ABB ACS880 Series, Руководство по прошивке

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giving system some time to transit from production state to the state of fluid
drainage (typically, being the primary reason for motor to passively back-spin).
With permanent magnet type of motors, backspin speed observer function could
sustain passive monitoring of speeds not greater than half of the motor nominal
speed.
Settings and diagnostics
Parameter group 74 ESP control (page 519) .
Starting the motor
In some cases pump motor can be difficult to restart. This might be caused by
solids and/or sedimentation clogging the pump. Thus, it requires higher starting
torque to break through the blockage. Another difficulty occurs with a complex
electric circuit between drive and motor, typical for the step-up systems which
makes accurate torque production.
ACS880 ESP control program contains advanced current controller that allows
user to set directly a desired motor current reference instead of manipulating
voltage output. This enables user to achieve more accurate control over the motor
starting torque but avoid excessive voltage. The number of starting routines are
available for the user to take full advantage of the current controller benefits that
improve motor starting procedure.
￭ Kick-start
Kick-start refers to pre-magnetization of the motor before start, in the ESP systems
with step-up transformers. This is used where standard DC pre-magnetization
does not work.
The Kick-start function provides sometime for the motor to develop starting
torque sufficient to start spinning. The fast acceleration rate settings create risk
for the motor to pull out before it gets to follow the frequency reference. Instead,
the function gives current boost to motor at low speed for a set amount of time
sufficient to develop starting torque and eventually break through the static
friction.
The function allows user to set desired speed and current reference for the motor
applied for a defined period of time. After the starting routine is completed, the
drive will automatically transit to accelerate to production speed with additional
help of the Acceleration assistance (if enabled). The Kick-start function increases
the efficiency of starting routines such as Starting speed, Current pulse-start, and
Acceleration assistance.
ESP program features 49