Wireless electricity taking device and system with heating prevention function

Abstract

The invention discloses a wireless electricity taking device and system with an anti-heating function. The electricity taking device comprises a magnetic core and a shielding plate. The magnetic core is suspended above the shielding plate; the magnetic core is a U-shaped magnetic core; an electricity taking coil is wound on the magnetic core; the shielding plate adopts an annular frame structure; the shielding plate of the annular frame structure can sense a current according to the current in the electricity-taking coil, and the current sensed by the shielding plate is in the same direction as the current in the electricity-taking coil. And a good anti-heating function is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless power supply, and in particular to a wireless power supply and system with an anti-heating function. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] During the operation of the wireless power transmission system, the power collector, as the core component of energy acquisition, is affected by surrounding metal objects (such as brackets), which may cause leakage magnetic field and eddy current loss, thereby causing overheating of the aluminum shielding plate. The existing technology usually reduces eddy current loss by increasing the distance between the aluminum shielding plate and the power collector. However, this not only increases the size of the power collector, but also affects its economy and application flexibility. Therefore, how to reduce the heating of the aluminum plate caused by the leakage magnetic field and improve the overall performance of the system has become a problem that needs to be solved urgently in the current technical field. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes a wireless power supply and system with anti-heating function, which has good anti-heating function, thereby improving the working stability and efficiency of the power supply.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] In the first aspect, a wireless power supply with an anti-heating function is proposed, comprising a magnetic core and a shielding plate; the magnetic core is suspended on the upper part of the shielding plate;

[0007] The magnetic core is a U-shaped magnetic core;

[0008] A power-taking coil is wound around the magnetic core;

[0009] The shielding plate adopts a ring frame structure;

[0010] The shielding plate with the annular frame structure can induce a current according to the current in the power taking coil, and the current induced by the shielding plate is in the same direction as the current in the power taking coil.

[0011] Furthermore, the shielding plate includes an upper plate, a lower plate, a front side plate and a rear side plate; the upper plate is connected to the bottom of the magnetic core, the lower plate is located at the lower part of the upper plate, and the upper plate and the lower plate are spaced a set distance apart, the front side plate is connected to the front ends of the upper plate and the lower plate, and the rear side plate is connected to the rear ends of the upper plate and the lower plate.

[0012] Furthermore, the opening of the U-shaped magnetic core faces upward.

[0013] Furthermore, the magnetic core includes a first magnetic arm, a second magnetic arm and a magnetic bottom; the first magnetic arm and the second magnetic arm are arranged on the magnetic bottom relatively, and the magnetic bottom is located on the upper part of the shielding plate.

[0014] Furthermore, a chamfer is provided at a connection point between the first magnetic arm and the magnetic bottom and at a connection point between the second magnetic arm and the magnetic bottom.

[0015] Furthermore, the first magnetic arm and the second magnetic arm are located at left and right ends of the magnetic bottom.

[0016] Furthermore, the first magnetic arm and the second magnetic arm are both perpendicular to the front side plate and the rear side plate.

[0017] Furthermore, the power taking coil is connected to the load module through a protection circuit;

[0018] The protection circuit includes a thermal relay, a resonant capacitor and a first inductor;

[0019] The thermal relay is connected in parallel with the resonant capacitor, and the power taking coil, the resonant capacitor, the first inductor and the load module are connected in series in sequence.

[0020] Furthermore, the thermal relay is in an open state when the temperature is less than a set warning threshold value; the thermal relay is in a closed state when the temperature is greater than or equal to the set warning threshold value.

[0021] In a second aspect, a wireless power transmission system is proposed, including the wireless power supply with anti-heating function proposed in the first aspect.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention proposes a wireless power supply and system with anti-heating function, the wireless power supply includes a magnetic core and a shielding plate; the magnetic core is suspended on the upper part of the shielding plate; a power collection coil is wound on the magnetic core; the magnetic core is a U-shaped magnetic core; the shielding plate adopts an annular frame structure; the shielding plate with an annular frame structure can induce a current according to the current in the power collection coil, and the current induced by the shielding plate is in the same direction as the current in the power collection coil; the magnetic field generated by the current induced by the shielding plate can effectively offset the alternating magnetic field generated by the power collection coil, significantly reduce the energy loss caused by the eddy current effect, and effectively prevent the temperature of the shielding plate from rising; in addition, the connection between the magnetic bottom and the magnetic arm of the wireless power supply is provided with a chamfered corner to achieve uniform distribution of the magnetic field and improve output stability; a thermal relay and a resonant capacitor are provided in the protection circuit to form an effective overheating protection mechanism, ensure the safe operation of the system under long-term high-current working conditions, and improve the working stability and efficiency of the power supply.

[0024] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings in the specification, which constitute a part of the present application, are used to provide further understanding of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application.

[0026] Figure 1 A schematic diagram of a wireless power supply structure with an anti-heating function disclosed in an embodiment;

[0027] Figure 2 A schematic diagram of the opposite magnetic field principle of a wireless power collector with an anti-heating function disclosed in an embodiment;

[0028] Figure 3 A current density diagram of a shielding plate disclosed in an embodiment;

[0029] Figure 4 A current density diagram of a conventional shielding layer disclosed in an embodiment;

[0030] Figure 5 A magnetic field density diagram of a shielding plate disclosed in an embodiment;

[0031] Figure 6 A magnetic field density diagram of a conventional shielding layer disclosed in an embodiment;

[0032] Figure 7 It is a schematic diagram of the structure of the magnetic core after adding rounded corners according to the embodiment disclosed;

[0033] Figure 8 is a current density diagram of the shielding plate when the magnetic core is rounded according to the embodiment;

[0034] Fig. 9 A side view of the current density of the shielding plate when the magnetic core is rounded according to the embodiment;

[0035] Fig.10 A magnetic field density diagram of a shielding plate when the magnetic core is rounded according to an embodiment;

[0036] Fig.11 A side view of the magnetic field density of the shielding plate when the magnetic core is rounded according to the embodiment;

[0037] Fig.12 This is a power supply circuit diagram disclosed in the embodiment.

[0038] Among them: 1. magnetic core, 2. shielding plate, 3. chamfered corners. DETAILED DESCRIPTION

[0039] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0040] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0041] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0042] In the present invention, the directions or positional relationships indicated by terms such as "upper", "lower", "left", "right", "front", "back", "side", and "bottom" are based on the directions or positional relationships shown in the accompanying drawings. They are relational words determined only for the convenience of describing the structural relationships of the various parts or elements of the present invention. They do not specifically refer to any part or element in the present invention and should not be understood as limitations on the present invention.

[0043] In the present invention, terms such as "fixed connection", "connected", "connection", etc. should be understood in a broad sense, indicating that it can be fixedly connected, integrally connected or detachably connected; it can be directly connected or indirectly connected through an intermediate medium. Relevant scientific research or technical personnel in this field can determine the specific meanings of the above terms in the present invention according to specific circumstances, and they should not be understood as limiting the present invention.

[0044] Example 1

[0045] In this embodiment, a wireless power supply with an anti-heating function proposed in the embodiment of the present application is disclosed. Figure 1-Figure 12 As shown, it includes a magnetic core 1 and a shielding plate 2;

[0046] The magnetic core 1 is suspended on the upper part of the shielding plate 2;

[0047] Magnetic core 1 is a U-shaped magnetic core;

[0048] A power taking coil is wound around the magnetic core 1;

[0049] The shielding plate 2 adopts an annular frame structure;

[0050] The shielding plate 2 with an annular frame structure can induce a current according to the current in the power taking coil, and the current induced by the shielding plate is in the same direction as the current in the power taking coil.

[0051] like Figure 1As shown, the shielding plate includes an upper plate, a lower plate, a front side plate and a rear side plate; the upper plate is connected to the bottom of the magnetic core, the lower plate is located at the lower part of the upper plate, and the upper plate and the lower plate are spaced apart by a set distance, the front side plate is connected to the front end of the upper plate and the lower plate, and the rear side plate is connected to the rear end of the upper plate and the lower plate. The upper plate, the lower plate, the front side plate and the rear side plate are connected end to end to form a ring frame structure.

[0052] Preferably, the shielding plate is made of aluminum.

[0053] The magnetic core 1 is suspended on the upper part of the shielding plate 2, and the interval between the magnetic core and the shielding plate is about 1 mm. According to Faraday's law of electromagnetic induction, Figure 2 As shown, the current I1 generated by the alternating current end will induce a current I2 in the same direction in the right wire. At this time, according to the right-hand rule, the direction of the generated magnetic field is as follows Figure 2 As shown by Figure 2 It can be seen that opposite magnetic fields are generated, that is, the circulating current I2 generated by the shielding plate and the alternating magnetic field generated by the current I1 on the power-taking coil on the magnetic core cancel each other out.

[0054] Using the short-circuit ring principle, the current density and magnetic field density generated by the shielding plate of this embodiment and the current density and magnetic field density generated by the traditional shielding layer are simulated and analyzed. The simulation results of the current density and magnetic field density generated by the shielding plate of this embodiment are as follows: Figure 3 , Figure 5 As shown in Figure 2, the simulation analysis results of the current density and magnetic field density generated by the traditional shielding layer are as follows: Figure 4 , Figure 6 shown; through Figure 3 It can be seen that by constructing Figure 1 The shielding plate shown can generate a circulating current in the same direction as the excitation current. The magnetic field generated by this circulating current can effectively offset the alternating magnetic field generated by the power pickup coil, significantly reduce the energy loss caused by the eddy current effect, reduce the temperature rise of the shielding plate, and improve the thermal management performance of the system. Figure 3 As shown, the shield plate produces a lower current density, such as Figure 5 As shown, the magnetic field generated by the circulating current generated by the shielding plate and the alternating magnetic field generated by the power taking coil cancel each other out, as shown in Figure 5 , Figure 6 As shown, the magnetic field strength generated by the shielding plate is significantly lower than that generated by the shielding layer of the traditional design. The wireless power supply with anti-heating function proposed in this embodiment can significantly reduce the eddy current loss of the shielding plate in practical applications and improve the long-term stability of the system.

[0055] The magnetic core 1 of this embodiment is a U-shaped magnetic core, and the opening of the U-shaped magnetic core faces upward.

[0056] Specifically, the magnetic core includes a first magnetic arm, a second magnetic arm and a magnetic bottom; the first magnetic arm and the second magnetic arm are relatively arranged on the magnetic bottom, the magnetic bottom is connected to the shielding plate, and a U-shaped magnetic core with an opening facing upward is formed through the first magnetic arm, the second magnetic arm and the magnetic bottom.

[0057] Wherein, power taking coils are wound around the first magnetic arm and the second magnetic arm.

[0058] The first magnetic arm and the second magnetic arm are located at the left and right ends of the magnetic bottom; the first magnetic arm and the second magnetic arm are both perpendicular to the front side plate and the rear side plate.

[0059] Currently, wireless power U-shaped power take-offs often adopt a right-angle design to facilitate manufacturing. This embodiment optimizes the structure of the power take-off magnetic core and performs magnetic field analysis. The magnetic core of this embodiment adopts a U-shaped chamfer design to achieve uniform distribution of the magnetic field. Figure 7 As shown, this structural improvement effectively improves the output stability of the power supply under different working conditions and reduces losses.

[0060] Specifically, a chamfer 3 is provided at the connection between the first magnetic arm and the magnetic bottom and at the connection between the second magnetic arm and the magnetic bottom.

[0061] like Figure 8-Figure 11 As shown, it is the simulation result of the current density and magnetic field density generated by the shielding plate when the core is rounded; Figure 5 is the simulation result of the magnetic field density generated by the shielding plate when the magnetic core is at right angles, and Figure 5 In comparison, when the magnetic core adopts a U-shaped chamfer design, the magnetic field strength of the shielding plate is smaller than that of a right-angle design. Through smooth edge transition, the magnetic field is more evenly distributed inside the magnetic core, avoiding strong magnetic field concentration at sharp edges, reducing eddy current loss and hysteresis loss, and reducing the refraction and concentration of magnetic field lines in the magnetic core, thereby improving the efficiency of the power collector. This uniformity helps to improve the efficiency of energy transmission. During the energy conversion process, more energy can be effectively converted into electrical energy instead of being lost. It enables the power collector to output electrical energy more stably under different working conditions and enables the power collector to better adapt to changing environments under different working conditions, such as distance changes, load changes, etc., so as to maintain the stability of the output. Traditional magnetic cores often have uneven magnetic fields at the edges. The U-shaped chamfer design can effectively reduce the edge effect, making the magnetic field more uniform throughout the magnetic core, avoiding the situation where the local magnetic field strength is too high or too low. This optimization can form a more uniform magnetic flux density distribution in the magnetic core, improve the utilization rate of the magnetic field, and enable the power collector to more effectively capture the electromagnetic energy of the original transmitter when working. It is one of the important optimizations in the wireless power supply system.

[0062] This embodiment also adds a protection circuit to the receiving end circuit, such as Fig.12As shown, the power taking coil is connected to the load module through a protection circuit; the protection circuit includes a thermal relay, a resonant capacitor C n and the first inductor L n ; The thermal relay is connected in parallel with the resonant capacitor, and the power coil L p2 , the resonant capacitor, the first inductor and the load module are connected in series in sequence.

[0063] The thermal relay is in an open state when the temperature is lower than the set warning threshold; the thermal relay is in a closed state when the temperature is greater than or equal to the set warning threshold.

[0064] Using thermal relay and resonant capacitor C n The parallel configuration is used as an overheat protection design in the circuit. When the power supply is working at high current for a long time, once the temperature reaches the set warning threshold, the thermal relay will be energized, causing the resonant capacitor to short-circuit. At this time, the inductor L n Loss and resonant capacitor C n Due to the resonant characteristics, the circuit behaves inductively, the power is reduced, the heating of the shielding plate is limited, and the safe operation of the system is ensured.

[0065] The load module includes a full-bridge inverter circuit and a power supply U D2 The full-bridge inverter circuit includes field effect transistors S5, S6, S7 and S8; the source of S5 is connected to the drain of S6; the source of S7 is connected to the drain of S8; the power supply U D2 One end of is connected to the drain of S5 and S7; the power supply U D2 The other end of the first inductor L is connected to the source of S6 and S8; n Connected to the source of S7; power coil L p2 Connect to the drain of S6.

[0066] In addition, in this embodiment, the first inductor L n A second inductor L is connected in series with the source of S7 f2 In this embodiment, a capacitor C is also provided. f2 , capacitor C f2 One end of the first inductor L n With the second inductor L f2 The connection circuit; capacitor C f2 The other end is connected to the drain of S6.

[0067] A wireless power supply with an anti-heating function disclosed in this embodiment includes a magnetic core and a shielding plate; the magnetic core is suspended on the upper part of the shielding plate; a power supply coil is wound on the magnetic core; the magnetic core is a U-shaped magnetic core; the shielding plate adopts a ring frame structure; the shielding plate with a ring frame structure can induce a current according to the current in the power supply coil, and the current induced by the shielding plate is in the same direction as the current in the power supply coil; the magnetic field generated by the current induced by the shielding plate can effectively offset the alternating magnetic field generated by the power supply coil, significantly reduce the energy loss caused by the eddy current effect, and effectively prevent the temperature of the shielding plate from rising; in addition, chamfers are provided at the connection between the magnetic bottom and the magnetic arm of the wireless power supply to achieve uniform distribution of the magnetic field and improve output stability; a thermal relay and a resonant capacitor are provided in the protection circuit to form an effective overheating protection mechanism, thereby ensuring the safe operation of the system under long-term high-current working conditions and improving the working stability and efficiency of the power supply.

[0068] Example 2

[0069] In this embodiment, a wireless power transmission system is disclosed, including a wireless power supply with an anti-heating function disclosed in Embodiment 1.

[0070] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A wireless power supply with anti-heating function, characterized in that: It includes a magnetic core and a shielding plate; the magnetic core is suspended on the upper part of the shielding plate; The magnetic core is a U-shaped magnetic core; A power-taking coil is wound around the magnetic core; The shielding plate adopts a ring frame structure; The shielding plate with the annular frame structure can induce a current according to the current in the power taking coil, and the current induced by the shielding plate is in the same direction as the current in the power taking coil.

2. A wireless power supply with anti-heating function as claimed in claim 1, characterized in that: The shielding plate includes an upper plate, a lower plate, a front side plate and a rear side plate; the upper plate is connected to the bottom of the magnetic core, the lower plate is located at the lower part of the upper plate, and the upper plate and the lower plate are spaced a set distance apart, the front side plate is connected to the front ends of the upper plate and the lower plate, and the rear side plate is connected to the rear ends of the upper plate and the lower plate.

3. A wireless power supply with anti-heating function as claimed in claim 2, characterized in that: The magnetic core comprises a first magnetic arm, a second magnetic arm and a magnetic bottom; the first magnetic arm and the second magnetic arm are arranged on the magnetic bottom relatively, and the magnetic bottom is located on the upper part of the shielding plate.

4. A wireless power supply with anti-heating function as claimed in claim 3, characterized in that: A chamfer is provided at a connection point between the first magnetic arm and the magnetic bottom and at a connection point between the second magnetic arm and the magnetic bottom.

5. The wireless power supply with anti-heating function as claimed in claim 3, characterized in that: The first magnetic arm and the second magnetic arm are both perpendicular to the front side plate and the rear side plate.

6. A wireless power supply with anti-heating function as claimed in claim 3, characterized in that: The first magnetic arm and the second magnetic arm are located at the left and right ends of the magnetic bottom.

7. The wireless power supply with anti-heating function as claimed in claim 1, characterized in that: The opening of the U-shaped core faces upward.

8. The wireless power supply with anti-heating function as claimed in claim 1, characterized in that: The power taking coil is connected to the load module through a protection circuit; The protection circuit includes a thermal relay, a resonant capacitor and a first inductor; The thermal relay is connected in parallel with the resonant capacitor, and the power taking coil, the resonant capacitor, the first inductor and the load module are connected in series in sequence.

9. A wireless power supply with anti-heating function as claimed in claim 8, characterized in that: The thermal relay is in an open state when the temperature is lower than the set warning threshold; the thermal relay is in a closed state when the temperature is greater than or equal to the set warning threshold.

10. A wireless power transmission system, characterized in that: A wireless power collector with anti-heating function comprising any one of claims 1 to 9.

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