Beckhoff TS5066, Руководство пользователя

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PLC API
TS5066 18 Version: 1.0
Fig. 11: Figure 2: Overview of the situation, shown enlarged in Figure 1.
Extrapolation of the set values
Two techniques that differ in terms of detail are available for extrapolation of the set values. The first
technique only uses the set velocity for extrapolating the set position:
AxisOut.fPosSoll:=AxisIn.fP AxisIn.fVeloSoll * fTimeCorrection;
AxisOut.fVeloSoll:=AxisIn.fVeloSoll;
Furthermore, the set acceleration may also be used for extrapolating the set position and set velocity:
AxisOut.fPosSoll:=AxisIn.fP AxisIn.fVeloSoll*fTimeCor 0.5 * AxisIn.fAccSoll
*fTimeCorrection^2;
AxisOut.fVeloSoll:=AxisIn.fVe AxisIn.fAccSoll *fTimeCorrection;
Requirements:
Depending on the main mode in which the axis is to be operated, certain requirements have to be met, and
the associated mode has to be activated. The corresponding combinations are shown in Table 1.
Main axis operating
mode Parameters required in
AxisIn Parameters Comment
Position interface Set position
Set velocity
(set acceleration)
stAxisExtrapolateParamet
ers .bUseAccForExtrapola
tion=FALSE
(=TRUE)
Acceleration can
optionally be added as a
parameter. (The
acceleration requirements
described above must be
met.)
Velocity interface Set position
Set velocity
Set acceleration
stAxisExtrapolateParamet
ers .bUseAccForExtrapola
tion=TRUE Analytical acceleration
behaviour required, i.e. no
encoder axes, for
example
Operating modes:
In addition to set value extrapolation, further operating modes are available. Two of these (bypass mode and
PT1 mode) are mainly used in cases where no correction time is available for the extrapolation. If the
function block
FB_TimeSync [ } 14] is used this is the case during the initialization phase or if synchronization
fails for other reasons. This block can also be used with an optional time mode that enables a correction time
for avoiding fluctuations to be determined during initialization without knowledge of the beat frequency.