auto commutation: Current offset
794
2
ICOM_time
ms
SC auto commutation: Time ( 0 = OFF)
794
3
ICOM_1st_L_ident
mH
SC auto commutation: First measured
inductance
794
4
ICOM_2nd_L_ident
mH
SC auto commutation: Second measured
inductance
796
ENC_CH4_Kalman_isd_
add
Sensorless control: Additive load-dependent d
current
796
0
Amplitude
A
SC load-dependent d current: Amplitude
796
1
Full signal range
A
SC load-dependent d current: q current at which
the maximum d current is injected
796
2
Increasing signal range
A
SC load-dependent d current: Transition range
up until which the d current is reduced to 0
796
3
PT1_Tfil
ms
SC load-dependent d current: Filter time for d
current (PT1)
797
0
ENC_CH4_Kalman_
Compare
Sensorless control: Reference encoder
selection
Table 6.29: “Sensorless synchronous motor control” parameters (continue)
MOOG
ID
No.:
CB40859-001
Date:
02/2018
MSD Servo Drive - Device Help
90
6 Encoder
6.8.1.1 Auto commutation
When using sensorless control, auto commutation is required in order to ensure
that the motor will not align itself towards a direction in an uncontrolled manner.
There are two options for commutating the motor when using sensorless operation:
6.8.1.1.1 Mode 1 (default method for non-braked motors)
This mode uses the “Current injection (IENCC)” default auto commutation from
P 390[0] - CON_ICOM.
If the encoder selection set with P 520[0] - ENC_MCon, P 521[0] - ENC_SCon and
P 522[0] - ENC_PCon has been set to channel 4, the commutation angle will be set
to 0 at the end of the alignment phase, as the motor will be in the d axis at this point.
6.8.1.1.2 Mode 2
In this auto commutation mode, a positive measuring current and a negative
measuring current are injected into the motor in order to take inductance
measurements. The measured inductances can then be used to determine whether
the motor is in an unstable rest position. The identified values will be entered in
P 794[3] - ICOM_1st_L_ident and P 794[4] - ICOM_2nd_L_ident. It is necessary to
ensure that the two values are sufficiently different from each other. If the difference
is too small, you can increase the amplitude. However, please note that excessively
large amplitudes can result in the motor being demagnetized if auto commutation is
used frequently. In case of doubt, ask the motor manufacturer what the maximum
permissible current is.
P 792[1] - Frequency and P 792[2] - d-Amplitude sinus will be used as the
measuring frequency and measuring amplitude. In addition, P 794[0] - SettlingTime,
P 794[1] - ICOM_current and P 794[2] - ICOM_time need to be configured.
