CIMAC Congress - Schiff & Hafen

Monday, 14 June
Tuesday, 15 June
Thursday, 17 June
Wednesday, 16 June
Applying close loop control, ‘Auto-tuning’,
to MAN Diesel two-stroke engines
T. Moeller, MAN Diesel & Turbo SE, Denmark
This paper will introduce the development and technical
description of closed loop engine control, ”Auto-tuning”, and
furthermore demonstrate the service experiences and conclusions
gained from applying the concept to MAN Diesel two-stroke ME
as well as MC engine types. The continued focus on reducing fuel
oil consumption, emissions and overall operational costs has,
combined with availability of new reliable technologies, allowed
for development of new systems to more effectively obtain results
in these areas. One of the means is the MAN Diesel ”Auto-tuning”
concept, that by clever innovation addresses all of the areas,
without adding considerable system complexity and installation
costs - as otherwise is typically the case of other concepts. The later
years progresses in sensor technology have made high accurate &
reliable sensors with long life time available for two-stroke
applications. The MAN Diesel ”PMI online” system for continuous
cylinder pressure measuring, utilises sensors provided by either
ABB or Kistler. With the MAN Diesel ”Auto-tuning” concept, our
”PMI online” system is integrated into the engine control system
(electronically controlled engines) for continuous close-loop
tuning of the engine. This paper will discuss and present the
challenges identified as well as the full scale field test results
observed in respect to which of the traditional key parameters
(Pmax, Pcomp, PI) that from a cost benefit approach is target for
being auto-tuned. Not only actual engine type and layout
influences this targeting, also safety issues, transparency of the
tuning process towards the operator, remote tuning opportunities
and strategy for handling the non-linearity of the process to be
adjusted is among the aspects to be taken into account. The paper
primarily focuses upon applying ”Auto-tuning” to electronically
controlled engines. However, the additional challenges to
overcome by introducing ”Auto-tuning” also for conventional
engines with camshaft operated fuel plunger and exhaust valves is
outlined. For these engines, the existing VIT (Variable Injection
Timing) is replaced by a continuous close loop control of the VIT
actuation, integrated with the Auto-tuning system. The MAN
Diesel developed concept for ”Auto-tuning” is capable of
optimising operation of the engine to well within the
recommended maximum deviation and operation limits, thereby
allowing for an optimisation with considerable benefits to be
gained even for engines already being operated ”well” from an
traditional point of view. The optimisation is achieved even
though the ”Auto-tuning” system in fact utilises the same handles
as otherwise used by the operator for manual adjustment, at the
same time dramatically limiting the required operator efforts to
keep the engine always optimal tuned. By ensuring optimised
engine tuning, we have actively lowered operational costs, and
generally improved system efficiency. Thereby, a positive effect has
been achieved on the total fuel consumption as well as the overall
environmental impact on the surroundings. This paper will reveal
the newly developed techniques & means reaching this important
target.
The UNIC embedded controls – first years
of field experience
J. Pensar, Wärtsilä Corporation, Finland,
J. Akerman, F. Oestman, P. Juppo, Johan Grankull,
Wärtsilä Finland Oy, Finland
In 2002, Wärtsilä took a decision to develop a new embedded
control system for harsh environments as a strategic move to
ensure the performance and reliability of future products. The
requirements on the system were set very high – unsurpassed
reliability, high fault tolerance, extreme scalability and flexibility
as well as a cost efficient design were some of the objectives. The
outcome of the design eventually became known as UNIC –
Unified Controls – and was first introduced on engines in the
field in 2005. The development of the more complex features was,
however, at that time still ongoing, and the final and most
advanced applications went into commercial operation in 2008.
The design introduced novel ideas related to sensor design,
cabling, electronics, fault tolerance and redundancy that enabled
a both reliable and cost efficient design. The system also introduced
new possibilities for advanced engine control, with several
patented inventions related to e.g. engine speed/load control as
well as fuel injection, pushing the envelope for what can be
considered state-of-the-art in engine controls. It should, however,
be remembered that only the real-world experience will show the
actual reliability of the system. Today this system has been
delivered with thousands of engines and has acquired more than
five million cumulative operation hours in the field. This gives us
now the opportunity to review how well the design ideas and
assumptions have turned out in practise and how well the system
has withstood the test of the realworld. This paper guides us
through the project, focusing not only on the aspects and
assumptions that turned out to be successful, but also on the
problems, failures and rework that occurred during the
introduction process. Based on this experience, some important
lessons can be learned for future work. In addition, this paper also
reflects on the future development of controls, looking towards
the future on both embedded controls and its relation to the Big
Picture, i.e. efficient system integration and total solutions.
AVL EPOS TM – OPEN AND SCALABLE
ENGINE CONDITION ANALYSIS SYSTEM
No. 3 | 2010 | Ship & Offshore
69