Resolver basics and requirements
The connected resolver must meet the following criteria:
l
Ccw (positive signal progress corresponds to an anticlockwise direction
when looking at the shaft from above)
l
No transformation phase shift
l
Transformation ratio of approx. 0.5
GPOC is a special Moog online process for improving the quality of Sin/Cos
signals before they are used to calculate a position. If Sel = RES(1) or Sel = SINCOS
(2), this process may come in handy. For details see Section "Signal correction
GPOC (Gain Phase Offset Correction)" on page 74.
P No.
Index
Name / Settings
Unit Description
506
0
ENC_CH2_Sel
Interface configuration
OFF (0)
No evaluation
RES(1)
Resolver evaluation
SinCos(2)
Resolver excitation shut-off; evaluation of
a Sin/Cos encoder (max 1kHz) possible.
512
0
ENC_CH2_Num
Numerator of encoder gearing [-1...+1]
513
0
ENC_CH2_Denom
Denominator of encoder gearing [only +1]
560
0
ENC_CH2_Lines
Number of pole pairs of resolver
561
0
ENC_CH2_Corr
Encoder correction GPOC
562
ENC_CH2_CorrVal
Signal correction settings
0
Offset S2-S4 track
Offset S2-S4 track
1
Offset S1-S3 track
Offset S1-S3 track
2
Gain S2-S4 track
Gain S2-S4 track
3
Gain S1-S3 track
Gain S1-S3 track
4
Phase
Phase difference
563
0
ENC_CH2_EncObsMin
Amplitude monitoring Minimum
564
0
ENC_CH2_Info
Encoder name
565
ENC_CH2_LineDelay
µs
Correction of phase shift for cable lengths
> 50 m (only after consultation with Moog).
Table 6.15: Encoder configuration channel 2 (X6) parameters
MOOG
ID No.: CB40859-001 Date: 11/2020
MSD Servo Drive - Device Help
73
6 Encoder
P No.
Index
Name / Settings
Unit Description
0
ResExc
us
Exciter signal phase shift
Delay
us
Compensation for commutation angle
delay
566
0
ENC_CH2_Amplitude
±
Correction of amplitude for cable lengths >
50 m (only after consultation with Moog).
567
0
ENC_CH2_EncObsAct
Amplitude of analog signal
Table 6.15: Encoder configuration channel 2 (X6) parameters (continue)
The Sel and Lines parameters are self-explanatory.
Other parameters, such as Num and Denom, are described elsewhere (see Section
"Encoder gearing X6" on page 75).
l
P 561[0] - ENC_CH2_Corr
= Signal correction type
The GPOC routine used for track signal correction purposes for sine/cosine
signals is used to compensate for systematic errors. The routine is controlled
with the
Corr
and
CorrVal
parameters (see Section "Signal correction GPOC
(Gain Phase Offset Correction)" on page 74).
l
P 563[0] - ENC_CH2_EncObsMin
= Encoder monitoring minimum, sqrt
(a²+b²)
This parameter is used to scale the resolver and Sin/Cos wire break
monitoring and represents the “downwards threshold” for an error message.
The default setting is 0.2, corresponding to approx. 20% of the track signals’
amplitude (approx. 80% corresponds to approx. 1 Vss). If
EncObsMin
is set
to 0, the resolver and Sin/Cos wire break monitoring will be disabled (see
Section "Channel 1: Interface X7" on page 59 as well).
6.6.1 Compensation for long resolver cables
When using long resolver cables, there will be a phase shift between the controller’s
exciter output signal and the controller’s track input signals (S1-S3 and S2-S4). This
phase difference can be compensated for with P 565[0] - ResExc: ResExc is the
time, in µs (microseconds), by which the resolver excitation will lead. Moreover,
P 565[1] - Delay can be used to compensate for a commutation dead time, which
