阅读说明：本技术 一种供无人水下航行器搭载的海洋温差能相变发电装置 (Ocean temperature difference energy phase change power generation device for unmanned underwater vehicle ) 是由 杨亚楠 李博 王树新 *** 刘崇义 于 2020-05-25 设计创作，主要内容包括：本发明公开一种供无人水下航行器搭载的海洋温差能相变发电装置,由海洋温差能俘获装置和能量转换装置两部分组成,海洋温差能俘获装置和能量转换装置之间通过第一液压钢管相连通；海洋温差能俘获装置内部通过轴向移动的活塞隔离液压油与相变材料；能量转换装置的耐压封闭腔由前盖、皮囊、油舱、前舱、肋环、后舱、后盖依次连接组成；能量转换装置的内部设有相互连接的液压系统和发电储能系统,液压系统包括油舱、蓄能器、过滤器、电磁阀、压力传感器、液压马达、液压马达转换接头、第一单向阀、节流阀和第二单向阀；发电储能系统由电池组支架、电路板、锂电池组、电路板支架、弹性联轴器、齿轮增速机、发电机组成。(The invention discloses an ocean temperature difference energy phase change power generation device carried by an unmanned underwater vehicle, which consists of an ocean temperature difference energy capturing device and an energy conversion device, wherein the ocean temperature difference energy capturing device and the energy conversion device are communicated through a first hydraulic steel pipe; hydraulic oil and a phase change material are isolated from the inside of the ocean temperature difference energy capture device through an axially moving piston; the pressure-resistant closed cavity of the energy conversion device is formed by sequentially connecting a front cover, a leather bag, an oil tank, a front cabin, a ribbed ring, a rear cabin and a rear cover; the hydraulic system comprises an oil tank, an energy accumulator, a filter, an electromagnetic valve, a pressure sensor, a hydraulic motor adapter, a first check valve, a throttle valve and a second check valve; the power generation and energy storage system is composed of a battery pack support, a circuit board, a lithium battery pack, a circuit board support, an elastic coupling, a gear speed increaser and a power generator.)

1. An ocean temperature difference energy phase change power generation device carried by an unmanned underwater vehicle is carried outside a body of the unmanned underwater vehicle (51), is connected and fixed, can perform submerged motion underwater along with the unmanned underwater vehicle (51) and realizes collection and conversion of ocean temperature difference energy into electric energy required by the vehicle, and is characterized by comprising an ocean temperature difference energy capturing device (48) and an energy conversion device (49), wherein the ocean temperature difference energy capturing device (48) is communicated with the energy conversion device (49) through a first hydraulic steel pipe (50); the ocean temperature difference energy capture device (48) is internally isolated from the hydraulic oil and the phase change material through an axially moving piston (33); the pressure-resistant closed cavity of the energy conversion device (49) is formed by sequentially connecting a front cover (1), a leather bag (2), an oil tank (3), a front cabin (4), a rib ring (5), a rear cabin (7) and a rear cover (9); a hydraulic system and a power generation and energy storage system which are connected with each other are arranged in the energy conversion device (49), and the hydraulic system comprises an oil tank (3), an energy accumulator (6), a filter (13), an electromagnetic valve (16), a pressure sensor (22), a hydraulic motor (26), a hydraulic motor conversion joint (27), a first check valve (35), a throttle valve (36) and a second check valve (37); the power generation and energy storage system consists of a battery pack support (8), a circuit board (17), a lithium battery pack (19), a circuit board support (20), an elastic coupling (28), a gear speed increaser (30) and a generator (31);

the hydraulic system comprises three functional oil paths, namely an energy storage oil path, an energy release power generation oil path and an oil return oil path; the energy storage oil path is formed by sequentially connecting an ocean temperature difference energy capturing device (48), a first hydraulic steel pipe (50), a first one-way valve (35), a rib ring (5) and an energy accumulator (6); the energy-releasing power generation oil way is formed by sequentially connecting an energy accumulator (6), a rib ring (5), a throttle valve (36), an electromagnetic valve (16), a second hydraulic steel pipe (14), a filter (13), a third hydraulic steel pipe (12), a hydraulic motor (26), a hydraulic motor adapter (27), a fourth hydraulic steel pipe (25), a fifth hydraulic steel pipe (23), a sixth hydraulic steel pipe (24), an oil cabin (3) and a leather bag (2); the return oil path is formed by sequentially connecting a leather bag (2), an oil cabin (3), a sixth hydraulic steel pipe (24), a second one-way valve (37), a rib ring (5), a first hydraulic steel pipe (50) and an ocean temperature difference energy capturing device (48).

2. The marine temperature difference energy phase change power generation device for the unmanned underwater vehicle to carry out according to claim 1, wherein the oil tank (3), the front tank (4) and the rib ring (5) of the pressure-resistant closed cavity are axially locked by a long pull rod (11), the rib ring (5) and the rear tank (7) are axially locked by a short pull rod (21), and the long pull rod (11) and the short pull rod (21) are fastened by nuts; the front cover (1), the leather bag (2) and the oil cabin (3) form an inner oil cavity of the hydraulic system, and a plug (32) is arranged at the bottom of the oil cabin (3) to prevent hydraulic oil from leaking to the front cabin (4); grooves are formed in the outer circular surfaces of the front cover (1), the rib ring (5) and the rear cover (9), and a sealing ring (38) is installed in the grooves to realize axial sealing; threaded holes are uniformly distributed in the circumferential direction at the two ends of the pressure-resistant closed cavity and used for fastening the front cover (1) at the port of the oil tank (3) and fastening the rear cover (9) at the port of the rear tank (7).

3. The marine temperature difference energy phase change power generation device carried by the unmanned underwater vehicle as claimed in claim 1, wherein a gear speed increaser (30) of the power generation and energy storage system is connected with a hydraulic motor (26) through an elastic coupling (28); the generator (31) and the gear speed increaser (30) are coaxially and fixedly connected to a support frame (29), the support frame (29) is fixedly connected to the tail end of a support base plate (15), and the root of the support base plate (15) is fastened with a rib ring (5); the circuit board support (20), the circuit board (17) and the battery pack support (8) are sequentially connected and installed on the bosses on the inner side of the rear cover (9) layer by layer through bolts; the circuit board (17) is provided with a rectification filtering voltage stabilizing circuit (34) which can convert alternating current generated by the generator (31) into stable direct current to charge the lithium battery pack (19).

4. The ocean temperature difference energy phase change power generation device for the unmanned underwater vehicle to carry according to claim 1, wherein the rib ring (5) is provided with a first threaded hole (40), a first oil hole (41), a second threaded hole (43), a third threaded hole (44) and a fourth threaded hole (45); the first threaded hole (40), the first oil hole (41), the second threaded hole (43), the third threaded hole (44) and the fourth threaded hole (45) are communicated through a first oil path (42);

the first check valve (35) is arranged in the first oil way (42), and the first check valve (35) is used for preventing hydraulic oil in the energy accumulator (6) from reversely flowing into the ocean temperature difference energy capturing device (48); the second check valve (37) is arranged in the fourth threaded hole (45) and is used for preventing hydraulic oil in the ocean temperature difference energy capturing device (48) from reversely flowing into the oil tank (3); the throttle valve (36) is arranged in the second threaded hole (43) and is used for adjusting the flow of hydraulic oil of the energy-releasing power generation oil way; the pressure sensor (22) is arranged in the third threaded hole (44) and is used for detecting the energy storage pressure of the energy accumulator (6);

the first threaded hole (40) is communicated with the first oil hole (41), so that the ocean temperature difference energy capture device (48) can inject oil into the energy accumulator (6) through an energy accumulation oil path; the first oil hole (41) is communicated with the second threaded hole (43), so that the oil is filled into the oil tank (3) by the energy-releasing power generation oil way through the energy accumulator (6), and the hydraulic motor (26) is driven to rotate; the first threaded hole (40) is communicated with the fourth threaded hole (45), so that the oil tank (3) is filled with oil to the ocean temperature difference energy capture device (48) through an oil return oil way.

5. The ocean temperature difference energy phase change power generation device carried by the unmanned underwater vehicle as claimed in claim 1, wherein the electromagnetic valve (16) is a two-position two-way normally closed electromagnetic valve, and in the energy release power generation oil path, the electromagnetic valve (16) is electrified to conduct the oil path between the energy accumulator (6) and the oil tank (3); when the electromagnetic valve (16) is powered off, the energy releasing and generating oil way is interrupted, and the energy storage oil way works.

6. The ocean temperature difference energy phase change power generation device for the unmanned underwater vehicle to carry according to claim 1, wherein the end surface of the rear cover (9) is provided with a threaded hole and is provided with a watertight cabin penetrating piece (18); the watertight bulkhead (18) is connected as an electrical interface to the unmanned underwater vehicle (51).

7. The ocean temperature difference energy phase change power generation device for the unmanned underwater vehicle to carry according to claim 2, wherein an interface of the leather bag (2) is installed at a central counter bore of the oil tank (3) and is buckled and fixed by a leather bag installation flange (10); a groove is formed at the interface of the leather bag (2), and axial sealing is realized through a sealing ring (47), so that gas in the leather bag (2) is prevented from entering the oil tank (3); the leather bag (2) is pre-filled with air with the air pressure of 1bar when being initially installed.

Technical Field

The invention belongs to the technical field of underwater unmanned vehicle engineering, and particularly relates to a compact and modularized ocean temperature difference energy phase change power generation device which is carried and used for small and medium-sized unmanned underwater vehicles.

Background

At present, unmanned underwater vehicles mainly rely on batteries carried by the unmanned underwater vehicles to provide energy for electric devices carried by the unmanned underwater vehicles. However, the endurance and self-sustaining capability of the unmanned underwater vehicle are greatly restricted due to the limited energy of the carried battery. With the continuous development of ocean observation and detection tasks towards the deep sea direction, the research on the related technology for improving the endurance and the self-sustaining capability of the unmanned underwater vehicle is increasingly concerned.

The method for obtaining electric energy supplement by using the in-situ marine environment energy is a potential technical approach for solving the problem of insufficient energy supply of the unmanned underwater vehicle and improving endurance and self-sustaining capability. The current marine environmental energy sources which can be used for generating electricity comprise various forms of marine temperature difference energy, wave energy and the like. The ocean temperature difference energy refers to heat energy existing between surface layer warm water and deep layer cold water of the ocean due to temperature difference, and has the potential of providing stable and continuous energy supply for the unmanned underwater vehicle due to the characteristics of strong stability, small day and night fluctuation, no influence of sea condition factors and slight seasonal change.

According to the ocean temperature difference energy phase change power generation technology, ocean temperature difference energy is captured and converted into hydraulic energy by the aid of periodic thermal expansion and cold contraction characteristics of solid-liquid phase change materials through reciprocating crossing of equipment between a seawater cold layer and a seawater cold layer, and electric energy is obtained through a power generation component. Based on the ocean temperature difference energy phase change power generation technology, SOLO-TREC temperature difference power generation section buoys and SLOCUM E-TWIN temperature difference power generation underwater gliders are successively introduced, however, the devices adopt the technical scheme of integrating the aircraft body and the temperature difference energy phase change power generation system, the aircraft system is numerous and complicated, the temperature difference energy phase change power generation system obviously changes the layout structure of other subsystems of the aircraft, the research and development technical difficulty is increased, the research and development cost and the period are increased, the reliability of a prototype is poor, the performance still needs to be improved, and the technical maturity difference is obvious compared with the similar aircraft powered by a battery.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, and solves the problems of great research and development technical difficulty, complex system, high research and development cost and low technical maturity of an ocean temperature difference energy phase change power generation aircraft; the invention provides an ocean temperature difference energy phase change power generation device carried by an unmanned underwater vehicle, which can be used as an independent modularized temperature difference energy phase change power generation device to be carried by a mature existing underwater vehicle platform in an external mode, and obtains electric energy used by electric devices of the vehicle by utilizing an ocean temperature difference environment in the process of submerging and surfacing along with the underwater vehicle.

The purpose of the invention is realized by the following technical scheme:

an ocean temperature difference energy phase change power generation device carried by an unmanned underwater vehicle is carried outside an unmanned underwater vehicle body, is connected and fixed, can perform submerged floating motion underwater along with the unmanned underwater vehicle and realize collection and conversion of ocean temperature difference energy into electric energy required by the vehicle, and consists of an ocean temperature difference energy capturing device and an energy conversion device, wherein the ocean temperature difference energy capturing device and the energy conversion device are communicated through a first hydraulic steel pipe; hydraulic oil and a phase change material are isolated from the inside of the ocean temperature difference energy capture device through an axially moving piston; the pressure-resistant closed cavity of the energy conversion device is formed by sequentially connecting a front cover, a leather bag, an oil tank, a front cabin, a rib ring, a rear cabin and a rear cover; the energy conversion device is internally provided with a hydraulic system and a power generation and energy storage system which are connected with each other, wherein the hydraulic system comprises an oil tank, an energy accumulator, a filter, an electromagnetic valve, a pressure sensor, a hydraulic motor conversion joint, a first one-way valve, a throttle valve and a second one-way valve; the power generation and energy storage system consists of a battery pack support, a circuit board, a lithium battery pack, a circuit board support, an elastic coupling, a gear speed increaser and a power generator;

the hydraulic system comprises three functional oil paths, namely an energy storage oil path, an energy release power generation oil path and an oil return oil path; the energy storage oil path is formed by sequentially connecting an ocean temperature difference energy capturing device, a first hydraulic steel pipe, a first one-way valve, a rib ring and an energy accumulator; the energy-releasing power generation oil way is formed by sequentially connecting an energy accumulator, a rib ring, a throttle valve, an electromagnetic valve, a second hydraulic steel pipe, a filter, a third hydraulic steel pipe, a hydraulic motor adapter, a fourth hydraulic steel pipe, a fifth hydraulic steel pipe, a sixth hydraulic steel pipe, an oil cabin and a leather bag; the oil return oil way is formed by sequentially connecting a leather bag, an oil cabin, a sixth hydraulic steel pipe, a second one-way valve, a rib ring, a first hydraulic steel pipe and an ocean temperature difference energy capturing device.

Furthermore, the oil cabin, the front cabin and the rib ring of the pressure-resistant closed cavity are axially locked by a long pull rod, the rib ring and the rear cabin are axially locked by a short pull rod, and the long pull rod and the short pull rod are fastened by nuts; the front cover, the leather bag and the oil cabin form an inner oil cavity of the hydraulic system, and a plug is arranged at the bottom of the oil cabin to prevent hydraulic oil from leaking to the front cabin; grooves are formed in the outer circular surfaces of the front cover, the rib ring and the rear cover, and sealing rings are installed in the grooves to realize axial sealing; and threaded holes are uniformly distributed in the circumference of the two ends of the pressure-resistant closed cavity and used for fastening the front cover at the port of the oil tank and fastening the rear cover at the port of the rear tank.

Furthermore, a gear speed increaser of the power generation and energy storage system is connected with the hydraulic motor through an elastic coupling; the generator and the gear speed increaser are coaxially and fixedly connected to a support frame, the support frame is fixedly connected to the tail end of a support base plate, and the root of the support base plate is fastened with a rib ring; the circuit board bracket, the circuit board and the battery pack bracket are sequentially connected and installed on the boss on the inner side of the rear cover layer by layer through bolts; the circuit board is provided with a rectifying, filtering and voltage stabilizing circuit which can convert alternating current generated by the generator into stable direct current to charge the lithium battery pack.

Furthermore, a first threaded hole, a first oil hole, a second threaded hole, a third threaded hole and a fourth threaded hole are formed in the rib ring; the first threaded hole, the first oil hole, the second threaded hole, the third threaded hole and the fourth threaded hole are communicated through a first oil path;

the first check valve is arranged in the first oil way and used for preventing hydraulic oil in the energy accumulator from reversely flowing into the ocean temperature difference energy capturing device; the second one-way valve is arranged in the fourth threaded hole and used for preventing hydraulic oil in the ocean temperature difference energy capturing device from reversely flowing into the oil cabin; the throttle valve is arranged in the second threaded hole and used for adjusting the flow of hydraulic oil of the energy-releasing power generation oil way; the pressure sensor is arranged in the third threaded hole and used for detecting the energy storage pressure of the energy accumulator;

the first threaded hole is communicated with the first oil hole, so that the ocean temperature difference energy capture device can fill oil into the energy accumulator through the energy storage oil way; the first oil hole is communicated with the second threaded hole, so that the oil is filled into the oil tank by the energy-releasing power generation oil way through the energy accumulator, and the hydraulic motor is driven to rotate; the first threaded hole is communicated with the fourth threaded hole, so that the oil tank can be filled with oil to the ocean temperature difference energy capture device through an oil return oil way.

Furthermore, the electromagnetic valve is a two-position two-way normally closed electromagnetic valve, and in the energy release power generation oil way, the electromagnetic valve is electrified to conduct an oil way between the energy accumulator and the oil tank; when the electromagnetic valve is powered off, the energy releasing and generating oil way is interrupted, and the energy storing oil way works.

Furthermore, the end face of the rear cover is provided with a threaded hole, and a watertight cabin penetrating piece is installed; the watertight penetration piece is used as an electrical interface to be connected with the unmanned underwater vehicle.

Furthermore, the leather bag interface is arranged at a central counter bore of the oil tank and is buckled and fixed by a leather bag mounting flange; a groove is formed at the interface of the leather bag, and axial sealing is realized through a sealing ring, so that gas in the leather bag is prevented from entering the oil tank; the bladder was initially filled with air at 1bar pressure during installation.

The cycle process of the submerging and surfacing motion of the unmanned underwater vehicle comprises three stages: a submergence preparation stage, a submergence stage and a floating stage. In these three phases, the three hydraulic circuits of the hydraulic system of the invention work in stages:

in the submergence preparation stage, the unmanned underwater vehicle initially floats on the water surface, and the ocean temperature difference energy capturing device is soaked in surface layer warm seawater. At this stage, the phase-change material in the ocean temperature difference energy capture device is in a liquid state, the oil cabin is filled with hydraulic oil, the leather bag is in a compressed state under the extrusion action of the hydraulic oil, and the pressure is greater than 1 bar.

In the submergence stage, the temperature is gradually reduced along with the increasing submergence depth of the unmanned underwater vehicle. When the water temperature is lower than the melting point of the phase-change material, the phase-change material begins to gradually solidify and contract, meanwhile, under the action of the air pressure of the leather bag, the oil return oil way begins to work, hydraulic oil sequentially passes through the sixth hydraulic steel pipe, the second one-way valve, the rib ring and the first hydraulic steel pipe from the oil tank and is injected into the ocean temperature difference energy capturing device, and the hydraulic oil in the ocean temperature difference energy capturing device pushes the sealing piston to move towards the phase-change material side.

In the floating stage, the unmanned underwater vehicle gradually rises, and the water temperature gradually rises. When the water temperature is higher than the melting point of the phase-change material, the phase-change material begins to gradually melt and expand, the phase-change material pushes the sealing piston to move towards the hydraulic oil side in the ocean temperature difference energy capturing device, the energy storage oil way begins to work, and the hydraulic oil is injected into the energy storage device from the ocean temperature difference energy capturing device through the first hydraulic steel pipe, the first check valve and the rib ring in sequence. In the process, the ocean temperature difference energy is converted into hydraulic potential energy, and the pressure of the energy accumulator is detected through the pressure sensor.

When the pressure of the energy accumulator reaches a set value, the energy-releasing power generation oil way starts to work, the electromagnetic valve is opened, and high-pressure oil in the energy accumulator sequentially passes through the rib ring, the throttle valve, the electromagnetic valve, the second hydraulic steel pipe, the filter, the third hydraulic steel pipe, the hydraulic motor adapter, the fourth hydraulic steel pipe, the fifth hydraulic steel pipe and the sixth hydraulic steel pipe and is injected into the oil tank. In the process, the hydraulic motor is driven to rotate by high-pressure oil, and the output torque of the hydraulic motor drives the generator to rotate and generate electricity through the elastic coupling and the gear speed increaser; the current is converted and transmitted to the lithium battery pack through the rectifying, filtering and voltage stabilizing circuit on the circuit board. When the accumulator pressure drops to zero, the solenoid valve closes. And then the energy accumulator can continue to charge energy and release energy to generate electricity until the phase change material is completely melted.

And after the unmanned underwater vehicle returns to the sea surface, completing a complete cycle and preparing for the next cycle. The electric energy stored in the lithium battery pack can be supplied to electric devices of the unmanned underwater vehicle for use through the watertight penetration piece.

Compared with the prior art, the technical scheme of the invention has the following beneficial effects:

1. the ocean thermal energy capturing device comprises three columnar shape components, comprises two ocean thermal energy capturing devices and an energy conversion device, has the characteristics of large length-diameter ratio and 70mm of the outer diameter of the ocean thermal energy capturing device and 160mm of the outer diameter of the energy conversion device, and is suitable for being carried to an unmanned underwater vehicle in the shape of a torpedo body along the axial direction. The design mode does not need to greatly change the structure of the original underwater vehicle, and can furthest reduce the influence on the hydrodynamic characteristics of the underwater vehicle.

2. The ocean temperature difference energy capturing device and the energy conversion device are integrated together to be an independent functional module, and the ocean temperature difference energy capturing device and the energy conversion device can be electrically connected with the existing mature unmanned underwater vehicle through the electrical interface, so that the ocean temperature difference energy capturing device has universality. Can be carried on the prior art-mature underwater glider platform and the profile buoy platform for energy supplement. The invention avoids the change of the internal structure of the underwater vehicle, and reduces the technical complexity, the research and development period and the research and development cost of research and development.

3. According to the invention, a design scheme of sharing valves is adopted, and a hydraulic oil way is arranged in the rib ring, so that the conduction function of the hydraulic oil way is combined with the cabin body connection function of the rib ring; meanwhile, the plug-in throttle valve and the check valve are installed in the oil way, the common design of the valve parts is realized, the occupied space of the hydraulic oil way in the pressure-resistant closed cavity is obviously reduced, the compactness of the energy conversion device is improved, and the compactness and the miniaturization design are realized.

4. The invention adopts the scheme that the lithium battery pack stores electric energy obtained by ocean temperature difference energy and further supplies power to the electric device of the underwater vehicle by the lithium battery pack. According to the scheme, the waste of the generating energy caused by the fact that the instantaneous generating capacity of the temperature difference energy phase change generating set is inconsistent with the instantaneous power consumption of the underwater vehicle is avoided, the lithium battery pack achieves the effect of 'peak clipping and valley filling', and the effective utilization rate of the generating energy is improved.

5. The invention adds a gear speed increaser between a hydraulic motor and a generator. The gear speed increaser completes speed increasing and torque reducing conversion on the output shaft of the hydraulic motor, realizes matching of the rotating speed and the torque of the hydraulic motor and the generator, realizes simultaneous operation of the hydraulic motor and the generator in a high-efficiency interval, and improves the energy conversion efficiency in the power generation process.

6. Compared with piston and leather bag type energy accumulators with equal volumes, the diaphragm type energy accumulator has high energy storage pressure, light weight and small volume, reduces the occupied space in a pressure-resistant closed cavity, can reduce the dead weight of the device and realizes light weight.

7. The energy conversion device cabin body realizes the fastening of the oil cabin, the front cabin, the rib ring and the rear cabin by a plurality of sections of pull rods. Under the marine navigation conditions of long-term violent and large-amplitude vibration, the pull rod fastening scheme has the advantages of durability, high reliability and difficulty in loosening.

Drawings

FIG. 1 is a schematic view of the present invention carried on an unmanned underwater vehicle;

FIGS. 2a and 2b are schematic structural views of an energy conversion device;

FIG. 3 is a hydraulic schematic of the present invention;

FIG. 4 is a schematic diagram of a pressure-resistant closed cavity locking structure of the energy conversion device;

FIGS. 5a to 5c are schematic views of rib rings and valve members;

FIG. 6 is a schematic view of a structure for fixedly connecting a bladder interface and an oil tank;

FIGS. 7a to 7d are schematic views of four processes for generating electricity according to the present invention;

fig. 8 is a schematic view of the invention submerged with an unmanned underwater vehicle.

Detailed Description

The invention is described in further detail below with reference to the figures and specific examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in FIG. 1, the invention provides a compact and modular ocean temperature difference energy phase change power generation device which is carried and used for a small and medium-sized unmanned underwater vehicle 51, and mainly comprises an ocean temperature difference energy capture device 48 and an energy conversion device 49. The invention is arranged outside the unmanned underwater vehicle 51 body and is connected and fixed, as shown in figure 1; and can perform submerging and surfacing movement with the unmanned underwater vehicle 51 and realize collection and conversion of ocean temperature difference energy into electric energy required by the vehicle, as shown in fig. 7.

As shown in fig. 2a and 2b, the energy conversion device 49 is composed of a pressure-resistant closed cavity, a hydraulic system and a power generation and energy storage system. The pressure-resistant closed cavity consists of a front cover 1, a leather bag 2, an oil tank 3, a front cabin 4, a rib ring 5, a rear cabin 7 and a rear cover 9; the hydraulic system consists of an oil tank 3, an energy accumulator 6, a filter 13, an electromagnetic valve 16, a pressure sensor 22, a hydraulic motor 26, a hydraulic motor conversion joint 27, a one-way valve 35, a throttle valve 36, a one-way valve 37 and hydraulic steel pipes and joints among all hydraulic components; the power generation and energy storage system is composed of a battery pack support 8, a circuit board 17, a lithium battery pack 19, a circuit board support 20, an elastic coupling 28, a gear speed increaser 30 and a generator 31. As shown in FIG. 3, the ocean thermal energy capture device 48 contains hydraulic oil and phase change material therein and is separated by an axially movable sealing piston 33.

As shown in fig. 2a and 2b, the front cover 1, the bladder 2 and the oil tank 3 constitute an inner oil chamber of the hydraulic system. The end face of the rear cover 9 is designed with a threaded hole and is provided with a watertight cabin penetrating piece 18. The watertight bulkhead 18 is the electrical interface of the present invention and is connected to the unmanned underwater vehicle 51. Inside the pressure-resistant closed cavity, the energy accumulator 6, the filter 13, the electromagnetic valve 16, the hydraulic motor 26, the hydraulic motor adapter 27, the check valve 35, the throttle valve 36, the check valve 37 and hydraulic steel pipes and joints among all hydraulic devices form the hydraulic system of the invention.

As shown in fig. 3, the hydraulic oil circuit of the hydraulic system includes three functional oil circuits, namely an energy storage oil circuit, an energy release power generation oil circuit and an oil return oil circuit. As shown in fig. 1 to 3 and 6, the energy storage oil path is formed by sequentially connecting an ocean temperature difference energy capture device 48, a hydraulic steel pipe 50, a threaded hole 40, a one-way valve 35, a rib ring 5, an oil hole 41 and an energy accumulator 6; the energy-releasing power generation oil way is formed by sequentially connecting an energy accumulator 6, an oil hole 41, a rib ring 5, a throttle valve 36, a threaded hole 43, an electromagnetic valve 16, a hydraulic steel pipe 14, a filter 13, a hydraulic steel pipe 12, a hydraulic motor 26, a hydraulic motor adapter 27, a hydraulic steel pipe 25, a hydraulic steel pipe 23, a hydraulic steel pipe 24, an oil tank 3 and a leather bag 2; the return oil path is formed by sequentially connecting the leather bag 2, the oil cabin 3, the hydraulic steel pipe 24, a threaded hole 45, a one-way valve 37, a rib ring 5, a threaded hole 40, a hydraulic steel pipe 50 and an ocean temperature difference energy capturing device 48.

As shown in fig. 2a and fig. 2b, a gear speed increaser 30 and a hydraulic motor 26 of the power generation and energy storage system are connected through an elastic coupling 28, a generator 31 and the gear speed increaser 30 are coaxially and fixedly connected to a support frame 29, the support frame 29 is fixedly connected to the tail end of a support base plate 15, and the root of the support base plate 15 is fastened with a rib ring 5. The circuit board support 20, the circuit board 17 and the battery pack support 8 are sequentially connected and mounted on the boss on the inner side of the rear cover 9 layer by layer through bolts. The circuit board 17 is provided with a rectifying and filtering voltage stabilizing circuit 34, which can convert the alternating current generated by the generator 31 into stable direct current and charge the lithium battery pack 19.

As shown in fig. 4, the oil tank 3, the front tank 4 and the rib ring 5 are axially locked by the long pull rod 11, the rib ring 5 and the rear tank 7 are axially locked by the short pull rod 21, the long pull rod 11 and the short pull rod 21 are fastened by nuts, and the bottom of the oil tank 3 is provided with a plug 32 to prevent hydraulic oil in the oil tank 3 from leaking to the front tank 4. Grooves are designed on the outer circular surfaces of the front cover 1, the rib ring 5 and the rear cover 9, and sealing rings 38 are installed to realize axial sealing of the cabin body connection part. As shown in fig. 2 and 4, a plurality of threaded holes are uniformly distributed on the circumference of two ends of the pressure-resistant closed cavity, the front cover 1 is installed at the port of the oil tank 3, and the rear cover 9 is installed at the port of the rear tank 7 and is fastened by hexagon socket head cap screws 39.

As shown in fig. 5a to 5c, the rib ring 5 is provided with a screw hole 40, an oil hole 41, a screw hole 43, a screw hole 44, and a screw hole 45. The threaded hole 40, the oil hole 41, the threaded hole 43, the threaded hole 44, and the threaded hole 45 communicate with each other through an oil passage 42. The threaded hole 40 is communicated with the oil hole 41, so that the ocean temperature difference energy capture device 48 can fill oil into the energy accumulator 6 through an energy storage oil way; the oil hole 41 is communicated with the threaded hole 43, so that the energy accumulator 6 is filled with oil to the oil tank 3 through the energy-releasing power generation oil way, and simultaneously drives the hydraulic motor 26 to rotate; the threaded hole 40 is communicated with the threaded hole 45, so that the oil tank can fill the ocean thermal energy capture device 48 with oil through an oil return path. The rib ring 5 adopts a common valve element design scheme, so that the complexity of oil circuit layout is obviously reduced, the structural compactness of the energy conversion device 49 is improved, and the energy conversion device 49 is miniaturized and compacted.

As shown in fig. 5a to 5c, the check valve 35 is installed in the oil passage 42 to prevent the hydraulic oil in the accumulator 6 from reversely flowing into the ocean thermal energy capture device 48; the check valve 37 is arranged in the threaded hole 45, so that hydraulic oil in the marine temperature difference energy capturing device 48 can be prevented from reversely flowing into the oil tank 3; the throttle valve 36 is arranged inside the threaded hole 43 and can adjust the hydraulic oil flow of the energy-releasing power generation oil path; the pressure sensor 22 is installed in the threaded hole 44 for detecting the charging pressure of the accumulator 6.

The solenoid valve 16 is a two-position two-way normally closed solenoid valve. In the energy-releasing power-generating oil way, the electromagnetic valve 16 is electrified to conduct the oil way between the energy accumulator 6 and the oil tank 3; the electromagnetic valve 16 is powered off, the energy releasing and generating oil way is interrupted, and the energy storage oil way works. The solenoid valve 16 is a lifting zero-leakage solenoid valve, adopts a direct-acting working principle, has high flow speed and does not shake or generate noise during working.

As shown in figure 6, the interface of the leather bag 2 is arranged at a central counter bore of the oil tank 3, is fastened and fixed by the leather bag mounting flange 10 and is fastened by a hexagon head bolt 46. The design of the kneck of the leather bag 2 has a groove, realizes axial seal through the seal ring 47, prevents the gas in the leather bag 2 from entering the oil tank 3. The bladder 2 is initially filled with air at a pressure of 1bar (absolute) during installation.

The specific working process of the invention is as follows:

the cycle of the submerged and floating motion of the unmanned underwater vehicle 51 comprises three phases: a submergence preparation stage, a submergence stage and a floating stage. The hydraulic oil circuit of the energy conversion device 49 comprises three functional oil circuits, namely an energy storage oil circuit, an energy release power generation oil circuit and an oil return oil circuit. Referring to fig. 8, fig. 8 shows 7a-7d as referring to the power generation process at each stage of fig. 7a-7d, respectively. The present invention is installed outside the unmanned underwater vehicle 51, and performs a submerging and surfacing cycle along with the unmanned underwater vehicle 51. In a circulation section, an energy storage oil way works to convert ocean temperature difference energy into hydraulic energy and store the hydraulic energy in an energy accumulator 6; when the pressure value of the energy accumulator 6 reaches a set value, the energy-releasing power-generating oil circuit works, the electromagnetic valve 16 is opened, and the hydraulic motor 26 drives the generator 31 to rotate and generate power.

As shown in fig. 7a, in the preparation stage for diving, the unmanned underwater vehicle 51 initially floats on the water surface, and the ocean thermal energy capture device 48 of the present invention is immersed in surface warm sea water. At this stage, the phase change material inside the ocean thermal energy capture device 48 is in a liquid state, the oil tank 3 is filled with hydraulic oil, and the bladder 2 is compressed by the extrusion of the hydraulic oil, and the pressure is greater than 1 bar.

As shown in fig. 7b, during the submergence phase, the temperature gradually decreases as the submergence depth of the unmanned underwater vehicle 51 increases. When the water temperature is lower than the melting point of the phase-change material, the phase-change material begins to gradually solidify and contract, meanwhile, under the action of the air pressure of the leather bag 2, the oil return path begins to work, hydraulic oil sequentially passes through the hydraulic steel pipe 24, the one-way valve 37, the rib ring 5 and the hydraulic steel pipe 50 from the oil cabin 3 and is injected into the ocean temperature difference energy capturing device 48, and the hydraulic oil inside the ocean temperature difference energy capturing device 48 pushes the sealing piston 33 to move towards the phase-change material side.

As shown in fig. 7c, during the ascent phase, the unmanned underwater vehicle 51 gradually ascends and the water temperature gradually rises. When the water temperature is higher than the melting point of the phase-change material, the phase-change material gradually melts and expands, the phase-change material pushes the sealing piston 33 to move towards the hydraulic oil side in the ocean temperature difference energy capturing device 48, the energy storage oil way starts to work, and the hydraulic oil is injected into the energy accumulator 6 from the ocean temperature difference energy capturing device 48 through the hydraulic steel pipe 50, the one-way valve 35 and the rib ring 5 in sequence. In the process, the ocean temperature difference energy is converted into hydraulic potential energy.

As shown in fig. 7d, the pressure sensor 22 detects the pressure of the accumulator 6, when the pressure of the accumulator 6 reaches a set value, the energy-releasing and power-generating oil path starts to work, the electromagnetic valve 16 is opened, and the high-pressure oil in the accumulator 6 is injected into the oil tank 3 through the rib ring 5, the throttle valve 36, the electromagnetic valve 16, the hydraulic steel pipe 14, the filter 13, the hydraulic steel pipe 12, the hydraulic motor 26, the hydraulic motor adapter 27, the hydraulic steel pipe 25, the hydraulic steel pipe 23 and the hydraulic steel pipe 24 in sequence. In the process, the hydraulic motor 26 is driven to rotate by high-pressure oil, and the output torque of the hydraulic motor 26 drives the generator 31 to rotate and generate electricity through the elastic coupling 28 and the gear speed increaser 30; the current is converted and transmitted to the lithium battery pack 19 through the rectifying, filtering and voltage stabilizing circuit 34 of the circuit board 17. When the pressure of the accumulator 6 drops to zero, the solenoid valve 16 closes. The accumulator 6 can then continue to charge and discharge energy to generate electricity until the phase change material is completely melted.

After the unmanned underwater vehicle 51 returns to the surface, the present invention completes a complete cycle. The electrical energy stored in the lithium battery pack 19 can be supplied to the electrical components of the unmanned underwater vehicle 51 for use via the watertight penetration 18.

The present invention is not limited to the above-described embodiments. The foregoing description of the specific embodiments is intended to describe and illustrate the technical solutions of the present invention, and the above specific embodiments are merely illustrative and not restrictive. Those skilled in the art can make many changes and modifications to the invention without departing from the spirit and scope of the invention as defined in the appended claims.