Modular marine propulsion system for big vessels

Abstract

The present disclosure introduces the concept of multiple electric motors connected in parallel on the same shaft to replace the large engines in marine vessels. Each electric motor has a clutch to engage / disengage the motor from the main propulsion shaft that drives the propellers. By that, the electric motors can run on their optimum points, and when the vessels need to increase their speed, another electric motor can engage to compensated for the needed power so that the electric motors run in a high efficiency in different speeds as well as the high efficiency of the electric motors compared to internal combustion engines. The modular electric motors reduce the installation cost, maintenance cost, and emissions, as well as the risk of vessels stopping due to engine failure.

Description

[0001] MODULAR MARINE PROPULSION SYSTEM FOR BIG VESSELS

[0002] PRIORITY

[0003] The present application is related to, and claims the priority benefit of, U.S. Provisional Patent Application Serial No. 63 / 541,173, filed September 28, 2023, the contents of which are incorporated herein directly and by reference in their entirety.

[0004] BACKGROUND

[0005] Large vessels and ferries have different types of engines based on their intended application. Engines are optimized for a certain speed where they can operate with higher efficiency. Some of them are optimized in a specific economical speed like cargo vessels, while others need faster traction and maneuverability, like naval vessels. Although the introduction of electric motors provide higher levels of efficiency and power control, the use of electric motors in big vessels is limited as these vessels use big engines.

[0006] Big vessels are usually driven by one or two big internal combustion engines (ICEs). These engines are very expensive in terms of installation, operation, and maintenance. If the vessel engine fails, the ship would not be able to proceed. Having a spare engine might help to mitigate this problem but it comes with additional cost, and still having one spare engine is risky.

[0007] Having multiple small-size electric motors connected on the same shaft would help mitigate these problems as it has higher efficiency in different speeds, significantly less installation and maintenance cost, as well as the modularity approach to minimize the risk of failure. BRIEF SUMMARY

[0008] The present disclosure includes disclosure of a multiple electric motors connected on one shaft in parallel to drive a marine vessel, wherein each motor can be engaged or disengaged to and from the shaft to reduce the installation cost, maintenance cost, and emission, and reduce the risk of vessel stops due to engine failure.

[0009] The present disclosure includes disclosure of a marine propulsion system, comprising two or more electric motors connected to a motor shaft provide rotational power, the motor shaft configured to transfer rotational power from the two or more electric motors to a propulsion shaft configured to transfer the rotational power to one or more propellers configured to drive a marine vessel, a clutch configured to engage or disengage each electric motor of the two or more electric motors to and from the propulsion shaft, and a plurality of gears set to transfer the rotational power from the motor shaft to the propulsion shaft.

[0010] The present disclosure includes disclosure of a marine propulsion system, wherein each electric motor of the two or more electric motors can be engaged or disengaged to or from the propulsion shaft based on a power requirement of the marine vessel.

[0011] The present disclosure includes disclosure of a marine propulsion system, wherein the marine propulsion system runs at optimum efficiency by controlling each electric motor of the two or more electric motors to run at the optimum efficiency, and when a power demand increases or decreases, one or more electric motors of the two or more electric motors are engaged or disengaged to maintain a high operating efficiency for the propulsion system.

[0012] The present disclosure includes disclosure of a marine propulsion system, further comprising a planetary gear and a coupling in the motor shaft before the clutch to increase stability and reduce vibration which increases the efficiency of the propulsion system. The present disclosure includes disclosure of a marine propulsion system, wherein the coupling is an elastic coupling type to increase the stability and reduce the vibration which increases the efficiency of the propulsion system.

[0013] The present disclosure includes disclosure of a marine propulsion system, wherein the propulsion system may have two or more electric motors of the two or more electric motors connected to propulsion shaft based on power requirements of the marine vessel.

[0014] The present disclosure includes disclosure of a marine propulsion system, wherein the propulsion system and a second propulsion system can be used per marine vessel, whereby the propulsion system contains the two or more electric motors, and the second propulsion system contains two or more additional electric motors, each of which being connected to the propulsion shaft through the clutch.

[0015] The present disclosure includes disclosure of a marine propulsion system, wherein the electric motors can be supplied with power from one or more battery energy storage and hydrogen fuel cells.

[0016] The present disclosure includes disclosure of a marine propulsion system, wherein the hydrogen fuel cells have a hydrogen generator connected thereto to supply hydrogen to the hydrogen fuel cells.

[0017] The present disclosure includes disclosure of a marine propulsion system, further comprising an internal combustion engine connected to the propulsion shaft.

[0018] The present disclosure includes disclosure of a marine propulsion system, wherein the at least two electric motors are optimized to run at certain speeds and the internal combustion engine is optimized to run on other speed levels. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The disclosed embodiments and other features, advantages, and disclosures contained herein, and the matter of attaining them, will become apparent and the present disclosure will be better understood by reference to the following description of the present disclosure taken in conjunction with the accompanying drawings, wherein:

[0020] Fig. 1 illustrates a top view of an embodiment of a modular marine propulsion system according to an exemplary embodiment of the present disclosure.

[0021] Fig. 2 illustrates a top view of an embodiment of a modular marine propulsion system having six electric motors according to an exemplary embodiment of the present disclosure.

[0022] Fig. 3 illustrates a top view of an embodiment of two modular marine propulsion systems according to an exemplary embodiment of the present disclosure.

[0023] Fig. 4 illustrates a top view of an embodiment of a modular marine propulsion system having battery energy storage system, hydrogen fuel cell storage system and a hydrogen generator according to an exemplary embodiment of the present disclosure.

[0024] Fig. 5 illustrates a top view of an embodiment of a modular marine propulsion system having a combination of electric motors and internal combustion engines according to an exemplary embodiment of the present disclosure.

[0025] As such, an overview of the features, functions and / or configurations of the components depicted in the figures will now be presented. It should be appreciated that not all of the features of the components of the figures are necessarily described and some of these non-discussed features (as well as discussed features) are inherent from the figures themselves. Other non-discussed features may be inherent in component geometry and / or configuration. Furthermore, wherever feasible and convenient, like reference numerals are used in the figures and the description to refer to the same or like parts or steps. The figures are in a simplified form and not to precise scale. DETAILED DESCRIPTION

[0026] For the purposes of promoting an understanding the principles of the present disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of this disclosure is thereby intended.

[0027] Marine vessels are widely used in shipping, transportation, and border control. They are usually driven by one or two engines. These engines are large internal combustion engines (ICEs) configured to supply the needed power to drive the large vessel. Each engine is designed to run at a specific speed where it can give its optimum efficiency while the efficiency significantly reduced in other speeds. Moreover, these engines need to be available all the time as the vessel would not work / propel if the engine is malfunctioning. Although some vessels have a spare engine, the risk of engine failure still exists. In addition, the cost of maintenance / replacement of each engine is significantly high. The present disclosure introduces the concept of using multiple electric motors connected in parallel on the same shaft to replace the large engines in marine vessels. Each electric motor has a clutch to engage / disengage the motor from the main shaft that drives the propellers. By that, the electric motors can each run on their optimum point, and when the vessel needs to increase its speed, another motor can engage to compensate for the needed power so that the electric motors continue to run at high efficiency in different speeds as well as the high efficiency of the electric motors compared to ICE engines.

[0028] The present disclosure includes disclosure of marine propulsion system 100 that comprises multiple electric motors 101 to provide rotational power to drive a vessel 200, a motor shaft 110 that is configured to transfer the rotational power from the motors 101 to a clutch 104, the clutch 104 configured to engage / disengage each motor 101 to the propulsion system 100. Multiple gears 105 are used to connect the clutch 104 to the propulsion shaft 106 which is in turn connected to the propellers 107 to drive the vessel 200. The electric motors 101 provide the rotational power to the vessel 200, and with the help of the clutch 104, the electric motors 101 can be engaged to or disengaged from the propulsion shaft 106 through a set of gears 105. The propulsion shaft 106 transfers the rotational movement from each engaged motor 101 to one or more propellers 107, such as shown in Fig. 1.

[0029] Using multiple electric motors 101 instead of one big engine has several advantages such as a high efficiency in multiple speed ranges where the user can engage / disengage the required number of electric motors 101 based on the speed or the required torque, while other electric motors 101 remain idle to optimize the propulsion system 100 efficiency. The marine propulsion system 100 runs at optimum efficiency by controlling each electric motor 101 to run at its optimum efficiency, and when the power demand increases or reduces, the one or more electric motors 101 are engaged or disengaged using the clutch 104 to maintain a high operating efficiency for the propulsion system 100. Also, having multiple electric motors 101 reduces the chances of motor 101 failures. If one motor 101 fails, the vessels 200 can continue to run in a reduced performance while a failure in the large ICE engine might lead to the vessel’s 200 propulsion failure. In addition, having one or more spare electric motors 101 is significantly cheaper than having a spare large ICE engine. In terms of cost, having few electric motors 101 are much cheaper in installation, operation, and maintenance compared to one large ICE engine.

[0030] In at least one embodiment of the present disclosure, the electric motor 101 might be connected to a planetary gear 102 and a coupling 103 (for example an elastic coupling) in the motor shaft 110 before the clutch 104 to increase the stability and reduce the vibration which increase the efficiency of the propulsion system 100, such as shown in Fig. 1

[0031] In at least one embodiment of the present disclosure, the propulsion system 100 can control the engagement / disengagement of each electric motor 101 based on the power demand. When the power demand increases to a level causing the current engaged electric motors 101 to work beyond their optimum efficiency levels, the propulsion system 100 engages another electric motor 101 to maintain the optimum efficiency levels. On the other hand, when the power demand decreases, the propulsion system 100 can disengage one or more of the electric motors 101 to avoid running the motors 101 at low efficiency levels.

[0032] In at least one embodiment of the present disclosure, the propulsion system 100 may have two or more electric motors 101 connected to the propulsion shaft 106 based on the power requirements of the marine vessel 200, such as shown in Fig. 2 where six electric motors 101 are connected to the propulsion shaft 106.

[0033] In at least one embodiment of the present disclosure, the marine vessel 200 may have one or more propulsion systems 100 where each one of them contains a set of electric motors 101 connected to the propulsion shaft 106 through a clutch 104, such as shown in Fig. 3.

[0034] In at least one embodiment of the present disclosure, the electric motor 101 can be supplied from multiple energy storage systems such as battery energy storage 108 and / or hydrogen fuel cells 109, such as shown in Fig. 4. In addition, a hydrogen fuel cell 109 may have a hydrogen generator 109a connected to it to supply hydrogen to the fuel cell 109, such as shown in Fig. 4.

[0035] In at least one embodiment of the present disclosure, the propulsion system 100 may have a combination of electric motors 101 and ICE engines 111 connected to the propulsion shaft 106 where the electric motors 101 are optimized to run on a certain speed and the ICE engines 111 optimized to run on other speed levels, such as shown in Fig. 5.

[0036] While various embodiments of devices and systems and methods for using the same have been described in considerable detail herein, the embodiments are merely offered as non-limiting examples of the disclosure described herein. It will therefore be understood that various changes and modifications may be made, and equivalents may be substituted for elements thereof, without departing from the scope of the present disclosure. The present disclosure is not intended to be exhaustive or limiting with respect to the content thereof.

[0037] Further, in describing representative embodiments, the present disclosure may have presented a method and / or a process as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth therein, the method or process should not be limited to the particular sequence of steps described, as other sequences of steps may be possible. Therefore, the particular order of the steps disclosed herein should not be construed as limitations of the present disclosure. In addition, disclosure directed to a method and / or process should not be limited to the performance of their steps in the order written. Such sequences may be varied and still remain within the scope of the present disclosure.

Claims

CLAIMS1. A marine propulsion system, comprising: two or more electric motors connected to a motor shaft configured to provide and transfer rotational power from the two or more electric motors to a propulsion shaft configured to transfer the rotational power to one or more propellers configured to drive a marine vessel; a clutch configured to engage or disengage each electric motor of the two or more electric motors to and from the propulsion shaft; and a plurality of gears set to transfer the rotational power from the motor shaft to the propulsion shaft.

2. The marine propulsion system of claim 1, wherein each electric motor of the two or more electric motors can be engaged or disengaged to or from the propulsion shaft based on a power requirement of the marine vessel.

3. The marine propulsion system of claim 1, wherein the marine propulsion system runs at optimum efficiency by controlling each electric motor of the two or more electric motors to run at the optimum efficiency, and when a power demand increases or decreases, one or more electric motors of the two or more electric motors are engaged or disengaged to maintain a high operating efficiency for the propulsion system.

4. The marine propulsion system of claim 1, further comprising: a planetary gear and a coupling in the motor shaft before the clutch to increase stability and reduce vibration which increases the efficiency of the propulsion system.

5. The marine propulsion system of claim 4, wherein the coupling is an elastic coupling type to increase the stability and reduce the vibration which increases the efficiency of the propulsion system.

6. The marine propulsion system of claim 1, wherein the propulsion system may have two or more electric motors of the two or more electric motors connected to propulsion shaft based on power requirements of the marine vessel.

7. The marine propulsion system of claim 1, wherein the propulsion system and a second propulsion system can be used per marine vessel, whereby the propulsion system contains the two or more electric motors and the second propulsion system contains two or more additional electric motors, each of which being connected to the propulsion shaft through the clutch.

8. The marine propulsion system of claim 1, wherein the electric motors can be supplied with power from one or more of battery energy storage and hydrogen fuel cells.

9. The marine propulsion system of claim 8, wherein the hydrogen fuel cells have a hydrogen generator connected thereto to supply hydrogen to the hydrogen fuel cells.

10. The marine propulsion system of claim 1, further comprising: an internal combustion engine connected to the propulsion shaft.

11. The marine propulsion system of claim 10, wherein the at least two electric motors are optimized to run at certain speeds and the internal combustion engine is optimized to run on other speed levels.

12. A marine propulsion system, comprising: two or more electric motors connected to a motor shaft provide rotational power, the motor shaft configured to transfer rotational power from the two or more electric motors to a propulsion shaft configured to transfer the rotational power to one or more propellers configured to drive a marine vessel; a clutch configured to engage or disengage each electric motor of the two or more electric motors to and from the propulsion shaft; and a plurality of gears set to transfer the rotational power from the motor shaft to the propulsion shaft; wherein each electric motor of the two or more electric motors can be engaged or disengaged to or from the propulsion shaft based on a power requirement of the marine vessel; andwherein the propulsion system may have two or more electric motors of the two or more electric motors connected to propulsion shaft based on power requirements of the marine vessel.

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