A hybrid marine power system in which an internal combustion engine works in conjunction with an electric motor

Abstract

This invention discloses a marine hybrid power system that combines an internal combustion engine and an electric motor, comprising an electric motor (10), an internal combustion engine (20), a differential transmission assembly (30), a control unit (40), and a propeller (50). The differential transmission assembly uses a planetary gear set to achieve power distribution between the internal combustion engine and the electric motor and ensure that they rotate in opposite directions. The control unit has a built-in battery management module and a ship speed / torque sensor interface, and switches between three operating modes: pure electric drive mode: when the battery is fully charged, the electric motor drives the planetary carrier in the forward direction to drive the propeller, achieving zero-emission navigation; emergency power generation mode: when the battery charge is lower than a preset threshold, the internal combustion engine drives the planetary carrier to drive the propeller, and the excess power drives the electric motor in the reverse direction to generate electricity, achieving "recharging while sailing"; reversing power generation mode: in reverse or emergency turning situations, the internal combustion engine outputs power in reverse, the planetary gear set keeps the propeller controllable in both forward and reverse directions, and the ring gear continues to drive the electric motor in the reverse direction to generate electricity. This system has a compact structure and resolves the motor steering conflict during power generation and drive through a mechanical differential gear. It has high reliability and stability, and significantly improves the ship's safe endurance in the event of battery failure.

Description

Technical Field

[0001] This invention belongs to the field of marine propulsion technology, and in particular relates to a marine hybrid power system in which an internal combustion engine and an electric motor work together, providing a reliable emergency power generation function when the battery is depleted. Background Technology

[0002] As the electrification of ships progresses, pure electric ships are unable to meet the requirements of long-range voyages due to their limited range. Traditional hybrid power systems mostly use internal combustion engines and electric motors in parallel or series to drive the propeller, and there are few technologies that can use internal combustion engines to directly drive electric motors to generate electricity.

[0003] When a ship's battery runs out of power, the existing system needs to wait for shore power or rescue, which often leads to navigation interruption or delay and cannot provide reliable emergency power support.

[0004] Therefore, there is an urgent need for a hybrid power system that is simple in structure and can generate electricity directly from an internal combustion engine to provide emergency power for ships when the battery is depleted. Summary of the Invention

[0005] The purpose of this invention is to provide a hybrid power system that can generate electricity by directly driving an electric motor (10) from an internal combustion engine (20) when the battery is depleted, thereby providing emergency power for the ship, while also taking into account both pure electric operation and energy recovery efficiency.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: 1. A marine hybrid power system in which an internal combustion engine and an electric motor work together, comprising an electric motor (10), an internal combustion engine (20), a differential transmission assembly (30), a control unit (40), and a propeller (50). 2. The control unit (40) is configured with the following operating modes: Electric mode: When the battery has sufficient power, the electric motor (10) rotates forward and drives the propeller (50) through the differential transmission assembly for propulsion; b. Emergency power generation mode: When the battery power is lower than the preset threshold, the internal combustion engine (20) drives the electric motor (10) to reverse and generate electricity through the differential transmission component, and supplies power to the battery; c Reverse power replenishment mode: When the ship needs to reverse or make an emergency turn, the internal combustion engine (20) outputs in reverse, the planetary gear set ensures that the propeller (50) can be controlled to rotate in both directions, and the gear ring (33) maintains rotation in the opposite direction to the internal combustion engine (20), while the electric motor (10) maintains power generation.

[0007] Furthermore, the differential transmission assembly (30) includes a planetary gear set, the transmission ratio of which satisfies: ω motor : ω internal combustion engine = –k; where k is a constant of 0.5 to 2.0, and the negative sign indicates that the directions are opposite.

[0008] Furthermore, the planetary gear set includes: a sun gear (31), a planet carrier (32), and a ring gear (33), wherein the sun gear (31) is fixedly connected to the output shaft of the internal combustion engine (20), the planet carrier (32) is fixedly connected to the propeller drive shaft (50), and the ring gear (33) is connected to the electric motor (10) through a helical gear (34).

[0009] Furthermore, the control unit (40) further includes: the control unit (40) is capable of monitoring battery power, boat speed and torque status in real time.

[0010] Furthermore, in emergency power generation mode, the control unit (40) prioritizes ensuring the lowest speed of the propeller (50) to maintain the basic speed, while using the remaining power of the internal combustion engine (20) for the electric motor (10) to generate electricity, thus balancing the propulsion and power generation needs.

[0011] Compared with the prior art, the present invention, through a differential transmission assembly and control unit, enables the internal combustion engine to reverse and drive the electric motor to generate electricity when the battery is depleted, which has the following significant advantages: 1. The control unit automatically detects the battery status. In the event of insufficient battery power or power failure, the internal combustion engine drives the propeller for propulsion and converts excess mechanical energy into electric motor power generation, providing continuous power to the drive motor and key shipboard equipment to ensure uninterrupted navigation safety. 2. It can still operate in pure electric mode under non-emergency conditions to achieve zero emissions; in hybrid mode, it can fully recover residual power and improve fuel efficiency.

[0012] Through the differential transmission assembly (30) and control unit (40), the emergency power generation function of the internal combustion engine-electric motor integration is realized, which significantly improves the ship's endurance and safety assurance capabilities in the event of battery power failure. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall system structure of the present invention;

[0014] Figure 2 This is a schematic diagram of the planetary gear set structure of the present invention;

[0015] Figure 3 This is a flowchart of the invention. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Example

[0017] Please refer to Figure 1 As shown, System 100 includes an electric motor 10, an internal combustion engine 20, a differential transmission assembly 30, a propeller 50, and a control unit 40; The electric motor 10 can rotate forward to drive the propeller 50 through the differential transmission group, or it can rotate in reverse to generate electricity in emergency power generation mode. The internal combustion engine 20 is mechanically connected to the electric motor 10 and the propeller 50 via the differential transmission assembly 30; The control unit 40 has a built-in battery management module and a boat speed / torque sensor interface to monitor the battery pack status and propeller load, and switch modes according to the battery level.

[0018] Please refer to Figure 2 As shown, The differential transmission assembly 30 includes a planetary gear set, the transmission ratio of which satisfies ωmotor:ωinternal combustion engine = –k (k = 0.5~2.0); The gear set mainly consists of a sun gear 31, a planet carrier 32, and a ring gear 33. The sun gear 31 is fixedly connected to the output shaft of the internal combustion engine 20, providing the main force input to the system. The planetary carrier 32 is fixedly connected to the propeller drive shaft 50, receiving power transmitted from the sun gear to propel the ship forward; The gear ring 33 is connected to the output shaft of the motor 10 through the helical gear 34. Due to the differential speed, it rotates in opposite directions, thereby driving the motor to reverse and generate electricity.

[0019] Please refer to Figure 3 As shown, the control logic system has the following three state flows: Phase 1: Pure Electric Drive Mode When the battery has sufficient power, the control unit 40 closes the forward rotation circuit of the motor 10, and indirectly drives the planetary carrier 32 and the propeller 50 to rotate in the forward direction through the gear ring 33 in the differential assembly, so as to achieve a zero-emission propulsion condition. Phase Two: Internal Combustion Engine Driven + Electric Motor Generator (Emergency Power Generation Mode) When the battery is depleted, the control unit 40 starts the internal combustion engine 20, and the sun gear 31 inputs torque to drive the planetary carrier 32 to propel the propeller. At the same time, since the power of the internal combustion engine is greater than that required by the propeller, the difference in power is distributed to the ring gear 33 through the planetary gear set, thereby driving the electric motor 10 to reverse and generate electricity. At this point, the system achieves a state of "recharging while sailing": on the one hand, it maintains propeller propulsion, and on the other hand, it converts excess mechanical energy into electrical energy and stores it in the battery to prepare for subsequent resumption of pure electric operation. Phase 3: Reversing / Reverse Operating Conditions for Internal Combustion Engines to Charge Electricity In reverse conditions such as when the ship needs to reverse or make an emergency turn, the internal combustion engine 20 can reverse its output. The planetary gear set is designed to keep the propeller 50 able to rotate forward or backward as needed. At the same time, the gear ring 33 continues to rotate in the opposite direction to the internal combustion engine, ensuring that the electric motor 10 continues to generate electricity and supply power to the battery and power source.

[0020] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. All equivalent modifications or improvements made within the spirit and scope of the technical solutions described in the claims should be covered within the scope of protection of the present invention.

Claims

1. A marine hybrid power system in which an internal combustion engine and an electric motor work in coordination, characterized in that, include: The electric motor (10) drives the propeller (50) via the differential transmission assembly (30) or operates as a generator; An internal combustion engine (20) is mechanically connected to an electric motor (10) and a propeller (50) via a differential transmission assembly (30); The control unit (40) has a built-in battery management module and a boat speed / torque sensor interface, which is used to monitor the battery pack status and propeller load, and automatically switch between the following three modes according to the battery level: a. Pure electric drive mode: When the battery charge is higher than the preset threshold, the control unit (40) closes the forward rotation circuit of the motor (10) and indirectly drives the planetary carrier (32) and propeller (50) to rotate in the forward direction through the gear ring (33) in the differential assembly; b. Emergency power generation mode: When the battery power is lower than the preset threshold, the control unit (40) starts the internal combustion engine (20), the sun gear (31) inputs torque to the planet carrier (32) to drive the propeller (50) to propel, and the excess torque drives the motor (10) to reverse and generate electricity through the gear ring (33); c. Reversing power supply mode: In reverse working conditions such as ship reversing or emergency turning, the internal combustion engine (20) can reverse to output power, the planetary gear set ensures that the propeller (50) can be controlled to rotate in both directions, and at the same time the gear ring (33) maintains to rotate in the opposite direction to the internal combustion engine (20) to drive the electric motor (10) to generate electricity.

2. The system according to claim 1, characterized in that, The differential transmission assembly (30) includes a planetary gear set, the transmission ratio of which satisfies: ω motor : ω internal combustion engine = –k; Where k is a constant ranging from 0.5 to 2.0, and the negative sign indicates that the direction is reversed.

3. The planetary gear set according to claim 2, characterized in that, include: The sun gear (31) is fixedly connected to the output shaft of the internal combustion engine (20); Planetary carrier (32) is fixedly connected to propeller drive shaft (50); The gear ring (33) is connected to the output shaft of the motor (10) via a helical gear (34).

4. The system according to claim 1, characterized in that, In emergency power generation mode and reverse power replenishment mode, the control unit (40) prioritizes ensuring the lowest speed of the propeller (50) to maintain the basic speed, while using the excess power of the internal combustion engine (20) for the electric motor (10) to generate electricity, thus balancing the needs of propulsion and power generation.

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