DE102013108161B4 - Method for operating a double-ended ferry - Google Patents

Abstract

Method for driving a double-ended ferry (1), wherein in each case at least one rudder propeller (2a, 2b) is provided in the region of the bow (10) and the stern (11), which is driven by an associated drive system (3) which drives an internal combustion engine (3). 30) and an electric motor (32) and with a control device (5) for independent control of the drive systems (3) for the Rudderpropeller (2a, 2b), characterized in that the internal combustion engine and the electric motor of each drive system (3) independently by means of the control device (5) are controlled, such that when the double-ended ferry (1) moves, the rudder propeller ahead in the direction of travel by means of the electric motor (32) of the associated drive system (3) and the other rudder propeller by means of the internal combustion engine (30) of the associated drive system (30). 3) is driven and in positioning the Doppelendfähre (1) all Rudderpropeller (2a, 2b) by means of the zugeordne th electric motors (32) are driven.

Description

The invention relates to a method for driving a Doppelendfähre wherein at least one rudder propeller is provided in the region of the bow and stern, which is driven by a respective associated drive system comprising an internal combustion engine and an electric motor and with a control device for independent control of the drive systems for the rudder propellers.

Double-ended ferries of the type mentioned in the introduction are known and are used, for example, as car ferries on rivers and lakes or as sea-going vessels in the vicinity of the shore, e.g. used to islands or in fjords.

Double-ended ferries with a maximum system output of 1,200 kW are mainly equipped with rudder propellers, which are directly driven by a diesel engine, usually via a cardan shaft. Gas or diesel-electric drive systems are only used for larger outputs, but they also result in significantly higher installation costs.

Classic double-ended ferries are propelled by two rudder propellers, each with an arrangement arranged in the bow or stern of the ship. The Rudderpropeller be operated at service speed and route usually with significantly different power consumption. The plant lying ahead in the direction of travel is operated only at low speed and power, while the other, eighth plant applies between 70 to 85% of the total required drive power. This different performance query of a double-ended ferry is due to this, otherwise there are unfavorable effects on the total power requirements of the ferry. These result essentially from two effects. On the one hand, the accelerated propeller jet of the plant lying ahead in the direction of travel leads to an increase in the resistance of the ferry due to an increase in the frictional resistance due to the accelerated flow around the fuselage and an increase in the pressure resistance, which depends on the respective installation situation. On the other hand, the increased flow velocity at the other, aft lying plant to a reduced thrust / power ratio, so that the ship grade decreases. The extent necessary low power consumption in the direction of forward rudder propeller drive system has an unfavorable operating condition of the diesel engine result, both in terms of specific fuel consumption and on the pollutant emission. Such an unfavorable partial load operation with only 15 to 30% of the lay-out performances accounts for a considerable proportion of the total operating time, in particular if the time at the pier for loading and unloading is taken into account. It should be noted that ferries at the pier during loading and unloading are usually not fixed in the ferry service, which is why the ship with the propulsion systems at the pier must be kept and this also results in a mostly low thrust and thus power requirements.

The DE 10 2008 037 114 A1 describes a drive system in which driving on the line, depending on the direction of travel always drives the rear propeller. The front engine associated diesel engine drives the associated electric motor as a generator, which in turn provides power to the rear electric motor. The rear system that propels the ship generates the power from the combined operation of the diesel engine and the electric motor. A division of the propulsion power front / rear is hereby not possible, also has the conventional propeller a preferred thrust direction. A departure from the preferred thrust direction means a large loss of efficiency.

Furthermore, JP H09-58 580 A describes the use of rudder propellers for driving double-ended ferries.

From the DE 44 30 409 A1 and the DE 20 2004 020 606 U1 Ferries are known in which the front drive is operated with a lower power than the rear. The object of the invention is therefore to propose a method for driving a double-ended ferry of the type mentioned, which is characterized by a particularly economical and environmentally friendly drive, which is also very flexible in operation and designed with high redundancy.

To achieve the object, the embodiment is provided with the features of claim 1 according to the invention.

Advantageous embodiments and modifications of the invention are the subject of the dependent claims.

The invention proposes to drive the internal combustion engine and the electric motor of each drive system independently of each other by means of the control device, such that when driving the double-ended ferry ahead in the direction of travel rudder propeller is driven by the electric motor of the associated drive system and the other Rudderpropeller means of the internal combustion engine of the associated drive system and in positioning the Doppelendfähre all Rudderpropeller be driven by means of the associated electric motors.

According to the invention, each drive system associated with the rudder propellers comprises an internal combustion engine and additionally an electric motor, so that a hybrid drive is provided which is provided for driving the associated rudder propeller, wherein the internal combustion engine and the electric motor can be controlled independently of one another by means of the control device. According to the invention, it is provided that the control device is set up to drive the rudder propeller ahead in the direction of travel during travel of the double-ended ferry by means of the electric motor of the associated drive system and the other rudder propellers by means of the internal combustion engine of the associated drive system, resulting in particularly advantageous operating states. In this case, namely, in the direction of travel lying ahead, arranged in the bow area Rudder propeller can be operated as before with only low power consumption, which can be provided by a correspondingly dimensioned electric motor emission-free without further notice. The main drive power is still generated at the aft lying further drive system, by the existing there in the drive system internal combustion engine, which can be driven in the optimum power range.

In addition, it is provided that the control device is set up so that in positioning the Doppelendfähre about lying time at the pier for loading and unloading all Rudderpropeller be driven by means of the associated electric motors, so turned off during this time, the diesel engine both propulsion systems, thus fuel and emissions can be saved and the low required drive power is provided exclusively by the respective electric motors of the drive systems.

The provided in the embodiment of the invention on the two drive systems electric motors are designed with respect to their nominal point for a much lower speed, but can be operated at constant power and up to the maximum speed of the diesel engine.

According to one proposal of the invention, the electric motors of the drive systems have a rated power corresponding to about 60 to 70% of the rated power of the installed diesel engine or between 35 to 40% of the total installed per rudder propeller power, whereby the electric motor is able to both in Positioning operation as well as driving in the course of the drive in the direction of travel upstream rudder propeller to apply the required drive power.

This design results essentially from the requirements of the stall thrust, the usual power ratings of available combustion, especially diesel engines and the intention to be able to use a smaller size of the internal combustion engine.

According to a proposal of the invention, the electric motor is integrated directly into the shaft line of the internal combustion engine, wherein alternatively it is also possible to drive the electric motor via its own drive shaft the rudder propeller or to drive the rudder propeller via a belt drive.

With the possible use according to the invention of an additional electric motor per drive system of the rudder propellers, the pronounced part-load operation of the drive system of the associated rudder propeller lying ahead in the direction of travel can be avoided. The number of operating hours of the internal combustion engine drops considerably and the maintenance intervals increase. In addition, the internal combustion engine can usually be chosen smaller than in the prior art.

In addition, there is the advantage that after failure of an internal combustion engine within a drive system additional redundancy is given, so that minor repairs or service work are possible with almost no restrictions of the normal ferry operation.

Another advantage of the present invention per drive system additionally provided electric motors can be seen in the very good controllability of the thrust for arrival and Ablegemanöver. The electric motor has in contrast to the internal combustion engine no fixed idle speed and can be driven at a freely selectable speed, so that the otherwise required wear and consumption-intensive slip clutch is eliminated and the thrust can be very sensitively regulated.

Furthermore, it is possible for the control device to be set up in such a way that the rudder propellers are driven jointly by the electric motor and internal combustion engine of the associated drive device so that, on the one hand, a boost mode can be realized in which the diesel engine is coupled to the electric motor during high thrust demands can be, resulting in a significantly higher available torque, especially at low speeds, which is particularly advantageous in extreme maneuvers and difficult weather conditions.

In addition, it is possible in this combined drive by means of combustion and electric motor to be able to design the internal combustion engine smaller, since the missing in comparison Drive power can be provided by the electric motor. This brings cost advantages and results in a pure combustion engine drive equivalent drive power per rudder propeller. Even this comparatively smaller internal combustion engine can be driven in the optimum power range.

Comparing the efficiency of the overall system with a diesel-electric drive concept, there are considerable advantages for the inventive design. These result mainly from significantly lower installation costs and smaller conversion losses.

A driven by the novel double-ended ferry can also be operated exclusively with electric motors of the drive systems, so that in the case of a corresponding exhaust aftertreatment existing diesel generators also low-emission operation in environmental zones can be implemented with strict conditions.

The required for the operation of the electric motors within the drive systems electrical power can be provided arbitrarily. According to a proposal of the invention, an additional generator is integrated in the electrical system or a larger generator set is used. Alternatively, the diesel generator can directly feed the frequency converter (isolated operation) and no adjustments to the vehicle electrical system or power management are required. This is particularly possible because the installed additional power is largely based on the required Propulsionsleistung and this is relatively accurate known, since it can be derived from the service speed for the operation of the ferry.

• 1 in stark vereinfachter Darstellung das Antriebskonzept einer Doppelendfähre gemäß der Erfindung;
• 2 in schematisierter Darstellung die Antriebsanlagen der Doppelendfähre gemäß 1.

Further embodiments and details of the invention will be explained below with reference to an embodiment illustrative drawing. Show it:

• 1 in a greatly simplified representation of the drive concept of a double-ended ferry according to the invention;
• 2 in a schematic representation of the drive systems of the double-ended ferry according to 1 ,

From the 1 is schematically in the supervision of a merely indicated double final ferry 1 with ship's longitudinal axis LA and a bow 10 and a tail 11 represented at the two ship ends, where the designation bow and stern in such double-ended ferries 1 is variable, since these have substantially symmetrical structure and the assignment of bow and stern essentially result from the currently selected direction of travel.

Characteristic of such double-ended ferries, however, is that they are usually in the area of Bug 10 and rear 11 each amidships, ie on the longitudinal axis LA have a rudder propeller, in the 1 is shown only schematically with 2a or 2b.

From the 2 you realize that every rudder propeller 2a . 2 B a drive system 3 is assigned to an internal combustion engine 30 , eg diesel engine with drive shaft 31 and one in the drive shaft 31 integrated electric motor 32 from which then a common drive shaft 33 to drive the rudder propeller 2a respectively. 2 B going on.

To the electric motors 32 to supply with electrical energy, a diesel generator 4 is provided, also with reference numerals 5 a control device indicated by means of which both the electric motors 32 as well as the internal combustion engines 30 both drive systems 3 for propulsion of the rudder propellers 2a . 2 B are controllable.

By means of the control device 5 in interaction with the two drive systems 3 for the Rudderpropeller 2a . 2 B are now different modes of operation of the double-ended ferry 1 realizable.

If the double-ended ferry 1 is in positioning mode, ie, for example, is located on the pier to allow loading and unloading in ferry mode, requires the double-ended ferry 1 only low drive power, for example, to keep the ship against the action of a flow at the pier.

In this operating state, which is preselected by the bridge, not shown here, activates the controller 5 only the electric drives 32 the drive systems 3 for the Rudderpropeller 2a . 2 B , depending on the power requirement, only one or both Rudderpropeller 2a . 2 B are in operation and accordingly the associated electric motor 32 Drive power outputs.

Also during the arrival and departure of the double-ended ferry 1 becomes the propulsion of the rudder propellers 2a . 2 B about the electric motors 32 causes, as these can be controlled freely and sensitively without specific idle speed and only low demand for thrust is present. In the case of high environmental forces (wind, waves, currents), the internal combustion engine can also be used if the power of the electric motors 32 should not be enough.

Goes the double-ended ferry 1 in route trip, so it moves depending on the direction of travel either with the example as a bug 10 designated end or with the tail 11 designated end ahead, so that either the rudder propeller 2a or the rudder propeller 2 B ahead in the direction of travel.

In the following, the case will be described that the double-ended ferry 1 according to 1 with the bug 10 ahead of a trip, ie the Rudderpropeller 2a is ahead in the direction of travel, while the Rudderpropeller 2 B aft lies.

In this driving condition, the controller provides 5 for that the drive system 3 of the aft propeller 2 B by means of the internal combustion engine 30 is operated while applying a 70-85% of the total required drive power, while the drive system 3 , the front of the front in the direction of travel rudder propeller 2a is assigned, only by means of the electric motor 32 is driven with the corresponding low power output, which is necessary for optimal route travel, but while the internal combustion engine 30 this drive system 3 completely switched off.

Drives the double-ended ferry 1 in the opposite direction, ie with the rear 11 advance, the control of the drive systems takes place 3 in exactly the opposite direction, ie the rudder propeller ahead in the direction of travel 2 B is exclusively via the associated electric motor 32 driven, while the then aft rudder propeller 2a by means of the internal combustion engine 30 is driven.

Alternatively, it is also possible by means of the control device 5 the aft propeller of both the internal combustion engine 30 as well as the electric motor 32 the assigned drive system 3 to let drive. In this case, the internal combustion engine usually at least one power stage can be designed smaller than required in a pure combustion engine in this operating condition, since the then missing drive power is applied and compensated by the electric motor. This brings significant cost benefits.

Of course it is also possible with very high power requirement, one or both Rudderpropeller 2a . 2 B both from the internal combustion engine 30 as well as the electric motor 32 the assigned drive system 3 to drive, so that a boost operation is realized for particularly high power requirements.

The essential advantage of the invention described above lies in the fact that at least one of the rudder propellers during route travel and in positioning operation with a correspondingly low power requirement 2a respectively. 2 B , whose drive is effected exclusively electrically and only that rudder propeller, which has a high power requirement, is driven by means of an internal combustion engine.

LIST OF REFERENCE NUMBERS

1

Double-ended

2a

Rudderpropeller

2 B

Rudderpropeller

3

power plant

4

Diesel generator

5

control device

10

bow

11

Rear

30

diesel engine

31

drive shaft

32

electric motor

33

drive shaft

Claims (6)

Method for driving a double-ended ferry (1), wherein in each case at least one rudder propeller (2a, 2b) is provided in the region of the bow (10) and the stern (11), which is driven by an associated drive system (3) which drives an internal combustion engine (3). 30) and an electric motor (32) and with a control device (5) for independent control of the drive systems (3) for the Rudderpropeller (2a, 2b), characterized in that the internal combustion engine and the electric motor of each drive system (3) independently by means of the control device (5) are controlled, such that when the double-ended ferry (1) moves, the rudder propeller ahead in the direction of travel by means of the electric motor (32) of the associated drive system (3) and the other rudder propeller by means of the internal combustion engine (30) of the associated drive system (30). 3) is driven and in positioning the Doppelendfähre (1) all Rudderpropeller (2a, 2b) by means of zugeordn eten electric motors (32) are driven. Method according to Claim 1 , characterized in that the electric motors (32) of the drive systems (3) have 60-70% of the power of the internal combustion engines (30). Method according to Claim 1 or 2 , characterized in that in each drive system (3) of the respective electric motor (32) in a drive shaft (31) of the respective internal combustion engine (30) is integrated. Method according to Claim 1 or 2 , characterized in that the electric motor (32) drives the rudder propeller (2a, 2b) via its own drive shaft. Method according to Claim 1 or 2 , characterized in that the electric motor (32) via a belt drive the rudder propeller (2a, 2b) drives. Method according to one of Claims 1 to 5 , characterized in that the control device (5) is arranged to drive the rudder propellers (2a, 2b) together by the electric motor (32) and internal combustion engine (30) of the drive device (3).

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