Eaton SVCH0203 SPX Advanced, Руководство по применению

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SPX advanced – description of parameters
SPX ADVANCED APPLICATION MANUAL
SVCH0203—October 2017 www.eaton.com
5.8.3 Permanent magnet synchronous motor settings
There are three ways to know the magnet positions when
using the closed loop control. The first one will identify
the motor magnet position during every stat when using
incremental encoder without Z-pulse.
Second one uses incremental encoder Z-pulse and the
third one uses absolute encoder information. See details of
selecting correct mode from chapter “Identification function
for permanent magnet synchronous motor”.
Code ID
Parameter
Notes
P1.8.6.1 649 PMSM shaft position “PMSMShaftPositio”
Absolute encoder position value corresponding to the shaft position where rotor
magnet axis is aligned with the stator U-phase magnet axis will be stored here as a
result of the encoder identification run. If incremental encoder with a z-pulse is used,
z-pulse position will be stored instead. Depending on the motor shaft mechanical
position, this parameter can have different values, as there is one right value for each
pole-pair of the motor. If incremental encoder and the z-pulse is utilized, the first start
after power up is less optimal and i/f-control (see 6.8.3.2) will be used until the drive
finds the z-pulse and is able to synchronize in that.
P1.8.6.2 1691 Start angle Identification Mode “StartAngleIdMode”
Start angle, i.e. rotor magnet axis position in respect to the stator U-phase magnet
axis, identification is needed if there are no absolute encoder or incremental encoder
with z-pulse used. This function defines how the start angle identification is made
in those cases. Identification time depends on the motor electrical characteristics
but takes typically 50ms...200ms. In case of absolute encoders, start angle will
read directly from the encoder absolute angle value. On the other hand, incremental
encoder z-pulse will be used automatically for synchronization if it’s position is defined
different from zero in P1.8.5.1. Also for absolute encoders, P1.8.5.1 must be different
from zero, otherwise it is interpreted that the encoder identification run has not been
done and the running will be prohibited except if the absolute channel is bypassed by
the start angle identification.
0 = Automatic
Decision to use start angle identification is made automatically based on the encoder
type connected to the drive. This will serve common cases.
Supports: OPT-A4, OPT-A5, OPT-A7 and OPT-AE boards.
1 = Forced
Bypasses the drive automatic logic and forces the start angle identification to be
active. Can be used, for example, with absolute encoders to bypass absolute channel
information and to use start angle identification instead.
2 = On Power UP
As a default, start angle identification will be repeated in every start if the
identification is active. This setting will enable identification only in a first start after
drive is powered up. In consecutive starts, angle will be updated based on the encoder
pulse count.
10 = Disabled
Used when Z- pulse from encoder is used for start angle identification.
ModulatorType (P1.10.2) need
to be > 0 to be able to use this
function.
P1.8.6.3 1759 Start angle identification current “StartAngleIdCurr”
This parameter defines the current level that is used in start angle identification. The
correct level depends of the motor type used. In general, 50% of motor nominal current
seems to sufficient, but depending for example on the motor saturation level, higher
current might be needed.
P1.8.6.4 1566 Polarity pulse current “PolarityPulseCur”
This parameters defines the current level for the magnet axis polarity direction
check during the start angle identification (P1.8.5.2). Value 0 means that the internal
current level is used, which is typically slightly higher than the normal identification
current defined by P1.8.5.3. Polarity direction check is seldom needed because
the identification itself gives already the right direction. Hence in most cases, this
function can disabled by setting any negative parameter value, which is recommended
especially if there occurs F1 faults during the identification.
P1.8.6.5 1755 Start Angle Identification Time “StartAngleIdTime”
Start angle can be determined also by feeding dc-current into the motor. Then
dc-current will align the rotor magnet axis with the stator magnet axis. This function is
activated by determining the time duration dc-current is injected to the motor. Motor
must be free to move during the alingment and the time need to be long enough for
shaft oscillations to damp out. Hence, this method is not so pracatical and is intednded
to be used mainly for testing purposes or to improve starting in together with i/f-
control. Dc-current level is determined by P1.8.5.6. Also P1.8.5.2 need to disabled
otherwise overriding this function.