WÄRTSILÄ 46DF, Руководство по эксплуатации продукта

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Wärtsilä Unified Controls – UNIC is a modular embedded automation system. UNIC C3 is
used for engines with electronically controlled fuel injection and has a hardwired interface for
control functions and a bus communication interface for alarm and monitoring.
14.5 Guideline for electrical and automation system
Load increase during ship acceleration, manoeuvring, and load transfer between generators
must be controlled according to instructions in chapter 2.2 Loading Capacity. The total load
increase rate on a recently connected generator (preheated engine) is the sum of the uploading
that is performed by the load sharing control and by the propulsion control.
Fastest possible loading up to high load in diesel mode should only be available by activating
an “emergency loading” function, which is indicated by an alarm in the control room and on
the bridge. In applications with highly cyclic load, e.g. dynamic positioning, maximum loading
can be used in operating modes that require fast response. Other operating modes should
have slower loading rates. Maximum possible loading and unloading is also required for e.g.
tugs.
Load reductions from high load must be rate limited in normal operation as described in chapter
2.2 Loading Capacity. Crash stop can be recognised by for example a large lever movement
from ahead to astern. In the low load range, which is typically used during manoeuvring, the
load can be reduced without rate limitation.
The response to increase and decrease pulses from PMS or synchroniser is 0.1 Hz per second
by default, but the rate is adjustable. This is the rate for the speed setting. Actual speed and/or
load change at a much slower rate, especially when the adjustments are small. Recommended
deadband for load balancing (PMS control) is ±2% of rated power.
The engine can absorb 5% reverse power. Recommended setting for the reverse power
protection is 5% of rated power with 10 s delay.
There can be significant load swings between parallel generators in gas engine installations
(short peaks, frequency >1.5 Hz). This is a harmless phenomenon, which is caused by cycle
to cycle variations in cylinder pressure when the engines run on gas fuel. Load limitation and
load reduction functions should therefore act on the average generator load, not short spikes
on individual generators. It is however recommended to monitor also network frequency,
because it is possible that an engine loses power, but not to the extent that the generator trips
on reverse power. In such a situation the average power is on an acceptable level, but the
parallel engines might still be overloaded.
The load should be kept as stable as possible while an engine is transferring from diesel to
gas mode. Since the engines are running in speed control, they will all respond to rapid load
changes. The load variations on a transferring engine can be significantly reduced (but not
totally eliminated) by running the transferring engine in speed droop and the parallel engines
in isochronous load sharing mode.
DBAD209883 14-9
14. Automation System Wärtsilä 46DF Product Guide