Wireless charging magnetic coupling device for deep-sea unmanned underwater vehicle

Abstract

The invention provides a wireless charging magnetic coupling device for a deep-sea unmanned underwater vehicle, and belongs to the technical field of wireless charging of unmanned underwater vehicles. The underwater wireless charging magnetic coupling mechanism solves the problems that the design of an existing underwater wireless charging magnetic coupling mechanism does not consider the compression resistance in a deep sea environment, the power level is low, and the power density is small. The magnetic coupling device comprises a shell and a magnetic coupling mechanism, the magnetic coupling mechanism is installed on the outer side of the shell, the magnetic coupling mechanism comprises four transmitting coils, four receiving coils and a magnetic core, the four transmitting coils are arranged in a matrix mode, one receiving coil is correspondingly arranged above each transmitting coil, and the magnetic core is arranged in the shell. A magnetic core is arranged in the center of each transmitting coil, the magnetic cores are made of nanocrystalline strips, the nanocrystalline strips are attached to the outer sides of the transmitting coils and the outer sides of the receiving coils, and the adjacent coils in the four transmitting coils are wound in the reverse direction. The wireless charging device is mainly used for wireless charging of the underwater unmanned underwater vehicle.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless charging for underwater vehicles, and particularly relates to a magnetic coupling device for wireless charging of deep-sea underwater vehicles. Background Art

[0002] An underwater vehicle is a robot equipped with positioning, navigation, and observation equipment for performing ocean survey tasks. In the future, underwater vehicles will play an important role in ocean exploration. However, due to the limited volume of the battery of underwater vehicles, their endurance is limited and the cruising distance is short. They need to return to the base station for charging frequently. Traditional charging methods such as salvaging and replacing the battery and underwater wet plugging are labor-consuming, and their safety and concealment are poor, which have become important factors restricting the development of underwater vehicles.

[0003] The development of underwater wireless charging technology can solve a series of problems such as the sealing, complex operation, reliability, and lifespan of conventional electrical connection points in seawater, realize power transmission without physical connection, and improve the endurance and cruising range of underwater vehicles. It is an effective way to solve the problem of underwater power supply for underwater vehicles. However, when an underwater vehicle operates in deep-sea waters, the pressure of deep-sea seawater is relatively high, which poses a challenge to the anti-pressure design of the wireless charging magnetic coupling mechanism. At the same time, the underwater environment is complex. Due to low positioning accuracy and the influence of seawater currents, rotation or axial offset will occur during underwater wireless charging, resulting in problems such as a decrease in charging efficiency and unstable output power. Currently, most designs of magnetic coupling mechanisms for underwater wireless charging do not consider the anti-pressure problem in deep-sea environments, and have a low power level and a small power density. Summary of the Invention

[0004] In view of this, the present invention aims to provide a magnetic coupling device for wireless charging of deep-sea underwater vehicles to solve the problems that the existing magnetic coupling mechanism design for underwater wireless charging does not consider the anti-pressure problem in deep-sea environments, and has a low power level and a small power density.

[0005] To achieve the above object, the present invention adopts the following technical solutions: A magnetic coupling device for wireless charging of deep-sea underwater vehicles includes a housing and a magnetic coupling mechanism. The magnetic coupling mechanism is installed outside the housing. The magnetic coupling mechanism includes a transmitting coil, a receiving coil, and a magnetic core. There are four transmitting coils, which are arranged in a matrix. A receiving coil is correspondingly provided above each transmitting coil, and a magnetic core is provided at the center position of each transmitting coil.

[0006] Furthermore, the magnetic core adopts nanocrystalline strip.

[0007] Furthermore, nanocrystalline strip is attached to the outside of both the transmitting coil and the receiving coil.

[0008] Furthermore, adjacent coils among the four transmitting coils are wound in the reverse direction.

[0009] Furthermore, adjacent coils among the four receiving coils are wound in the reverse direction.

[0010] Furthermore, the size of the receiving coil is smaller than that of the transmitting coil.

[0011] Furthermore, the length of the transmitting coil is 250 mm and the number of turns is 10, and the length of the receiving coil is 180 mm and the number of turns is 6.

[0012] Furthermore, it further includes a wireless topology structure, and the wireless topology structure charges the unmanned underwater vehicle.

[0013] Furthermore, the wireless topology structure includes an input DC voltage Ubus and a filter capacitor Cbus , the input DC voltage U bus and the filter capacitor C bus are connected in parallel and then connected to an inverter circuit. S 1 、S 4 and S 2 、S 3 are two groups of switching tubes, which conduct alternately to form high-frequency alternating current. The topology circuit consists of the self-inductance of the transmitting coil L 1 and the resonant capacitor C 1, the self-inductance of the receiving coil L 2 and the resonant capacitor C 2 are connected in series. Through coil coupling, energy is transferred from the primary side to the secondary side. The secondary side is connected to a rectifier bridge, and the rectifier bridge consists of D 1 、D 3 and D 2 、D 4 two groups of switching tubes. The alternating current is rectified into direct current by the rectifier bridge and then connected in parallel to the load battery R 0 to supply power to the battery.

[0014] Furthermore, when the unmanned underwater vehicle approaches the wireless topology structure, the input DC voltage Ubus is 100 V and the load is 4.5 Ω.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. In the present invention, the adjacent small coils have currents flowing in opposite directions, and a main magnetic flux perpendicular to the gap can be formed at any gap, which is consistent with the direction of the leakage magnetic flux, increasing the coupling coefficient between the coils, increasing the power density, designing the receiving coil to be smaller than the transmitting coil, keeping the magnetic field generated by the transmitting coil unchanged. When the small receiving coil has axial and rotational offsets, it can maintain stable coupling within a larger offset range, while enhancing the anti-axial and anti-rotational offset capabilities of the magnetic coupling mechanism.

[0016] 2. Both the transmitting coil and the receiving coil of the magnetic coupling mechanism of the present invention are arc-shaped planar coils, and the arc-shaped coils can fit the outer shell of the underwater unmanned submersible, realizing a conformal design.

[0017] 3. The magnetic core of the present invention selects nanocrystalline ribbon, which can be bent into a suitable arc to fit the shape of the coil and the unmanned submersible.

[0018] 4. Both the transmitting coil and the receiving coil of the present invention are attached with nanocrystalline ribbon, enhancing the coupling and reducing the leakage magnetic flux. Description of the Drawings

[0019] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings: Figure 1 is a schematic structural diagram of the magnetic coupling mechanism; Figure 2 is a schematic diagram of the magnetic force direction of each coil; Figure 3 is a magnetic field cloud map; Figure 4 is a wireless topology circuit diagram; Figure 5 is a top view of the multi-angle anti-offset magnetic coupling mechanism; Figure 6 is a front view of the multi-angle anti-offset magnetic coupling mechanism; Figure 7 is a curve graph of the mutual inductance fluctuation of the axial offset of the magnetic coupling mechanism.

[0020] 1 - Transmitting coil, 2 - Receiving coil, 3 - Magnetic core, 4 - Outer shell. Detailed Embodiments

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. It should be noted that, without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other. The described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0022] See Figure 1-7Description of this embodiment: A wireless charging magnetic coupling device for an underwater unmanned submersible, characterized in that it includes a housing 4 and a magnetic coupling mechanism. The magnetic coupling mechanism is installed outside the housing 4. The magnetic coupling mechanism includes a transmitting coil 1, a receiving coil 2, and a magnetic core 3. There are four transmitting coils 1, which are arranged in a matrix. A receiving coil 2 is correspondingly provided above each transmitting coil 1. A magnetic core 3 is provided at the center position of each transmitting coil 1. The adjacent coils among the four transmitting coils 1 are wound in the reverse direction, and the adjacent coils among the four receiving coils 2 are wound in the reverse direction. The size of the receiving coil 2 is smaller than that of the transmitting coil 1.

[0023] In this embodiment, the wire diameter of the Litz wire selected for the coil is 4 mm. The structural dimensions of each small coil are exactly the same. The overall length of the transmitting coil 1 is 250 mm, the number of turns is 10 turns, the overall length of the receiving coil 2 is 180 mm, the number of turns is 6 turns, the gap between the coils is 10 mm, the radius of the transmitting coil 1 is 235 mm, the radius of the receiving coil 2 is 205 mm, the thickness of the nanocrystalline at the transmitting end is 0.2 mm, the length is 60 mm, the magnetic permeability is 1000, the thickness of the nanocrystalline at the receiving end is 0.2 mm, the length is 40 mm, the magnetic permeability is 1000. When the underwater unmanned submersible reaches the wireless charging base station, the transmitting coil is turned on, the input voltage is 100 V, the load is 4.5 Ω, and the output power is 1800 W. Since the coupling mechanism is symmetric in the axial and rotational directions, only the axial direction is taken for analysis. As Figure 7 shown, when the axial offset at the receiving end is ±30 mm, the maximum value of the mutual inductance fluctuation is 15%.

[0024] Both the transmitting coil 1 and the receiving coil 2 of the magnetic coupling mechanism of this device are arc-shaped planar coils. The arc-shaped coils can fit the outer shell of the underwater unmanned submersible, realizing a conformal design. The overall coil is divided into four small coils with a gap in the middle. Each coil bears pressure independently, reducing the pressure-bearing area to one-fourth. And a fixing structure can be added at the gap, greatly reducing the design difficulty of the pressure-resistant housing of the magnetic coupling mechanism. By winding the adjacent small coils in the reverse direction, the directions of the main magnetic flux and the leakage magnetic flux are the same at the gap, improving the power density of the magnetic coupling mechanism. The current flow direction of the receiving coil 2 is the same as that of the transmitting coil 1. Taking the transmitting coil 1 as an example, the schematic diagram of its magnetic force lines and current flow direction is as Figure 2 shown. The black arrow is the current flow direction. The adjacent small coils with opposite current flow directions can form a main magnetic flux perpendicular to the gap at any gap, which is the same as the direction of the leakage magnetic flux, increasing the coupling coefficient between the coils and increasing the power density. The size of the designed receiving coil 2 is smaller than that of the transmitting coil 1. When the magnetic field generated by the transmitting coil 1 remains unchanged, the small receiving coil 2 can maintain stable coupling within a larger offset range when there is an axial offset and a rotational offset, and at the same time enhances the anti-axial and anti-rotational offset capabilities of the magnetic coupling mechanism. As Figure 3It is the magnetic field nephogram of the magnetic coupling mechanism. The red area represents better coupling effect. The results show that a receiving coil with a smaller size can achieve stable coupling within a larger offset range.

[0025] Furthermore, the magnetic core 3 is made of nanocrystalline strip, which can be bent to a suitable radian to fit the shapes of the coil and the unmanned submersible. Nanocrystalline strips are attached to the outer sides of the transmitting coil 1 and the receiving coil 2 to enhance coupling and reduce magnetic leakage.

[0026] Furthermore, the wireless topology structure includes an input DC voltage Ubus and a filter capacitor Cbus , the input DC voltage U bus and the filter capacitor C bus are connected in parallel and then connected to an inverter circuit. S 1 、S 4 and S 2 、S 3 are two groups of switching tubes that conduct alternately to form high-frequency alternating current. The topology circuit consists of the self-inductance L 1 of the transmitting coil and the resonant capacitor C 1, the self-inductance L 2 of the receiving coil and the resonant capacitor C 2 connected in series. Through coil coupling, energy is transferred from the primary side to the secondary side. The secondary side is connected to a rectifier bridge, and the rectifier bridge is composed of D 1 、D 3 and D 2 、D 4 two groups of switching tubes. The alternating current is converted into direct current through the rectifier bridge and then connected in parallel to the load battery R 0 to supply power to the battery.

[0027] As Figure 4 shown, the topology selects SS to simplify the circuit complexity and reduce the weight of the receiving end. The secondary side adopts an uncontrolled rectifier circuit topology, where U bus is the input DC voltage, C bus , C0 are filter capacitors, S 1 、S 4, S 2 、S 3 are switching tubes of the inverter circuit, D 1 、 D 3, D 2 、D 4 are rectifier bridge diodes, U0, I0 are output voltage and current, C1, C2 are resonant capacitors, L1, L2 are self-inductances of the transmitting coil and the receiving coil, M is the mutual inductance between the transmitting coil and the receiving coil, R1, R2 are internal resistances of the coils, and R0 is the equivalent load of the battery of the underwater unmanned submersible. The input DC voltage Ubus It is connected in parallel with the filter capacitor C0 and then connected to the inverter circuit. S1, S4 and S2, S3 are two groups of switching tubes, which conduct alternately to form high-frequency alternating current. The topology circuit is composed of the transmitting coil L1 and the resonant capacitor C1, and the receiving coil L2 and the resonant capacitor C2 in series. Through coil coupling, energy is transferred from the primary side to the secondary side. The secondary side is connected to a rectifier bridge, which is composed of two groups of switching tubes D1, D3 and D2, D4. The alternating current is rectified into direct current by the rectifier bridge and connected in parallel to the load battery to supply power to the battery.

[0028] The expression of the equivalent load resistance Re of the full-bridge rectification / filter circuit on the secondary side circuit is as follows:

[0029] Among them, R o is the load resistance, U o is the charging voltage, I o is the charging current.

[0030] For the magnetic coupling wireless power transfer system, the operating frequency of the system is consistent with the resonant frequencies of the primary side circuit and the secondary side circuit, and the following formula also holds, as follows:

[0031] The expressions of the charging current and charging power are as follows:

[0032]

[0033] The expression of the system efficiency is as follows:

[0034] The embodiments of the present invention disclosed above are only used to help explain the present invention. The embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. According to the content of this specification, many modifications and changes can be made. These embodiments are selected and specifically described in this specification to better explain the principle and practical application of the present invention, so that those skilled in the art can well understand and utilize the present invention.

Claims

1. A magnetic coupling device for wireless charging of deep-sea unmanned submersibles, characterized in that: The invention comprises a shell (4) and a magnetic coupling mechanism, wherein the magnetic coupling mechanism is installed outside the shell (4), and comprises a transmitting coil (1), a receiving coil (2) and a magnetic core (3). The transmitting coils (1) are provided with four, and the four transmitting coils (1) are arranged in a matrix, and a corresponding receiving coil (2) is provided above each transmitting coil (1), and a magnetic core (3) is provided at the center of each transmitting coil (1).

2. A magnetic coupling device for wireless charging of a deep-sea unmanned submersible according to claim 1, characterized in that: The magnetic core (3) is made of nanocrystalline ribbon.

3. The wireless charging magnetic coupling device for deep-sea unmanned submersible according to claim 1, characterized in that: Nanocrystalline strips are attached to the outer sides of the transmitting coil (1) and the receiving coil (2).

4. The wireless charging magnetic coupling device for deep-sea unmanned submersible according to claim 1, characterized in that: Adjacent coils in the four transmitting coils (1) are wound in opposite directions.

5. A magnetic coupling device for wireless charging of a deep-sea unmanned submersible according to claim 4, characterized in that: Adjacent coils in the four receiving coils (2) are wound in opposite directions.

6. The wireless charging magnetic coupling device for deep-sea unmanned submersible according to claim 1, characterized in that: The size of the receiving coil (2) is smaller than the size of the transmitting coil (1).

7. The wireless charging magnetic coupling device for deep-sea unmanned submersible according to claim 1, characterized in that: The transmitting coil (1) has a length of 250 mm and a number of turns of 10, and the receiving coil (2) has a length of 180 mm and a number of turns of 6.

8. The wireless charging magnetic coupling device for deep-sea unmanned submersible according to claim 1, characterized in that: It also includes a wireless topology structure, which is used to charge the unmanned underwater vehicle.

9. A wireless charging magnetic coupling device for deep-sea unmanned submersibles according to claim 8, characterized in that: The wireless topology includes an input DC voltage Ubus With filter capacitor Cbus , input DC voltage U bus With filter capacitor C bus After parallel connection, it is connected to the inverter circuit. S 1 、S 4 and S 2 、S 3 is two sets of switch tubes, which are alternately turned on to form high-frequency alternating current. The topology circuit is composed of the self-inductance of the transmitting coil. L 1 and resonant capacitor C 1 ， Receiving coil self-inductance L 2 and resonant capacitor C 2 in series, the rectifier bridge consists of D 1 、 D 3 and D 2 、D 4Two sets of switch tubes are connected in parallel to the load battery R 0, power the battery.

10. A wireless charging magnetic coupling device for deep-sea unmanned submersibles according to claim 9, characterized in that: When the UUV is close to the wireless topology, the input DC voltage U bus is 100V and the load is 4.5Ω.

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