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Technology

VCM’s bright future on the seaTests prove it: the flexibility and efficiency of ABB Turbocharging’sValve Control Management (VCM) has important benefits formarine applications. Gas and dual-fuel engines are the specialareas in which VCM has a most promising future.

Text Tiziana Ossola Auf der Maur, Photography Michael Reinhard

Two words best describe thetechnical benefits of ABB Turbocharging’s Valve ControlManagement (VCM): flexibility

and efficiency. To be precise, VCM allowsengine valve timings to be varied at allengine loads to control engine emis-sions, while at the same time improvingengine response, idling and startingbehavior. The result is, above all, a signif-icant fuel saving.

In 2009 ABB Turbocharging took upthe challenge of applying this technologyto large engines. To achieve this aim, itforged a development partnership withthe German company Schaeffler, a provenspecialist in the field. Schaeffler’s UniAir-System is an electro-hydraulic, variablevalve control system developed forsmaller internal combustion engines andalready running in hundreds of thou-sands of cars.

Fast load changes enabledThe results of the engine tests that

ABB Turbocharging has conducted havebeen extremely positive. In fact, as ABB Turbocharging VCM project leader

Ville Pellinen notes, “In many respects,the results are better than we wereexpecting.” The operating principle ofABB’s VCM system distinguishes itselffrom other, existing solutions, in a num-ber of ways. “We can vary the amount ofair reaching the engine any time we like,”Pellinen adds. “Each cylinder is able towork differently thanks to the rapid varia-tion in valve timings in every singleengine working cycle.”

This VCM principle opens up a widearea of potential applications on marineengines – for example in offshore shipsor passenger ferries. Generally speaking,VCM is of assistance wherever fast loadchanges are expected of engines on aregular basis. Pellinen continues: “VCMenables engine power to be changed by50% within fractions of a second. And it also provides a tremendous powerreserve at lower engine speeds. In thefuture, many vessels could be fitted withsimpler fixed pitch propellers (FPP)instead of controllable pitch propellers(CPP). This would reduce both the firstcosts and the operating costs associatedwith the much more expensive and com-plex CPP alternative.”

In addition, ABB Turbocharging’s testsshow that VCM considerably improvesgas and dual-fuel engine combustion.Efficiency increases of 1.5% – corre-sponding to a 3% lower fuel consump-tion – have already been demonstratedon engines with VCM. In combinationwith ABB Turbocharging’s high pressure,high efficiency two-stage turbochargingPower2, VCM also enables a further

VCM: Benefits at a glance

– Significant fuel saving– Especially helpful in marine appli-

cations with frequent and fast loadchanges

– Increased tolerance of differentfuel qualities and ambient condi-tions

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Technology

increase in engine power and additionaloperating robustness. Gas and dual-fuelengines with “diesel-like” performanceare within reach with very strong, con-trolled Miller cycle combustion. The highpressure, efficiency and flexibility ofPower2 and VCM complement each other here.

VCM compensates for low gas qualityCurrently, only about 60% of the

worldwide liquefied natural gas (LNG)supply is of a high enough quality toallow full power operation on the currentgeneration of gas engines. Further, gasquality is expected to diminish in thefuture. In the worst case, a bigger enginewill need to be installed in order to com-pensate for the reduction in powerpotential due to low gas quality. “In somecases VCM even allows an engine withfewer cylinders to be used. That, ofcourse, also translates into a saving infirst and operating costs,” Pellinen says.

Political decisions that increase therelevance of LNG are on the way. Thelimitations for oxides of nitrogen (NOx )and sulfur (SOx ) in Northern Europe, theUSA and Canada are boosting the use ofgas or dual-fuel engines, since commer-cial LNG is not just a “low-NOx” fuel, but also a “no-sulfur fuel”. LNG is set tobe an economically viable alternative toliquid fuels by 2020/2025 – when it isplanned to introduce worldwide limits –especially when compared with the alter-native of relatively expensive diesel oiland aftertreatment equipment. Also, theEU is set to provide LNG refueling pointsfor maritime and inland waterway trans-port at 139 ports in the Trans-EuropeanTransport (TEN-T) core network by2025/2030. This is an important step forboth the shipping industry and the harbors themselves. For VCM projectleader Pellinen it goes without sayingthat “ABB Turbocharging is equipped toface a future in which the significance ofLNG will grow.”

VCM is of assistancewherever fast loadchanges are expected ofengines on a regularbasis.

VCM enables engine power to be changed by 50% within fractions of a second.