Marine Installation Manual
2021-08
6-20
6 Engine Dynamics
6.8 Countermeasures for dynamic effects
X72DF
SPS is used to compensate one of the following:
•
Second order vertical mass moments (M
2V
•
Lateral H-type guide moments discussed in section
•
Excitations generated by the blade frequency of the propellers
Components and control
The speed and the crank angle of both engines are measured by control units,
which are installed on the engines. These signals are continuously transmitted to
the Synchro-Phasing main controller, where the relative position and speed be
-
tween the two engines is measured.
Figure 6
-
12 Synchro-Phasing system
Main controller and
user interface in ECR
The main controller is installed in the engine control room along with the user in
-
terface, where the relative phase difference angle (provided by WinGD vibration
experts) can be entered. This enables the system to implement a closed loop con
-
trol of the set-points, which are a function of the difference between the reference
phase angle and current phase angle. To adjust the phase angle between the two
engines, the speed of only one (slave) engine is adapted.
The additional components required are:
•
Control unit (x2)
•
Synchro-Phasing main controller (x 1)
•
User interface (x1)
NOTE
The compensation is only capable of neutralising one selected fre
-
quency at a time.
SM-0516
Synchronisation
Engine Control Room
Engine 1
Engine 2
ECS
ECS
PCS 1
PCS 2
User
Interface
Synchro-Phasing
Main Controller
Control
Units
Control
Units
