Magnetek DSD 412, Техническое руководство

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DRIVE SETUP
67
Drive Set-Up
Field Regulator Set-Up
Proper control of motor field current requires
knowledge of the motor field resistance, the
electrical time constant, and the line voltage
available to control power to the motor field.
Motor field resistance is calculated from the
settings of Rated Field Volts #52 and Full
Field Current #50. The time constant and
available AC input voltage is supplied by
settings #51 and #55. If a separate source of
field circuit voltage is used, #55 should be set
at that voltage. Otherwise leave #55 set at
zero to automatically utilize the main input
voltage setting of #9. If #2 is set to ON, the
Self-Tune measured value for L/R #615 will
be used instead of #51. Verify that the above
settings are correct. The scaling of measured
motor field current is also important. Verify
that the motor field wiring is connected
correctly to the proper ampere range tap at
TB4, and that SW1 is set accordingly. Check
the calibration of measured field current, drive
display #612, against that of a separate DC
clamp-on ammeter clipped around a motor
field wire.
If motor field weakening is not required at top
speed leave WEAK FIELD CURRENT #49 set
to 40 amps or set it equal to RATED FIELD
CURRENT #50. Set STANDBY FIELD
CURRENT #53 as desired during drive idle.
If top speed is greater than the motor base
speed, set WEAK FIELD CURRENT #49 so
that actual motor voltage does not exceed the
RATED ARMATURE VOLTS #7 during a high
speed, full load run. The crossover point
between Full Field and Weak Field current will
be automatically calculated. Motor field
current will be adjusted by those settings and
measured encoder speed. The DSD 412
drive does not directly regulate armature
voltage. This is determined by field current
adjustment settings and measured rotational
speed.
Be sure to adjust motor field current so that
rated armature voltage is achieved at top
speed before attempting to set Per-Unit
Inertia.
Note:
If Field Current is set too low, the
necessary motor torque may not be available,
resulting in excessive motor armature current
or current limiting. If Field Current is set too
high, the armature voltage may exceed
voltage-limiting points, resulting in faults F407
or F408. Either condition may create an
elevator tracking error.
AC Input Voltage Requirement &
Adjustment
The line-to-line AC rms input voltage to the
drive should be greater than or equal to the
rated Full Load Armature Voltage.
To adjust the transformer taps, run the
elevator at full motoring load and rated motor
RPM. (Empty car down) During the constant
speed portion of the profile, measure the AC
voltage input to the drive (Secondary of
Isolation Transformer, #619, and the DC
Armature Voltage #610.
If the Armature Voltage is greater than the
Input Line Voltage, adjust transformer primary
taps to get the next higher voltage level on the
transformer secondary.
Speed Regulator Adjustment
The Magnetek DSD 412 drive uses a
proprietary velocity regulator called E-Reg.
This is a double speed loop encoder feedback
regulator designed specifically for elevator / lift
applications where the objective is to
smoothly follow a repeated accel/decel speed
pattern reference with a relatively fixed load.
The following characteristics are important:
Follow the reference speed with a consistent
tracking delay See Figure 16.
No overshoot at the end of acceleration
Precision speed following, including at zero
speed
Feed forward for inertia forcing
Rejection of resonant load characteristics
Ability to start with a pre-primed error to
counteract load offset roll-back
Primary adjustments for E-Reg
are:
High & Low Speed Bandwidth – #39 & 40
Sets the desired drive response from Speed
Reference changes to motor speed. Units are
Radians/sec of the closed loop crossover
frequency bandwidth. The constant time lag
characteristic of E-Reg will be 1/Response, in
seconds. Increasing the Response setting will
increase the gain to improve velocity-tracking
performance.