CN113165726A

CN113165726A - Propulsion system for marine vessel

Info

Publication number: CN113165726A
Application number: CN201980079200.1A
Authority: CN
Inventors: M·汉森
Original assignee: Borg Marine Propulsion Co ltd
Current assignee: Borg Marine Propulsion Co ltd
Priority date: 2018-12-11
Filing date: 2019-12-10
Publication date: 2021-07-23
Anticipated expiration: 2039-12-10
Also published as: EP3666639A1; CN113165726B; WO2020119945A1; EP3666639B1

Abstract

A propulsion system (10) for a marine vessel (100) is provided. The propulsion system (10) is easy to maintain, since its respective components, i.e. the electric motor (26), the thrust bearing (30) and the fluid distribution unit (40), are separately arranged and connected to each other by a plurality of couplings (32, 34). Hydraulic fluid is supplied to the impeller (24) via hydraulic conduits formed in a shaft (28, 36) of the electric motor (26). The propulsion system (10) can be used for different sizes of marine vessels and applications from light to heavy and extreme load applications by selecting appropriate components such as appropriate thrust bearings (30).

Description

Propulsion system for marine vessel

Technical Field

The present invention relates to a marine vessel, and in particular to a propulsion system for a marine vessel.

Background

Marine vessels, such as for example offshore support vessels, typically comprise one or more combustion engines driving one or more main thrusters for propulsion of the vessel. The one or more main propellers are mechanically coupled to one or more engines, for example via one or more drive shafts. One or more engines rotate at a given speed, causing a corresponding rotation of one or more main propellers. For example, a marine vessel may include a pair of diesel engines drivingly coupled to a pair of main propellers. Diesel engines and main propellers are typically operated at constant speed.

To transfer the power output of the engine to the main propeller, a gearbox may be arranged between a propeller shaft coupled to the engine and a propeller shaft coupled to the associated propeller. The gearbox is configured as a speed change mechanism changing the speed of the propeller shaft into a speed suitable for rotating the propeller shaft of the propeller.

US 9,919,780B 2 discloses a propulsion system for a marine vessel comprising a permanent magnet motor having an outer casing structure. The motor shaft is connected to a propeller shaft comprising a propeller. The thrust bearing and propeller pitch control system are integrated into a permanent magnet motor.

The present invention is directed, at least in part, to improving or overcoming one or more aspects of existing systems.

Disclosure of Invention

In one aspect of the invention, a propulsion system for a marine vessel comprises a controllable pitch propeller, a propeller shaft connected to the controllable pitch propeller, and an electric motor comprising a motor shaft drivably connected to the propeller shaft via at least a first coupling. The thrust bearing is provided separately from the electric motor and includes a support portion and a hollow shaft portion rotatably supported by the support portion. The hollow shaft portion is connected to the motor shaft via a second coupling. A fluid distribution unit is fluidly connected to the hollow shaft portion and configured to provide a flow of hydraulic fluid to the controllable pitch propeller via the hollow shaft portion, the motor shaft and the propeller shaft.

In another aspect of the invention, a marine vessel comprises a main engine or main motor and a propulsion system according to the above aspect. The main engine or main motor is configured to supply electrical energy to the electric motor of the propulsion system to drive it.

In yet another aspect of the invention, a propulsion system for a marine vessel comprises a propeller, a propeller shaft connected to the propeller, and an electric motor comprising a motor shaft drivably connected to the propeller shaft via at least a first coupling. The thrust bearing is provided separately from the electric motor and includes a support portion and a shaft portion rotatably supported by the support portion. The shaft portion is connected to the motor shaft via a second coupling. The propeller may be a fixed pitch propeller. The thrust bearing may be arranged at the front or rear of the electric motor. The propulsion system may not comprise a gear unit. Thus, the electric motor may be directly coupled to the propeller shaft via the first coupling with the thrust bearing arranged in front of the electric motor, or the electric motor may be directly coupled to the propeller shaft via the second coupling, the thrust bearing and the first coupling with the thrust bearing arranged in rear of the electric motor.

Other features and aspects of the present invention will become apparent from the following description and the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate exemplary embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings:

fig. 1 shows a partial side sectional view of a marine vessel comprising a propulsion system according to the invention.

Fig. 2 shows an enlarged partial view of a thrust bearing according to the invention.

Detailed Description

The following is a detailed description of exemplary embodiments of the invention. The exemplary embodiments described herein and illustrated in the figures are intended to teach the principles of the present invention so that those of ordinary skill in the art can apply and use the invention in many different environments and for many different applications. Accordingly, the exemplary embodiments are not intended to, and should not be construed as, limiting the scope of patent protection. Rather, the scope of patent protection is defined by the appended claims.

The present invention may be based in part on the following recognition: to meet requirements such as quiet operation of marine vessel propulsion systems and reduced mechanical and energy conversion losses, it may be necessary to provide an electric motor to drive the main propeller of the vessel. In particular, it has been realized that this may be achieved without providing a reduction gearbox system between the electric motor and the propeller shaft of the propeller.

Furthermore, it has been recognized that integrating thrust bearings and/or fluid distribution units into the electric motors of the propulsion system, for example, limits the application of the propulsion system to light and small vessels because the integrated thrust bearings cannot receive the loads associated with heavy and large vessels. Furthermore, it has been recognized that integrated systems are unnecessarily complex and difficult to service and maintain.

It has therefore been recognized that it is advantageous to separate the various components of the propulsion system, in particular the electric motor, the hydraulic unit and the thrust bearing. This allows the system to be used in any size vessel, for example, small to medium to large vessels, and applications operating from light to heavy and extreme loads. In this way, the propulsion system is easier to repair and maintain, and the replacement of individual components is also easier. In some cases, components of the system may be replaced in the field without interrupting the operation of the vessel.

Furthermore, it is also recognized that the propulsion system disclosed herein may be retrofitted onto a marine vessel, for example by providing the propulsion system in a wing attached to the vessel hull. In some applications, multiple propulsion systems and corresponding wings may be provided to achieve a desired output power.

Furthermore, it has been realized that the propulsion system is particularly advantageous when using a controllable pitch propeller, since hydraulic lines for supplying hydraulic fluid to the controllable pitch propeller may be provided within each shaft of the propulsion system, which are suitably coupled to each other to enable a fluid connection between, for example, a control chamber in the hub of the propeller and a fluid distribution unit, which may be arranged in front of the electric motor and the propeller shaft.

In the following, an exemplary propulsion system for a marine vessel is described with respect to fig. 1 and 2. Fig. 1 shows a partial side cross-sectional view of a marine vessel 100 having a propulsion system 10, and fig. 2 shows an enlarged partial view of the propulsion system, illustrating a thrust bearing according to the invention.

As shown in fig. 1, a marine vessel 100 (which may be an arctic vessel, such as an arctic tender or multi-purpose offshore vessel) includes a hull 14. Further, the marine vessel 100 includes one or more main engines or motors 20. Each main engine 20 may be an internal combustion engine configured to combust a gaseous and/or liquid fuel supply to produce a mechanical output. For example, each primary engine 20 may be a diesel engine, a gaseous fuel engine, or a dual fuel engine configured to combust a gaseous fuel and a liquid fuel (e.g., diesel). Alternatively, each main engine 20 may be configured as an electric motor powered by a generator. Each main engine 20 may be a variable speed engine configured to operate at different speeds, or may be a constant speed engine configured to operate at a constant speed.

An alternator (not shown) may be mechanically connected to main engine 20. For example, the input of the alternator may be mechanically connected to a flywheel (not shown) of the engine 20. The alternator may be configured to receive mechanical output from the associated engine 20 and convert it to electrical energy. The electrical energy generated by the alternator may be provided to an electric motor 26 of the propulsion system 10, as described below, and (optionally) an electric motor (not shown) associated with a forward tunnel thruster provided at the bow of the vessel 100, which may generate a jet of water, generating a steering force, which facilitates maneuvering of the vessel 100. Likewise, the electrical energy generated by the alternator may be provided to an electric motor (not shown) associated with the rear tunnel thruster. Further, the electrical energy output by the alternator may be provided to one or more other electrical loads (not shown) of the marine vessel 100. For example, the electrical load may be a heating system, a pump, a navigation and bridge system, or other auxiliary systems on the vessel 100.

As shown in fig. 1, the flap 12 is formed in the rear of the hull 14 and projects downward from the hull 14. In some embodiments, the fins 12 may be integrally formed with the hull 14. In other embodiments, the fins 12 may be separate members secured to the hull 14 by suitable fastening means, such as by bolting or welding, to the hull 14. It will be appreciated that a plurality of wings 12 may be provided, such as two, three or four wings 12, if desired. In this case, each wing 12 houses a respective propulsion system 10. Likewise, it should also be understood that in other embodiments, the fins 12 may not be present and the propulsion system 10 may be disposed in the hull 14, or in another hull attachment, such as Google, or the like. Also in this case, a plurality of propulsion systems 10 may be provided, if desired.

It will be readily appreciated that each wing 12 may have any suitable shape that provides an interior space formed within each wing 12 that may accommodate the propulsion system 10 while providing additional buoyancy to the vessel 100. Thus, the present invention is not limited to the shape of the wing 12 shown in FIG. 1.

As also shown in fig. 1, the propulsion system 10 of the marine vessel 100 further comprises, for example, a propeller 24 of a controllable pitch propeller, a propeller shaft 22 connected to the controllable pitch propeller 24, an electric motor 26 comprising a motor shaft 28 driveably connected to the propeller shaft 22 via a first coupling 32, and a thrust bearing 30 provided separately from the electric motor 26, said thrust bearing 30 comprising a support portion 38 mounted to a suitable mounting structure arranged within the wing 12 and a hollow shaft portion 36 rotatably supported by the support portion 38. The hollow shaft portion 36 is coupled to the motor shaft 28 via the second coupling 34.

In addition, a fluid distribution unit 40 is fluidly coupled to the hollow shaft portion 36 of the thrust bearing 30 and is configured to provide a flow of hydraulic fluid, such as hydraulic oil, to control the pitch of the blades of the propeller 24 via the hollow shaft portion 36, the motor shaft 28, and the propeller shaft 22.

As shown in fig. 1, in the exemplary propulsion system 10, the propeller shaft 22, the motor shaft 28, and the hollow shaft portion 36 (i.e., the thrust bearing 30) are sequentially arranged in an in-line configuration along the axial direction L. In particular, in the example shown in fig. 1, the propeller shaft 22 and the hollow shaft portion 36 are coupled to the motor shaft 28 on opposite ends of the motor shaft 28. This means that in the exemplary propulsion system 10, the electric motor 26 is arranged between the thrust bearing 30 and the propeller shaft 28 and is coupled thereto via respective couplings 32, 34. In addition, in this example, the fluid distribution unit 40 is detachably mounted to the thrust bearing 30 on a side opposite to the side connected to the motor shaft 28 via the coupling 34.

As shown in fig. 2, the fluid distribution unit 40 includes a housing portion 54 detachably attached to the support portion 36 of the thrust bearing 30 and a rotatable portion 56 connected to the hollow shaft portion 36 of the thrust bearing 30 so as to rotate together therewith. The fluid distribution unit 40 is configured to supply hydraulic fluid to an interior space (control chamber) provided within a propeller hub 46 (see fig. 1) of the propeller 24 to actuate a corresponding actuator to change the pitch angle of the blades of the propeller 24 in a known manner. To this end, the thrust bearing 30 includes a hollow shaft portion 36, which is a rotatable member coupled to the motor shaft 28, which is also configured as a hollow shaft that includes a plurality of internal bores or conduits (not shown) for conveying hydraulic fluid. Likewise, the propeller shaft 22 also includes a corresponding plurality of hydraulic conduits (internal bores) to supply received hydraulic fluid to an internal space formed within the propeller hub 46 via the motor shaft 28. Hydraulic fluid is received from one or more hydraulic pumps by the fluid distribution unit 40 via respective conduits (not shown) and distributed to the propeller hub 46. It will be appreciated that suitable seals may be provided to obtain a fluid tight connection between the respective conduits. The details of the respective fluid supplies to adjust the pitch angle of the blades of the impeller 24 are well known to those skilled in the art and therefore will not be described in detail.

A rudder 48 forming part of the steering system of the vessel 100 is located aft of the propeller 24 and is used to steer the vessel 100 in a known manner.

The propulsion system 100 further includes a protective cover 50 mounted to the front of the propeller 24 and a rear seal 44 disposed at the front of the protective cover 50. The rear of the propeller shaft 22 is radially supported by the handle tube assembly 42, and a front seal 52 is disposed at the forward end of the handle tube assembly 42.

The propulsion system 10 also includes a shaft grounding arrangement 18 and a destruction system 16 configured to destroy the propeller shaft 22, if desired. These components and their functions are known, and thus detailed descriptions thereof will be omitted herein.

As shown in fig. 1, the electric motor 26 includes a motor housing 58 supported on corresponding mounting structures within the wing 12. Likewise, thrust bearings 30 are also mounted on corresponding mounting structures within the wing portions 12 and radially support a shaft system including the propeller shaft 22, the motor shaft 28 and the hollow shaft guard 36 while receiving axial loads acting on the shaft system. Since the thrust bearing 30 is provided separately from the electric motor 26, any suitable thrust bearing 30 may be used with any given size or configuration, depending on the application, so long as the hollow shaft portion 36 is configured to supply hydraulic fluid to the impeller 24. It will be appreciated that in some embodiments, conventional thrust bearings may be used and adjusted accordingly, for example by providing internal apertures therein to form the hollow shaft portion 36, or mounting the hollow shaft portion 36 to provide corresponding hydraulic lines or conduits. The configuration of the thrust bearings is known and one of ordinary skill in the art will readily understand how to adjust a given thrust bearing as needed to provide the hollow shaft portion 36. Likewise, those skilled in the art will readily understand how to attach, for example, a fluid distribution unit to the bearing portion 38 of the thrust bearing 30 such that its rotatable portion 56 can rotate with the hollow shaft portion 36.

At least one of the first and second couplers 32, 34 may include a respective shaft and/or a flange-to-flange connection of a coupling member provided for the shaft. For example, such a shaft-to-shaft coupling may be provided between the motor shaft 28 and the hollow shaft portion 34. Of course, one of ordinary skill in the art will readily appreciate that any suitable coupling may be used for each of the first and second couplers 32, 34. For example, at least one of the first coupling 32 and the second coupling 34 may comprise a sleeve coupling connecting the open shaft ends of the respective shafts. Such a sleeve coupling may be used, for example, as the coupling 32 between the propeller shaft 22 and the motor shaft 28. The respective couplings are known and are therefore not described in detail herein. Likewise, it will be appreciated that at least one of the first and second couplings 32, 34 may include a flexible or cushioning element disposed between the respective shafts in order to reduce vibration and the like. In the same manner, one or more disconnecting devices may be provided that disconnect at least one of the first and second couplers 32, 34. This facilitates, for example, the disconnection of the hollow shaft portion 36 from the motor shaft 28 or the disconnection of the motor shaft 28 from the propeller shaft 22. In this manner, the individual components of propulsion system 10 are more easily maintained or repaired when needed.

The electric motor 26 is a variable speed electric motor. In other embodiments, the electric motor 26 may be a constant speed electric motor. For example, the electric motor 26 may be a permanent magnet motor including a rotor integrated with the motor shaft 28 and a stator disposed, for example, radially outward of the rotor. The power rating of the electric motor 25 may be between 100 and 40000kW, preferably between 2000 and 6000 kW. Of course, it is readily understood that any type of electric motor may be used as electric motor 26, such as a DC motor, an AC motor, a synchronous or asynchronous motor, and the like. In some embodiments, a plurality of electric motors may be drivably coupled to the propeller shaft 22 in a suitable configuration of the thrust bearing 30 and the fluid distribution unit 40, e.g., in series, in the manner described above.

In some embodiments, the fluid distribution unit 40 may include a rotation sensor 60 configured to detect the rotational angle of the hollow shaft portion 36 and the propeller shaft 22. In this way, the fluid distribution unit 40 may be controlled in a suitable manner to supply hydraulic fluid to respective chambers within the propeller hub 46. Additionally, in some embodiments, one or more lubrication supply passages may be formed within the respective shaft to supply a lubricant, such as mineral oil, to the impeller hub 46.

While in the exemplary propulsion system 10 described above, the thrust bearing 30 is disposed forward of the electric motor 26 and connected to the fluid distribution unit 40 on the opposite side, in other embodiments, the thrust bearing 30 may be disposed aft of the electric motor 26. For example, the thrust bearing 30 may be arranged with its hollow shaft portion 36 connected between the propeller shaft 22 and the motor shaft 28 via the first coupling 32 and the second coupling 34, respectively. In this case, the housing portion 54 of the fluid dispensing unit 40 is detachably attached to the motor housing 58 of the electric motor 26, and the rotatable portion 56 thereof is connectable to the motor shaft 28 of the electric motor 26. The hydraulic fluid is then supplied to the impeller 24 via the motor shaft 28, the hollow shaft portion 36 and the impeller shaft 22 in this order. The other configurations are substantially the same as described above. However, it should be noted that in this configuration, for example, vibrations of the electric motor 26 may be transmitted to the fluid dispensing unit 40. If this is not desired, the previously described configuration should be used instead.

Although the marine vessel 100 is described above as an arctic vessel, it will be readily appreciated that the engine room configuration disclosed herein may be used for any other type of marine vessel, such as (multi-purpose) offshore vessels, research vessels, mail ships, ferries, military vessels, cargo vessels, fishery vessels, etc.

Additionally, although the impeller 24 is described in the illustration as a variable pitch impeller, in other embodiments the impeller 24 may be a fixed pitch impeller. It will be appreciated that the fluid dispensing unit 40 will be omitted in this case and the corresponding shaft will not be a hollow shaft. Other configurations may be the same as the above-described embodiments.

Industrial applicability

The propulsion system for the marine vessel disclosed herein is applicable to marine vessels in general to improve the repair and maintenance of its propulsion system, in particular if the propulsion system comprises an electric motor directly coupled to the propeller shaft without a gear unit.

An exemplary operation of marine vessel 100 with propulsion system 10 will be described below with reference to fig. 1 and 2.

The main engine 20 may combust a fuel such as a liquid fuel and/or a gaseous fuel to provide output power. The output power provided by the main engine 20 is converted into electric energy, and is supplied to the electric motor 26 to rotate it. Rotation of the motor shaft 28 is transferred to the propeller shaft 22 via the coupling 32, and rotation of the propeller shaft 22 rotates the propeller 24. The thrust provided by the propeller 24 may be controlled by varying the rotational speed of the electric motor 26. In addition, the thrust provided by the propellers 24 can also be controlled by varying the pitch angle of the controllable pitch propellers 24 in a suitable manner. To this end, the fluid distribution unit 40 may supply hydraulic fluid via the hollow shaft portion 36, the motor shaft 28 and the propeller shaft 22 (more particularly via respective hydraulic conduits or channels provided therein) to respective control chambers provided within the propeller 46. In this way, the desired thrust can be set by appropriate control of the pitch angle of the blades of the propeller 24.

Axial loads received through the

shafts

22, 28 and 36 are received through the thrust bearings 30. Thus, the fluid dispensing unit 40 is isolated from, for example, vibrations generated by the impeller 24 and the electric motor 26.

In the event that one or more components of propulsion system 10 are to be serviced or repaired, the respective component may be separated from the other components by, for example, disconnecting coupling 32 and/or 34. This facilitates convenient maintenance and repair of the fluid distribution unit 40, hydraulic lines provided in the respective shafts, and the like.

While the preferred embodiments of the invention have been described herein, various modifications and adaptations may be incorporated without departing from the scope of the following claims. When referring to measurable values such as parameters, amounts, time durations, and the like, terms such as "substantially", "about" or "substantially" as used herein are meant to encompass variations of ± 10% or less, preferably ± 5% or less, more preferably ± 1% or less, and more preferably ± 0.1% or less of the stated value, as long as such variations are suitable for practicing the invention. It is to be understood that the value to which the modifier "substantially" refers is itself also specifically, preferably, disclosed. The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within that range, as well as the recited endpoints.

Claims

1. A propulsion system (10) for a marine vessel (100), comprising:

a controllable pitch propeller (24);

a propeller shaft (22) connected to a controllable pitch propeller (24);

an electric motor (26) comprising a motor shaft (28) drivably connected to the propeller shaft (22) via at least a first coupling (32);

a thrust bearing (30) provided separately from the electric motor (26), the thrust bearing (30) including a support portion (38) and a hollow shaft portion (36) rotatably supported by the support portion (38), the hollow shaft portion (36) being coupled to the motor shaft (28) via a second coupling (34); and

a fluid distribution unit (4) fluidly connected to the hollow shaft portion (36) and configured to provide a flow of hydraulic fluid to the controllable pitch propeller via the hollow shaft portion (36), the motor shaft (28) and the propeller shaft (22).

2. The propulsion system of claim 1, wherein the propeller shaft (22), the motor shaft (28), and the hollow shaft portion (36) are arranged in an in-line configuration along the axial direction (L).

3. The propulsion system according to claim 1 or 2, wherein the propeller shaft (22) and the hollow shaft portion (36) are coupled to opposite ends of the motor shaft (28) via a first coupling (32) and a second coupling (34), respectively.

4. A propulsion system according to claim 3, wherein the fluid distribution unit (40) comprises a housing portion (54) detachably attached to the support portion (36) of the thrust bearing (30) and a rotatable portion (56) connected to the hollow shaft portion (36) of the thrust bearing (30).

5. A propulsion system according to claim 1 or 2, wherein a hollow shaft portion (36) is connected between the propeller shaft (22) and the motor shaft (28) and connected thereto via a first coupling (32) and a second coupling (34), respectively.

6. The propulsion system of claim 5, wherein the fluid distribution unit (40) comprises a housing portion (54) detachably attached to a motor housing (58) of the electric motor (26) and a rotatable portion (56) connected to a motor shaft (28) of the electric motor (26).

7. Propulsion system according to any of the claims 1-6, wherein at least one of the first coupling (32) and the second coupling (34) comprises a respective shaft and/or a flange-to-flange connection provided for a coupling member of the respective shaft.

8. The propulsion system according to any one of claims 1-7, wherein at least one of the first coupling (32) and the second coupling (34) comprises a sleeve coupling connecting open shaft ends of the respective shafts.

9. The propulsion system according to any one of claims 1-8, wherein at least one of the first coupling (32) and the second coupling (34) comprises a flexible element disposed between the respective shafts.

10. Propulsion system according to any of the claims 1-9, further comprising a disconnection device for disconnecting at least one of the in particular first coupling (32) and second coupling (34) to allow disconnection of the hollow shaft portion (36) from the motor shaft (28).

11. A propulsion system according to any of claims 1-10, wherein the electric motor (26) is a variable frequency electric motor, such as a permanent magnet motor, rated for between 100 and 40000kW, preferably between 2,000 and 6000 kW.

12. The propulsion system according to any one of claims 1-11, wherein the fluid distribution unit (40) comprises a rotation sensor (60) configured to detect a rotation angle of the hollow shaft portion (36).

13. The propulsion system of any one of claims 1-12, further comprising:

at least one fin (12) mounted to a rear portion of a hull (14) of the marine vessel (100), the at least one fin (12) projecting downwardly from the hull (14),

wherein the electric motor (26), the thrust bearing (30) and the fluid distribution unit (40) are arranged within the at least one wing (12).

14. A marine vessel (100) comprising:

a main engine or motor; and

the propulsion system according to any one of claims 1-13,

wherein the main engine or main motor (20) is configured to supply electrical energy to the electric motor (26) to drive the electric motor (26).

15. A marine vessel according to claim 14, wherein the marine vessel (100) is an arctic vessel, such as an arctic tender or icebreaker vessel, or an offshore vessel, a research vessel, a cruise vessel, a ferry, a military vessel or a fishery vessel.