Underwater vehicle charging system and charging method

Abstract

The invention provides an underwater vehicle charging system and a charging method, and solves the problem that the loading capacity, the operation time and the operation flexibility of an underwater vehicle are affected as a heavy coupler needs to be carried at the vehicle end in the conventional underwater vehicle wireless charging system. According to the invention, the permanent magnet synchronous motor which must be carried by the underwater vehicle is used for energy supply, the battery of the underwater vehicle is directly charged through the electromotive force generated by the reverse rotation of the permanent magnet synchronous motor, and the situation that the load is increased by a coupler installed at the vehicle end in the conventional wireless charging process is avoided. The charging system comprises a charging device arranged underwater and a one-way clutch arranged between a transmission shaft of a permanent magnet synchronous motor of the underwater vehicle and a propeller. The charging device comprises a base platform, a mobile platform, a motor, a charging rod, a fixed electromagnet, a communication unit and a control unit. The motor converts electric energy obtained by the charging device into mechanical energy which is transmitted to the permanent magnet synchronous motor transmission shaft through the charging rod to drive the transmission shaft to rotate reversely.

Description

Technical Field

[0001] The present invention belongs to the technical field of underwater charging, and in particular relates to an underwater vehicle charging system and a charging method. Background Art

[0002] As an important maritime force, autonomous underwater vehicles are important tools for marine geological and geomorphological exploration, marine environmental observation, marine resource exploration, etc. However, due to the limitations of the size and load capacity of autonomous underwater vehicles, the battery capacity is limited, and the endurance problem has always restricted the further development of autonomous underwater vehicles. Since salvage and recovery charging requires human participation, researchers are actively exploring ways to achieve energy replenishment without salvage and recovery.

[0003] At present, wireless charging technology is widely used in energy supply of underwater vehicles because it avoids the leakage risk of underwater wet plugging and has certain transmission efficiency, such as Chinese patent applications CN202311226168.X and CN202311155076.7. However, the wireless charging system requires a heavier coupler on the underwater vehicle side, which greatly affects the load capacity, operation time and operation flexibility of the underwater vehicle.

[0004] To this end, the present invention provides an underwater vehicle charging device, which does not require a heavy coupler to be carried on the vehicle end, thereby reducing the impact of the charging system on the underwater vehicle's operating ability. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings of the existing underwater vehicle wireless charging system, which requires a heavy coupler to be carried on the vehicle end, affecting the underwater vehicle's load capacity, operation time and operation flexibility, and to provide an underwater vehicle charging system and charging method.

[0006] The concept of the present invention:

[0007] In view of the problem that the current wireless charging system needs to carry a coupler at the underwater vehicle end, the present invention considers how to solve the problem of charging itself without increasing or increasing the load of the underwater vehicle. To this end, the structure of the underwater vehicle is further studied, and it is found that the permanent magnet synchronous motor (located at the tail of the underwater vehicle, which is the propulsion motor of the underwater vehicle) that the underwater vehicle itself must carry is capable of serving as an energy supply device at the vehicle end, and the difference between its forward and reverse rotation can be utilized to enable it to take into account both driving and charging functions; however, in a complex underwater operating environment, if the function of the permanent magnet synchronous motor is to be fully utilized, it is also necessary to consider the impact of water flow on the system and the problem of the propeller on its output shaft following rotation during reversal. Therefore, it is necessary to optimize its structure so that it can achieve the goal of energy replenishment with low loss without increasing or increasing the underwater vehicle itself.

[0008] To achieve the above purpose, the technical solution provided by the present invention is:

[0009] A charging system for an underwater vehicle, which is special in that: it induces an induced voltage by driving the drive shaft of the permanent magnet synchronous motor of the underwater vehicle to reverse (the reverse here refers to the direction opposite to the rotation direction of the drive shaft of the permanent magnet synchronous motor when the underwater vehicle is sailing, that is, the rotation direction of the drive shaft of the permanent magnet synchronous motor when the underwater vehicle is sailing is defined as the positive direction) and the electrical system of the underwater vehicle stores and transforms the induced voltage and stores it in the battery of the underwater vehicle to achieve the purpose of charging; the electrical system of the underwater vehicle has the functions of controlling the operation of the permanent magnet synchronous motor and controlling the charging of the battery of the underwater vehicle;

[0010] The propulsion system of a conventional underwater vehicle only needs to work in the propulsion mode, that is, through the battery → controller → propeller (permanent magnet synchronous motor). At this time, the electrical system only needs to be responsible for controlling the motor. However, in the present invention, because the propulsion system needs to have both the propulsion mode and the charging mode, that is, the battery → controller → propeller and the battery ← controller ← propeller, the electrical system at this time needs to have both the functions of controlling the permanent magnet synchronous motor and controlling the battery charging. Therefore, while designing the charging system, the present invention also needs to modify the electrical system in the conventional underwater vehicle so that it has the function of controlling battery charging, and can switch between the two functions of controlling the motor and controlling battery charging as needed, and has the ability to monitor the battery current and voltage, and can determine whether the battery is full through the current and voltage information. This part of the modification is relatively easy to implement for those skilled in the art, and the controller can be optimized to be a battery charging and propulsion motor controller;

[0011] The charging system comprises a charging device arranged underwater, and a one-way clutch arranged between a drive shaft of a permanent magnet synchronous motor of the underwater vehicle and a propeller;

[0012] The charging device includes a base platform, a mobile platform, a motor, a charging rod, a fixed electromagnet, a communication unit and a control unit;

[0013] The base platform is provided with a watertight connector, which is connected to an external power supply via a watertight cable;

[0014] The motor is mounted on the base platform via a mobile platform, and its output shaft is coaxially connected to one end of the charging rod;

[0015] The end surface structure of the other end of the charging rod is adapted to the end surface structure of the transmission shaft of the permanent magnet synchronous motor of the underwater vehicle;

[0016] The fixed electromagnet is arranged in the base platform, and a vehicle fixing area is formed on the upper surface of the base platform;

[0017] The communication unit is arranged in the base platform, communicates with the underwater vehicle and the control unit, and determines whether the underwater vehicle has reached the vehicle fixing area;

[0018] The control unit is arranged in the base platform, and is used to control the on and off of the fixed electromagnet, the start and stop of the motor, and the position of the mobile platform on the base platform (i.e., the position of the mobile platform relative to the base platform, so as to align and connect the motor output shaft, the charging rod and the permanent magnet synchronous motor transmission shaft of the underwater vehicle installed on the movable platform);

[0019] When charging, the motor output shaft, the charging rod and the underwater vehicle permanent magnet synchronous motor drive shaft are coaxial; due to the introduction of the one-way clutch, when the underwater vehicle permanent magnet synchronous motor drive shaft reverses, the propeller will automatically disengage from the drive shaft, so the propeller will not follow the drive shaft to reverse, so it will not drive the surrounding water flow, and will not produce any power transmission function, thus avoiding unnecessary losses.

[0020] Furthermore, on the base platform, the docking area between the underwater vehicle permanent magnet synchronous motor drive shaft and the charging rod is a semi-enclosed structure. After the underwater vehicle is docked with the charging device, the propeller is located in the semi-enclosed structure; this can avoid the greater viscous resistance caused by the drive shaft rotating in an open water environment during reverse charging, and improve the charging efficiency of the system to a certain extent. In general, charging efficiency = output charging power / input total power, where input total power = output charging power + loss power. Since the above design avoids the greater viscous resistance caused by the drive shaft rotating in an open water environment during reverse charging, it reduces the loss caused by this part, and therefore, the charging efficiency of the system can be improved.

[0021] Furthermore, one end of the charging rod is adaptably connected to the motor output shaft via a flat key, and the other end is adaptably connected to the drive shaft of the underwater vehicle permanent magnet synchronous motor via a spline.

[0022] At the same time, the present invention also provides a method for charging an underwater vehicle using the underwater vehicle charging system, which is special in that it includes the following steps:

[0023] S1. When the underwater vehicle detects that the battery is low, it communicates with the charging device through the communication unit, determines the location of the charging device and gradually approaches the charging device;

[0024] S2. The charging device detects that the underwater vehicle has reached the vehicle fixing area, and the control unit turns on the fixing electromagnet to fix the underwater vehicle on the base platform of the charging device;

[0025] The communication unit communicates with the underwater vehicle to determine whether the underwater vehicle has sailed to an area where it can be charged and replenished with energy, and provides the control unit with a judgment condition on whether to turn on the fixed electromagnet; when the communication unit communicates with the underwater vehicle and obtains that the current position is a position where it can be charged and replenished with energy, the control unit receives the instruction and controls the fixed electromagnet to absorb the underwater vehicle to prepare for the next step of charging;

[0026] S3. The charging device control unit controls the movement of the mobile platform to ensure that the charging rod is adapted to be connected to the drive shaft of the permanent magnet synchronous motor of the underwater vehicle;

[0027] S4. The charging device control unit starts the motor, which drives the drive shaft of the permanent magnet synchronous motor of the underwater vehicle to rotate in the opposite direction, driving the permanent magnet synchronous motor rotor to cut the stator to generate a magnetic field, thereby inducing an induced voltage on the stator;

[0028] S5. The internal electrical system of the underwater vehicle stores and transforms the induced voltage generated by S4, and stores it in the battery of the underwater vehicle to complete the charging.

[0029] Furthermore, the charging rod is connected to the transmission shaft of the permanent magnet synchronous motor of the underwater vehicle through a spline adapter.

[0030] Working principle of the present invention:

[0031] When the underwater vehicle detects that the battery is insufficient, it communicates with the charging device, determines the location of the charging device and gradually approaches the charging device; when the charging device detects that the underwater vehicle has reached the specified location, the control unit turns on the fixed electromagnet to fix the underwater vehicle on the base platform of the charging device; the charging device control unit controls the movement of the mobile platform to ensure that the spline of the charging rod is connected to the spline set at the end of the underwater vehicle's transmission shaft; after confirming that the connection is good, the control unit starts the motor, and the motor drives the transmission shaft to rotate in the opposite direction. Since a one-way clutch is set between the transmission shaft and the propeller, the propeller will automatically disengage from the transmission shaft during the reversal process to reduce losses. At this time, the motor of the charging device drives the permanent magnet synchronous motor rotor to cut the stator through the transmission shaft to generate a magnetic field, thereby inducing an induced voltage on the stator; the internal electrical system of the underwater vehicle stores and transforms the induced voltage, and stores it in the vehicle battery to complete the charging.

[0032] Compared with conventional underwater energy supply devices, the present invention has the following advantages:

[0033] 1. The present invention has a simple structure and cleverly utilizes the permanent magnet synchronous motor that the underwater vehicle must carry for energy replenishment. The induced voltage generated by the reversal of the permanent magnet synchronous motor directly charges the underwater vehicle battery, avoiding the need to install a coupler on the vehicle end to increase the load for conventional wireless charging, thereby improving the underwater vehicle's load capacity, operation time and operation flexibility, and the effect is very significant. Since the propeller of the underwater vehicle is installed on the transmission shaft of the permanent magnet synchronous motor, the propeller is required to generate sufficient thrust to ensure the speed of the vehicle during forward navigation, and the propeller does not rotate during reverse charging to avoid additional charging losses. Therefore, a one-way clutch is added between the transmission shaft and the propeller. When reversing, the propeller will automatically disengage from the transmission shaft, and no power transmission function will be generated, thereby reducing unnecessary energy loss caused by the propeller during reverse charging.

[0034] 2. The design of the one-way clutch at the underwater vehicle end and the semi-enclosed structure of the charging device of the present invention reduces the loss during the energy replenishment process, avoids the greater viscous resistance caused by the rotation of the transmission shaft in the open water environment during reverse charging, and improves the charging efficiency.

[0035] 3. The present invention avoids the tedious and time-consuming process of salvaging the underwater vehicle for charging. When the autonomous underwater vehicle needs to be charged, it only needs to dock the underwater vehicle on the charging device to achieve power replenishment, which effectively improves the continuity, concealment and intelligence of the autonomous underwater vehicle.

[0036] 4. The charging method of the present invention effectively avoids the weight of the magnetic coupler that needs to be carried in the magnetic coupling resonance underwater wireless charging system, while avoiding the electromagnetic radiation generated by the magnetic coupler, thereby improving the safety and stability of the vehicle operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a schematic diagram of the overall structure of the underwater vehicle charging device of the present invention;

[0038] Figure 2 Schematic diagram of the underwater vehicle end structure of the present invention; wherein (a) is the underwater vehicle end surface structure, and (b) is the AA cross-sectional view in (a);

[0039] Figure 3 This is a flow chart of underwater docking and charging of the underwater vehicle charging device of the present invention.

[0040] The reference numerals are as follows:

[0041] 1- underwater vehicle, 2- permanent magnet synchronous motor, 21- permanent magnet synchronous motor stator, 22- permanent magnet synchronous motor rotor, 3- transmission shaft, 4- propeller, 5- one-way clutch, 6- spline, 7- charging device, 8- base platform, 9- mobile platform, 10- motor, 11- fixed electromagnet, 12- communication unit, 13- control unit, 14- watertight connector, 15- battery, 16- battery charging and propulsion motor controller, 17- charging rod, 18- semi-enclosed structure. DETAILED DESCRIPTION

[0042] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0043] like Figure 1 and Figure 2 The underwater vehicle charging system shown herein induces an induced voltage by driving the drive shaft 3 of the permanent magnet synchronous motor 2 of the underwater vehicle 1 to reverse (the permanent magnet synchronous motor 2 includes a permanent magnet synchronous motor stator 21 and a permanent magnet synchronous motor rotor 22, and the rotation direction of the drive shaft 3 of the permanent magnet synchronous motor 2 is defined as forward when the underwater vehicle 1 is sailing). The internal electrical system of the underwater vehicle 1 (i.e., the battery charging and propulsion motor controller 16 between the permanent magnet synchronous motor 2 and the battery 15 is connected, which has the functions of controlling the operation of the permanent magnet synchronous motor 2 and controlling the charging of the battery 15 of the underwater vehicle 1) stores and transforms the induced voltage, and stores it in the battery 15 of the underwater vehicle 1 to achieve the charging purpose.

[0044] The charging system includes a charging device 7 disposed underwater, and a one-way clutch 5 disposed between a drive shaft 3 of a permanent magnet synchronous motor 2 of an underwater vehicle 1 and a propeller 4. The charging device 7 includes a base platform 8, a mobile platform 9, a motor 10, a charging rod 17, a fixed electromagnet 11, a communication unit 12, and a control unit 13.

[0045] A watertight connector 14 is provided on the side of the base platform 8, and an external power supply is connected through a watertight cable. The power supply can be a mother ship on the water surface or a power supply device on the shore.

[0046] The motor 10 is installed on the base platform 8 through the mobile platform 9, and its output shaft is coaxially connected to one end of the charging rod 17 through a flat key (that is, the end face of the output shaft of the motor 10 and the end face of one end of the charging rod 17 are both provided with flat keys, which are matched with the flat keys); the other end of the charging rod 17 is connected to the transmission shaft 3 of the permanent magnet synchronous motor 2 of the underwater vehicle 1 through a spline 6 (that is, the end face of the other end of the charging rod 17 and the end face of the transmission shaft 3 are both provided with splines 6, which are matched with the spline 6); the motor 10 converts the electrical energy obtained by the charging device 7 into mechanical energy, and effectively transmits it to the transmission shaft 3 of the permanent magnet synchronous motor 2 through the charging rod 17, thereby driving the transmission shaft 3 to reverse.

[0047] The fixed electromagnet 11 is arranged in the base platform 8, and a vehicle fixing area is formed on the upper surface of the base platform 8, so as to fix the underwater vehicle 1 with the charging device 7, so as to ensure that the underwater vehicle 1 does not shake with the water flow during the charging process, thereby ensuring stability;

[0048] The communication unit 12 is arranged in the base platform 8, and communicates with the underwater vehicle 1 and the control unit 13 to determine whether the underwater vehicle 1 has reached the vehicle fixing area; during the working process, the communication unit 12 needs to work under the control of the control unit 13, and there is information transmission between the two;

[0049] The control unit 13 is arranged in the base platform 8, and is used to control the on and off of the fixed electromagnet 11, the start and stop of the motor 10, and the position of the mobile platform 9 on the base platform 8;

[0050] During charging, the output shaft of the motor 10, the charging rod 17 and the drive shaft 3 of the permanent magnet synchronous motor 2 of the underwater vehicle 1 are coaxial; due to the introduction of the one-way clutch 5, when the drive shaft 3 of the permanent magnet synchronous motor 2 of the underwater vehicle 1 is reversed, the propeller 4 will automatically disengage from the drive shaft 3, so the propeller 4 will not reverse with the drive shaft 3, so it will not drive the surrounding water flow, and will not produce any power transmission function, thereby reducing unnecessary energy loss caused by the propeller 4 during reverse charging.

[0051] On the base platform 8, the docking area between the permanent magnet synchronous motor 2 drive shaft 3 of the underwater vehicle 1 and the charging rod 17 is designed as a semi-enclosed structure 18. In this way, after the underwater vehicle 1 is docked with the charging device 7, the propeller 4 is located in the semi-enclosed structure 18; this can avoid the greater viscous resistance caused by the rotation of the drive shaft 3 in the open water environment during reverse charging, thereby improving the charging efficiency of the system to a certain extent.

[0052] At the same time, the present invention provides a method for charging an underwater vehicle using the underwater vehicle charging system. The underwater docking charging process is as follows: Figure 3 As shown, the following steps are included:

[0053] S1. When the underwater vehicle detects that the battery is low, it communicates with the charging device through the communication unit, determines the location of the charging device and gradually approaches the charging device;

[0054] S2. The charging device detects that the underwater vehicle has reached the vehicle fixing area, and the control unit turns on the fixing electromagnet to fix the underwater vehicle on the base platform of the charging device;

[0055] S3. The charging device control unit controls the movement of the mobile platform to ensure that the charging rod is adapted to be connected to the drive shaft of the permanent magnet synchronous motor of the underwater vehicle;

[0056] S4. The charging device control unit starts the motor, which drives the drive shaft of the permanent magnet synchronous motor of the underwater vehicle to rotate in the opposite direction, driving the permanent magnet synchronous motor rotor to cut the stator to generate a magnetic field, thereby inducing an induced voltage on the stator;

[0057] S5. The internal electrical system of the underwater vehicle stores and transforms the induced voltage generated by S4, and stores it in the battery of the underwater vehicle to complete the charging.

[0058] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be included in the protection scope of the present invention.

Claims

1. An underwater vehicle charging system, characterized in that: The underwater vehicle permanent magnet synchronous motor (2) is driven to reversely drive a transmission shaft (3) to induce an induced voltage, and the underwater vehicle electrical system stores and transforms the induced voltage and stores it in an underwater vehicle battery (15) to achieve the purpose of charging. The underwater vehicle electrical system has the functions of controlling the operation of the permanent magnet synchronous motor (2) and controlling the charging of the underwater vehicle battery (15); The charging system comprises a charging device (7) arranged underwater, and a one-way clutch (5) arranged between a drive shaft (3) of a permanent magnet synchronous motor (2) of an underwater vehicle and a propeller (4); The charging device (7) comprises a base platform (8), a mobile platform (9), a motor (10), a charging rod (17), a fixed electromagnet (11), a communication unit (12) and a control unit (13); The base platform (8) is provided with a watertight connector (14) which is connected to an external power supply via a watertight cable; The motor (10) is mounted on the base platform (8) via a mobile platform (9), and its output shaft is coaxially connected to one end of the charging rod (17); The end surface structure of the other end of the charging rod (17) is adapted to the end surface structure of the transmission shaft (3) of the underwater vehicle permanent magnet synchronous motor (2); The fixed electromagnet (11) is arranged in the base platform (8), and a vehicle fixing area is formed on the upper surface of the base platform (8); The communication unit (12) is arranged in the base platform (8) and communicates with the underwater vehicle and the control unit (13) to determine whether the underwater vehicle has reached the vehicle fixing area; The control unit (13) is arranged in the base platform (8) and is used to control the on and off of the fixed electromagnet (11), the start and stop of the motor (10), and the position of the mobile platform (9) on the base platform (8); During charging, the output shaft of the motor (10), the charging rod (17) and the transmission shaft (3) of the underwater vehicle permanent magnet synchronous motor (2) are coaxial.

2. The underwater vehicle charging system according to claim 1, characterized in that: On the base platform (8), the docking area between the underwater vehicle permanent magnet synchronous motor (2) drive shaft (3) and the charging rod (17) is a semi-enclosed structure (18); After the underwater vehicle is docked with the charging device (7), the propeller (4) is located in the semi-enclosed structure (18).

3. The underwater vehicle charging system according to claim 1 or 2, characterized in that: One end of the charging rod (17) is adaptably connected to the output shaft of the motor (10) via a flat key, and the other end is adaptably connected to the transmission shaft (3) of the underwater vehicle permanent magnet synchronous motor (2) via a spline (6).

4. A method for charging an underwater vehicle using the underwater vehicle charging system according to claim 1, characterized in that: The following steps are involved: S1. When the underwater vehicle detects that the battery is low, it communicates with the charging device through the communication unit, determines the location of the charging device and gradually approaches the charging device; S2. The charging device detects that the underwater vehicle has reached the vehicle fixing area, and the control unit turns on the fixing electromagnet to fix the underwater vehicle on the base platform of the charging device; S3. The charging device control unit controls the movement of the mobile platform to ensure that the charging rod is coaxially adapted to the drive shaft of the permanent magnet synchronous motor of the underwater vehicle; S4. The charging device control unit starts the motor, which drives the drive shaft of the permanent magnet synchronous motor of the underwater vehicle to rotate in the opposite direction, driving the rotor of the permanent magnet synchronous motor to cut the stator to generate a magnetic field, thereby inducing an induced voltage on the stator; S5. The electrical system of the underwater vehicle stores and transforms the induced voltage generated by S4, and stores it in the battery of the underwater vehicle to complete the charging.

5. The method for charging an underwater vehicle by the underwater vehicle charging system according to claim 4, characterized in that: In S3, the charging rod and the drive shaft of the permanent magnet synchronous motor of the underwater vehicle are connected through a spline adapter.

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