FI86395C - FARTYGS DRIFTSYSTEM. - Google Patents

Description

1 86395

Ship operating system

The invention relates to a propulsion system for a ship, in particular a passenger ship, having a drive shaft comprising at least one adjustable propeller directly connected to a low-speed two-stroke diesel engine acting as a drive, wherein there are at least two auxiliary diesel engines, each driven by one generator.

The required top speed for passenger ships, especially cruise ships, is well above the maximum required cruising speed. This top speed is only needed in exceptional cases; however, the operating systems must be adapted to the operating speed, which results in oversizing and, consequently, relatively poor utilization of the set engine power.

On the other hand, in order to ensure the required electrical energy output, considerably more motor power is available than is necessary, in which case the required motor power is produced exclusively by medium-speed or high-speed auxiliary motors. The set power surplus can then rise to 30-40%.

The object of the invention is to improve the utilization of the total power in onboard diesel engines. This problem • ': is solved by the present invention by inserting an electric motor / generator which draws power from the on-board network between the ship's electrical network * ... · and each diesel propulsion engine. and transfer it via the crankshaft of the diesel drive engine: further to the drive shaft or transfer the excess drive • Y; power to the ship network.

In this way, one, or all, of the drive motors can be. They are dimensioned in such a way that, taking into account the safety margin, they produce, for example, only 90% of their maximum power, the power required for the maximum required cruising speed: Y motor / generator from the mains power reserves.

5 For the most frequently required speed range, there is thus a drive system with a directly connected two-stroke diesel engine, which is characterized by low fuel consumption, low maintenance costs and the elimination of operating losses.

10 When using a synchronized machine as an engine / generator, after reaching the synchronized speed, it is appropriate to achieve increases in power output, i.e. higher vessel speeds, only by changing the angle of inclination of the adjustable propeller blade.

15 It may be appropriate to increase the RPM to the synchronized engine / generator speed with a certain excess power due to a lower vessel speed, without increasing the power available for operation by changing the angle of inclination of the adjustable propeller blade.

20 The overpower of the drive motor in synchronous speed is then converted by the motor / generator into electrical energy and made available to the on-board network. The power of the generator / diesel engine can then be reduced. Thus, an economical two-stroke diesel engine can be used to • generate electrical energy.

For this purpose, it is possible to connect a slow-running engine / generator directly to the crankshaft of the drive motor. If the dimensions of the • electrical machines required for this become too large, it can be used instead. A deceleration gear is placed between the 30 motor and the motor / generator. Must be placed between the device and the drive motor. . then a flexible switch.

The invention will now be described in more detail with reference to an embodiment.

: ·: 35 Figure 1 is a schematic representation of the new operating system.

3 86395

Figure 2, in turn, shows a partial view of an alternative to the system of Figure 1.

Figure 3 is a graphical representation showing the required power P on the vertical axis and the speed V of the vessel on the horizontal axis on the left-5a and the crankcase speed on the right-hand drive.

O

shaft speed n ^.

The drive system shown in Fig. 1 has two drive shafts 1, at each end of which an adjustable propeller 2 is arranged. The drive shafts 1 are each directly connected 10 to a diesel drive motor 3 of the low-speed two-stroke engine type; it is self-evident that instead of two drive shafts 1 there can also be only one or more.

For the supply of the ship's electrical network, which network 15 is symbolically represented by the busbar 4, there are four - or more - generators 5, each of which is driven by its own auxiliary motor 6, which is a medium-speed or high-speed four-stroke motor. The power set in this motor is so high that the electrical energy demand can be met several times, e.g. 1.25-1.5 times.

According to the invention, two engines / generators 7 are connected to the marine network 4, which in Fig. 1 are connected via a deceleration gear 8 - and in Fig. 2 directly to the crankshaft 9 of the diesel drive engine 3, whereby the flexible switch 10 in Fig. 1 enables the engine. Tor i / gene- · / ': from the crankshaft of the mechanical disconnection of the actuators. As already described, the drive motors 3 are such that, at 90% of the maximum power, they guarantee the maintenance of the maximum required cruising speed.

. ·. : This power corresponds to point 11 in the left curve of Fig. 3. Thus, the drive motors alone cover the range of the speed of the vessel, whereby e.g.

35 The power requirements for the speed range B between points ____: 11 and 12 in the left-hand part of Fig. 3 can no longer be covered by the drive motors • »· 4 86395 3 alone. According to the invention, in this area, the motor / generators 7 are further connected as motors to the crankshaft 9.

As shown on the right side of Fig. 3, the drive power 5 at point 11 is adjusted to a crankshaft speed (point 13) equal to or equal to the synchronized speed of the engine / generator 7 (Fig. 2).

The conventional speed control of the drive motors 3 per se is now arranged so that this synchronized speed is kept constant even as the power continues to increase and the required power increase is realized by changing the inclination of the adjustable propeller blade 2 in a known manner. In this way, the power required for the maximum ship speeds 12 at point 14 is achieved, whereby the power-C demand 15 is brought from the electric motor / generators 7 or the ship's network 4.

As already mentioned, with significant efficiency differences between the two-stroke and four-stroke engines 3 and 6 used, low vessel speeds can be switched at low vessel speeds, e.g. to n2 * In drive motors 3, the motor / generators 7 ... 25 supply the power reserve in area D as electrical energy to the ship's network.

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Claims (6)

A propulsion system for ships, in particular a passenger craft, comprising at least one drive shaft (2) provided with an adjustable propeller, which drive shaft is directly coupled to a long-running two-stroke diesel engine (3) as a driving machine, the driving diesel auxiliary engine (6 ), at least two for each generator (5), are arranged for the generation of the electrical energy, characterized in that an electric motor / generator (7) is arranged between the vessel's electric grid (4) and each diesel drive motor (3). which takes power from the ship's electric grid (4) which transmits it via the crankshaft (9) of the diesel drive (3) to the drive shaft (1) or which transmits excess propulsive power to the ship's electric grid (4). 2. Drive system according to claim 1, characterized in that a reducer (8) is arranged between the diesel drive motor (3) and the engine / generator (7). Drive system according to claim 2, characterized in that a coupling (10) is provided between the diesel drive motor (3) and the engine / generator (7), Drive system according to claim 1, characterized in that the engine / generator (7) and the diesel drive motor (3) are arranged in series in relation to the associated drive shaft (1). Drive system according to any of claims 1-4, characterized in that the motor / generator (7) is a synchronous machine. Drive system according to any of claims 1-4, characterized in that a power change is effected by a change of the blade of the adjustable propeller (2) when the synchronous speed (nB) of the motor / generator (7) is reached.