NAVIS NavDP 4000 Series, Руководство по эксплуатации

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NAVIS NavDP 4000. Operation Manual
Figure 6.22: Waterjet thrust indicator
6.2 Thruster Operation
6.2.1 Thruster status
Each thruster can be:
– not available for DP operation.
The corresponding thruster softkey is grey or red.
– available for DP operation from Manual Thruster Window. The corresponding thruster softkey is dark green.
All such thrusters are the elements of the Manual Thruster Group, and each thruster is controlled separately from
the others.
– available for DP operation from Auto Thruster Window.
The corresponding thruster softkey is light green. All such thrusters are the elements of the Auto Thruster Group,
and the thrust demand to each thruster is assigned by the Thruster Allocation Function.
A round status indicator is displayed for each thruster that monitors whether the thruster can be taken to auto control
status or not. This indicator is color-coded:
Green color means that the thruster can be taken to auto control status or have been already set in this status.
Red color means that the thruster cannot be taken to auto control status because the control is failed.
White color means that the thruster cannot be taken to auto control status because it is not available for this control mode.
6.2.2 Thrust Demand
The Thruster Allocation Logic distributes the thrust demand (force and moment) between automatically controlled
actuators.
Dealing with a thruster, NAVIS NavDP 4000 operates in term of its thrust, in whatever way the thrust is produced.
NAVIS NavDP 4000 receives feedback signals (rpm, pitch, azimuth angle, rudder angle etc.) and calculates the actual
thrust.
The value of the actual thrust is then indicated in % to maximum. Those propulsion parameters which produce
the thrust (i.e. rpm, pitch, azimuth angle, rudder angle etc.), are also indicated in numerical form. When controlling a
thruster,
NAVIS NavDP 4000
calculates the
thrust demand
. The thrust demand is then transformed to desired propulsion
parameters (i.e. desired rpm, pitch, azimuth angle, rudder angle etc.), and these parameters come from NAVIS NavDP
4000 at the input of the thruster control system.
Independently of the number of the thrusters and their types and locations, their effect on the vessel can be described
by the vector force F and the rotational moment M .
If the vessel’s position is controlled manually, with the joystick, the demand for F is calculated accordingly to the
joystick position. If the vessel’s position is controlled automatically, the demand for F is calculated by means of a
particular control algorithm, dependently on the control mode activated.
If the vessel’s heading is controlled manually, with the rotary knob, the demand for M is calculated accordingly to the
knob angle. If the vessel’s heading is controlled automatically, the demand for M is calculated by means of a particular
control algorithm, dependently on the control mode activated.
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Doc. 000.JDP-10000-OME, rev.3.3.13/“2102.$–17A-Advanced”