Wireless power transmitting device

Abstract

A wireless power transmitting device includes a first coil structure and a control circuit. The first coil structure includes a first circuit board and a plurality of coil conductors disposed on the first circuit board. The plurality of coil conductors includes at least one first capacitor structure. The straight-line distance between the first capacitor structure and the output end of the plurality of coil conductors is less than the straight-line distance between the first capacitor structure and the input end of the plurality of coil conductors, and the position of the first capacitor structure does not overlap with the position of the output end. The control circuit measures the first coil structure to determine the power transmission value and uses the power transmission value to determine whether a foreign object has entered the power transmission range between the wireless power transmitting device and the receiving device.

Description

Technical Field

[0001] This disclosure relates to a wireless power transmitting device having a coil structure, and more particularly to an electromagnetic resonant wireless power transmitting device having a capacitor structure incorporated within the coil structure. Prior Technology

[0002] In conventional technology, wireless power transfer (WPT) devices typically use inductive coupling for charging. Inductive coupling makes the transmitter (TX) and receiver (RX) of a WPT device susceptible to overheating or damage to hardware components due to excessive energy transmission caused by foreign object intrusion. Therefore, related technologies are often combined with foreign object detection (FOD) technology.

[0003] Conventional FOD technology typically requires multiple small sensing coils between the transmitter and receiver to sense the impact of foreign objects on magnetic field distribution or power transmission. These small sensing coils not only increase the complexity of the hardware structure but also raise manufacturing costs.

[0004] How to solve the problems caused by the small sensing coils while enabling wireless charging systems to have FOD technology is an important issue that needs to be addressed by those skilled in the art. Summary of the Invention

[0005] This disclosure provides a wireless power transmitting device. The wireless power transmitting device includes a first coil structure and a control circuit. The first coil structure includes a first circuit board and a plurality of coil conductors disposed on the first circuit board. The plurality of coil conductors includes at least one first capacitor structure, the straight-line distance between the first capacitor structure and the outlet end of the plurality of coil conductors is less than the straight-line distance between the first capacitor structure and the inlet end of the plurality of coil conductors, and the position of the first capacitor structure does not overlap with the position of the outlet end. The control circuit is coupled to the first coil structure. The wireless power transmitting device is used to transmit power to a receiving device through the plurality of coil conductors. The control circuit is used to measure the plurality of coil conductors to determine the power transmission value, and to determine whether a foreign object has entered the power transmission range between the wireless power transmitting device and the receiving device based on the power transmission value.

[0006] In summary, the wireless power transmitting device disclosed in this document, by incorporating a capacitor structure into the coil structure of the transmitting unit, causes the electromagnetic field of the coil structure to resonate with the capacitor structure, thereby giving the coil structure a higher quality factor (Q factor). This results in a significant change in the power transmission value when a foreign object intrudes into the power transmission range. By detecting this change in power transmission value, the wireless power transmitting device can accurately detect foreign objects.

[0007] Furthermore, when implementing foreign object detection, the wireless power transmission device disclosed in this document does not require any small sensing coil between the transmitting and receiving ends, which makes the wireless power transmission device have a simpler hardware structure and can significantly reduce its manufacturing cost. Simple Explanation of the Diagram

[0008] Figure 1A is a schematic diagram of a wireless charging system according to an embodiment of this disclosure. Figure 1B is a schematic diagram of the wireless charging system of the embodiment of Figure 1A when there is a foreign object. Figure 2A is a schematic diagram of a coil according to an embodiment of this disclosure. Figure 2B is a schematic diagram of a conductor according to an embodiment of this disclosure. Figure 3A is a schematic diagram of a conductor according to an embodiment of this disclosure. Figure 3B is a schematic diagram of a capacitor structure according to an embodiment of this disclosure. Figure 3C is a schematic diagram of a capacitor structure according to an embodiment of this disclosure. Figure 3D is a schematic diagram of a capacitor structure according to an embodiment of this disclosure. Figure 4A is a schematic diagram of a capacitor structure and an additional capacitor structure according to an embodiment of this disclosure. Figure 4B is a schematic diagram of a capacitor structure and an additional capacitor structure according to an embodiment of this disclosure. Implementation

[0009] The embodiments of this disclosure will be described below with reference to the relevant drawings. In the drawings, the same reference numerals denote the same or similar elements or method flows.

[0010] Please refer to Figure 1A, which is a schematic diagram of a wireless charging system 100 according to an embodiment of this disclosure. The wireless charging system 100 includes a transmitting device TRA 100 and a receiving device REC 100.

[0011] The transmitting device TRA100 can be used to wirelessly charge the receiving device REC100. The receiving device REC100 can be any device that needs to be charged, such as consumer electronic devices like mobile phones or laptops, or autonomous vehicles such as tracked unmanned transport vehicles, trackless unmanned transport vehicles, and drones.

[0012] In some embodiments, the transmitting device TRA100 and the receiving device REC100 can be applied to special environments without human intervention, such as unmanned factories. With this wireless charging system 100, unmanned transport vehicles, such as those mentioned above, can autonomously move to the power transmission range of the transmitting device TRA100 for wireless charging, enabling unmanned transport vehicles to operate automatically without interruption.

[0013] In the embodiment of Figure 1A, the transmitting device TRA100 includes a control circuit TRA110, a coil structure TRA120, and a power supply TRA130. The receiving device REC100 includes a control circuit REC110, a coil structure REC120, and an energy storage device REC130.

[0014] In the transmitting device TRA100, the power supply TRA130 can be used to provide power, and the transmitting device TRA100 can be wirelessly charged by the coil structure TRA120 inside the transmitting device TRA100.

[0015] The power supply TRA130 can be any type of battery or power generator to provide direct current or alternating current. The power supply TRA130 may include power management circuitry to regulate the transmission voltage and current sent by the transmitting device TRA100 to the receiving device REC100.

[0016] The transmitting device TRA100 can transmit power to the receiving device REC100, which has a coil structure REC120, in a resonant manner via the coil structure TRA120. In some embodiments, the transmitting device TRA100 can achieve magnetic resonance charging of the receiving device REC100 via a resonant frequency of 6.78MHz.

[0017] Specifically, the principle of electromagnetic resonance wireless charging technology is to tune the resonant coils in the coil structure TRA120 of the power transmitting device TRA100 and the coil structure REC120 of the receiving device REC100 to the same resonant frequency, and then perform wireless charging by transmitting energy through a magnetic resonance coupling mechanism without physical contact.

[0018] The coil structure TRA120 of the transmitting device TRA100 can convert electricity into a magnetic field to wirelessly transmit energy to the coil structure REC120 of the receiving device REC100. The structure and arrangement of the coil structure TRA120 are shown in Figures 2A and 2B.

[0019] Please refer to Figures 1A, 2A, and 2B simultaneously. Figure 2A is a schematic diagram of a coil structure TRA120 according to an embodiment of this disclosure, and Figure 2B is a schematic diagram of a coil conductor 120 according to an embodiment of this disclosure.

[0020] As shown in Figure 2A, the coil structure TRA120 consists of the first circuit board BRD1 and the coil conductor 120.

[0021] The first circuit board BRD1 can be a fixed medium, such as a printed circuit board (PCB). The coil conductor 120 can be wound around a position (e.g., the center point CEN1 in Figure 2A) to form a plurality of turns of coil, and the position of the plurality of turns of coil is fixed through the first circuit board BRD1.

[0022] The shape of the coil conductor 120 can be any shape, such as circular, quadrilateral, or octagonal, and can be adjusted and changed according to different application requirements. The number of coil turns is also unlimited (it can be 4, 8, 16, 32, etc.). The reason why the coil conductor 120 in Figure 2A is quadrilateral and has coils 120_1 to 120_4 is only for the convenience of illustrating the configuration of the coil structure TRA120, and does not mean that the coil conductor 120 must be quadrilateral, nor that the number of coils in the coil conductor 120 is limited to 4 turns. The coil conductor 120 may include an input terminal IT1 and an output terminal OT1. The input terminal IT1 and the output terminal OT1 are respectively connected to the two ends of the coil conductor 120 to allow current to flow through the multiple turns of the coil conductor 120. The input terminal IT1 can be connected to one end of the multiple turns of the multiple turns (e.g., the outermost coil). The output terminal OT1 can be connected to the other end of the multiple turns of the multiple turns (e.g., the outermost coil).

[0023] In some embodiments, the input terminal IT1 is connected to coil 120_4 and extends along a first direction D1, as shown in Figure 2A. In these embodiments, the output terminal OT1 is connected to coil 120_1 and extends from below coils 120_1 to 120_4, over the plurality of turns of coil, along the first direction D1, or extends outward from the innermost coil to the outermost coil.

[0024] In other embodiments, the input terminal IT1 is connected to coil 120_4 and extends along a second direction D2 perpendicular to the first direction D1, as shown in Figure 2B. In these embodiments, the output terminal OT1 is connected to coil 120_1 and also extends along the second direction D2. Assuming that coils 120_1 to 120_4 are disposed in a first plane in space, the second direction D2 can be considered to be perpendicular to the first plane.

[0025] In other embodiments, the input terminal IT1 may extend along a first direction D1, while the output terminal OT1 may extend along a second direction D2 (not shown).

[0026] A capacitor structure may be provided on the outermost turn of the plurality of turns of the coil conductor 120. As shown in the embodiment of Figure 2A, the "outermost turn" is coil 120_4. A first capacitor structure C1 may be provided on coil 120_4. Coil 120_4 may have at least one dielectric material, such as: paper, nylon, polystyrene, Teflon, ceramic, silicon, silicone oil, etc. If the dielectric material is a non-solid or non-liquid substance such as air, a gap may be formed on coil 120_4, and the gap may correspondingly form the first capacitor structure C1.

[0027] It is worth mentioning that the first capacitor structure C1 and the coil conductor 120 are integrally formed.

[0028] In different embodiments, the first capacitor structure C1 can be changed accordingly by replacing the fixing medium with a different material or adjusting the size of the gap.

[0029] As shown in Figure 2A, the straight-line distance between the first capacitor structure C1 and the output terminal OT1 is less than the straight-line distance between the first capacitor structure C1 and the input terminal IT1, and the position of the first capacitor structure C1 on the coil does not overlap with the position of each turn of the coil extending from the output terminal OT1.

[0030] In one embodiment, the first capacitor structure C1 is not necessarily limited to being disposed on coil 120_4 of coil conductor 120; it can also be disposed at any position of coils 120_1 to 120_3, as long as the straight-line distance between the position of the first capacitor structure C1 and the output terminal OT1 is shorter than the straight-line distance between the position of the first capacitor structure C1 and the input terminal IT1, the technical effect described in this disclosure document can be achieved. Furthermore, the number of first capacitor structures C1 disposed on coil conductor 120 can be multiple, and the number is not limited.

[0031] During wireless charging, current flows through coil conductor 120. Because a first capacitor structure C1 is configured on coil 120_4, the parasitic capacitive coupling effect on the coil can be effectively reduced, suppressing stray electric fields caused by parasitic capacitance, thereby reducing the electric field strength on the overall coil structure TRA120. Furthermore, the first capacitor structure C1 can form an inductor-capacitor resonance (LC resonance) circuit with coil conductor 120, giving the coil structure TRA120 a higher quality factor, which helps improve energy focusing efficiency and magnetic field stability.

[0032] Please also refer to Figures 1A and 2A. The control circuit TRA110 of the transmitting device TRA100 can be used to detect the process of wireless power transmission from coil structure TRA120 to coil structure REC120, and to adjust the transmission voltage of coil structure TRA120.

[0033] Specifically, the control circuit TRA110 may include a single-chip processor, microcontroller, or any processor to cause the coil structure TRA120 to generate or adjust the magnetic field it emits. Furthermore, the control circuit TRA110 may be further connected to measurement terminals STR1 and STR2. Measurement terminal STR1 is located at the output terminal OT1, and measurement terminal STR2 is located at the input terminal IT1. Through measurement terminals STR1 and STR2, the control circuit TRA110 can be coupled to the coil structure TRA120 and measure the coil structure TRA120 to determine a power transmission value.

[0034] In some embodiments, the power transmission value may be the voltage or phase difference between the voltage level at the input terminal IT1 and the voltage level at the output terminal OT1. In other embodiments, the power transmission value may also be the current flowing through the coil conductor 120 of the coil structure TRA120.

[0035] In the above embodiments, the control circuit TRA110 may set a reference value and compare the power transmission value with the reference value to determine whether there is a foreign object entering the power transmission range between the transmitting device TRA100 and the receiving device REC100.

[0036] In some embodiments, the reference value may be a voltage or current value corresponding to the power transmission value. The reference value may be set based on the placement environment of the first capacitor structure C1 in the transmitting device TRA100 and the capacitance of the first capacitor structure C1. The reference value relates to the electromagnetic capacitive resonance between the first capacitor structure C1 and the coil structure TRA120.

[0037] When a foreign object invades the power transmission range between the transmitting device TRA100 and the receiving device REC100, the foreign object will disrupt the electromagnetic field of the power transmission range, causing the LC resonant frequency of the coil structure TRA120 and the coil structure REC120 to shift, resulting in changes in the equivalent inductance and equivalent impedance of the system, which in turn will be reflected in changes in voltage and current.

[0038] Therefore, the control circuit TRA110 can detect changes in the power transmission values ​​(voltage and current) and compare the magnitude of the power transmission values ​​with the reference value to determine whether a foreign object has entered the power transmission range.

[0039] Under different environments, such as when the transmitting device TRA100 is mounted on insulating, metallic, or conductive materials, the equivalent inductance or equivalent impedance of the coil structure TRA120 may vary due to environmental differences, causing a shift in the reference value. By adjusting the capacitance of the first capacitor structure C1, the transmitting device TRA100 can recalibrate the reference value under these different operating environments to maintain a stable LC resonant frequency. This ensures that the power transmission values ​​measured by the measuring terminals STR1 and STR2 can still accurately determine the presence of foreign objects, thereby maintaining the reliability of foreign object detection.

[0040] It is worth mentioning that, in the various embodiments of this disclosure, the specific structure of the coil structure REC120 of the receiving device REC100 is the same as that of the coil structure TRA120 of the transmitting device TRA100. Figures 2A and 2B can be used to represent the coil structure REC120, which may also have a coil conductor 120 and a first capacitor structure C1 disposed on the coil conductor 120.

[0041] Furthermore, in one embodiment (e.g., Figure 1B), when the control circuit TRA110 determines that a foreign object (e.g., foreign object OJT1) has entered the power transmission range, the control circuit TRA110 can cause the power supply TRA130 to stop supplying power to the coil structure TRA120 or continue to supply power while simultaneously providing a signal that a foreign object has entered the power transmission range.

[0042] In summary, the wireless charging system 100 can achieve resonance between the electromagnetic field of the coil structure TRA120 and the first capacitor structure C1 by configuring a first capacitor structure C1 in the coil structure TRA120 of the transmitting device TRA100. This results in a higher quality factor for the coil structure TRA120, leading to a significant change in power transmission value when a foreign object OJT1 intrudes into the power transmission range. By detecting this change in power transmission value, the wireless charging system 100 can accurately detect foreign objects.

[0043] When performing foreign object detection, the wireless charging system 100 does not require any small sensing coils between the transmitting device TRA 100 and the receiving device REC 100, which makes the wireless charging system 100 have a simpler hardware structure and can significantly reduce its manufacturing cost.

[0044] Furthermore, although the wireless charging system 100 uses electromagnetic resonance wireless power transmission technology, it is not inherently prone to overheating due to the intrusion of foreign objects OJT1. However, the above-mentioned settings can still further enhance safety and reliability, and avoid the impact of interference from foreign objects OJT1 on wireless charging efficiency.

[0045] It is hereby further clarified that the foreign object detection technology proposed in this disclosure determines whether a foreign object has entered the power transmission range between the transmitting device TRA100 and the receiving device REC100 by comparing the changes in the power transmission value with a reference value. In some embodiments, the wireless charging system 100 only needs to identify the presence of a foreign object, without needing to identify the specific location of the foreign object within the transmission range, and can then select whether to stop power supply through the control circuit TRA110 to ensure system safety. In other embodiments, the coil structure TRA120 can be replaced with a segmented coil structure or multiple measuring terminals can be provided on the coil structure TRA120 to detect the specific location of the foreign object within the transmission range; however, these embodiments are not essential technical requirements of this disclosure.

[0046] Please refer to Figures 3A-3D. Figure 3A is a schematic diagram of a coil conductor 120 according to an embodiment of this disclosure. Figures 3B-3D are schematic diagrams of a first capacitor structure C1 according to different embodiments of this disclosure.

[0047] The coil conductor 120 in Figure 3A corresponds to the coil conductor 120 in Figure 2A. The coil conductor 120 in Figure 3A is also disposed on the first circuit board BRD1.

[0048] Figure 3A shows three different directions: a first direction D1, a second direction D2, and a third direction D3. These three directions are perpendicular to each other and can be considered as three axes in three-dimensional space. The complex coil of the coil conductor 120 is arranged on a first plane, which is a two-dimensional plane composed of the first direction D1 and the third direction D3. The input terminal IT1 and the output terminal OT1 are both located along the second direction D2 at a distance L1 from the complex coil, and both the input terminal IT1 and the output terminal OT1 extend along the first direction D1.

[0049] In Figure 3B, the first capacitor structure C1 includes a plurality of first extension arms ARM1 and a plurality of second extension arms ARM2. Each first extension arm ARM1 extends from the first side SD1 of the first gap GAP1, and each second extension arm ARM2 extends from the second side SD2 of the first gap GAP1. The lengths of both the first extension arms ARM1 and the second extension arms ARM2 are less than the distance from the first side SD1 to the second side SD2 of the first gap GAP1. The first extension arms ARM1 and the second extension arms ARM2 are staggered, and the distance between each first extension arm ARM1 and two adjacent second extension arms ARM2 is a first gap GAPA. The first extension arms ARM1 and the second extension arms ARM2 function as capacitor elements in the coil structure TRA120.

[0050] In some embodiments, the first spacing GAPA between the plurality of first extension arms ARM1 and the plurality of second extension arms ARM2 all have the same width.

[0051] In other embodiments, the plurality of first spacing GAPAs may have different widths depending on different usage requirements. In other words, the distances between the first extension arms ARM1 and the second extension arms ARM2 may be different. By setting first spacing GAPAs of different widths, the first capacitor structure C1 can have different capacitance values.

[0052] In the embodiment shown in Figure 3B, the first circuit board BRD1 is disposed on the first plane consisting of the first direction D1 and the third direction D3, and each of the first extension arms ARM1 and each of the second extension arms ARM2 are alternately disposed on the first plane.

[0053] The first capacitor structure C1 in Figure 3C has a plurality of first extension arms ARM1 and second extension arms ARM2, just like the first capacitor structure C1 in Figure 3B. Each of the first extension arms ARM1 and each of the second extension arms ARM2 in Figure 3C are also staggered.

[0054] The difference lies in the fact that in Figure 3C, the first extension arm ARM1 and the second extension arm ARM2 are staggered along a second direction D2 perpendicular to the first plane. Figure 3A shows a cross-sectional line SL3, which extends along a third direction D3, while Figure 3C is a cross-sectional view of the first capacitor structure C1 in Figure 2A along the cross-sectional line SL3.

[0055] In the 3D diagram, the first capacitor structure C1 includes a plurality of first extension arms ARM1 and a plurality of second extension arms ARM2, and functions as a capacitor element.

[0056] The first extension arm ARM1 extends from the first side SD1 of the first slot GAP1, and the second extension arm ARM2 extends from the second side SD2 of the first slot GAP1.

[0057] Two adjacent first extension arms ARM1 and two adjacent second extension arms ARM2 are separated by a first gap GAPA. Each first extension arm ARM1 is aligned with a corresponding second extension arm ARM2 in the third direction D3 and separated by a second gap GAPB. Specifically, the length of each first extension arm ARM1 plus the length of the corresponding second extension arm ARM2, plus the length of the second gap GAPB, equals the length of the first gap GAP1.

[0058] The second spacing GAPB between each first extension arm ARM1 and the corresponding second extension arm ARM2 cannot be aligned with the second spacing GAPB between an adjacent first extension arm ARM1 and another second extension arm ARM2 in the first direction D1. That is, any two adjacent second spacing GAPBs are not aligned in the first direction D1.

[0059] In some embodiments, the lengths of two adjacent first extension arms ARM1 cannot be the same, and the lengths of two adjacent second extension arms ARM2 cannot be the same. In this arrangement, adjacent second spacing GAPB can be staggered and not aligned.

[0060] It is worth mentioning that, in the embodiment of the 3D diagram, the first circuit board BRD1 is disposed on the first plane composed of the first direction D1 and the third direction D3, and the second spacing GAPB between each of the first extension arms ARM1 and each of the second extension arms ARM2 is staggered on the first plane.

[0061] In other embodiments, the plurality of second-pitch GAPBs between the first extension arm ARM1 and the second extension arm ARM2 are staggered in a second direction D2 perpendicular to the first plane. In these embodiments, the 3D diagram can be regarded as a cross-sectional view of the first capacitor structure C1 in the 3A diagram along the section line SL3.

[0062] Looking at the embodiments in Figures 3B to 3D, the structure of the extended arm in these embodiments can effectively disperse the electric field in the coil, reduce the local voltage in the coil, thereby suppressing the formation of hot spots and avoiding local concentration of the electric field.

[0063] Please refer to Figures 3A, 3B, 4A, and 4B simultaneously. Figure 4A is a schematic diagram of the first capacitor structure C1 and the additional capacitor structure AC1 according to an embodiment of this disclosure. Figure 4B is a schematic diagram of the first capacitor structure C1 and the additional capacitor structure AC2 according to an embodiment of this disclosure.

[0064] To increase the capacitance variation of the coil's capacitor structure, an additional capacitor structure can be added to the capacitor structure. Taking the first capacitor structure C1 in Figure 3B as an example, if it is desired to increase the capacitance variation of the first capacitor structure C1, an additional capacitor structure can be added to the first capacitor structure C1, making it present the structure shown in the embodiments of Figure 4A or Figure 4B.

[0065] In Figure 4A, the additional capacitor structure AC1 can function as a capacitor element on the coil 120_1 through the second gap GAP2. The additional capacitor structure AC1 can be connected in parallel with the first capacitor structure C1, and the additional capacitor structure AC1, the first capacitor structure C1, and the coil 120_1 are integrally formed.

[0066] A dielectric layer can be formed within the second gap GAP2, and the dielectric material used to fill the dielectric layer can be any material with a dielectric constant, so as to set the capacitance density of the additional capacitor structure AC1 without increasing the physical size of the additional capacitor structure AC1 itself.

[0067] By adding an additional capacitor structure AC1, the capacitance impedance on coil 120_1 can be adjusted, thereby achieving the purpose of adjusting the capacitance change.

[0068] In Figure 4B, the additional capacitor structure AC2 includes a plurality of first extension arms AC_ARM1 and a plurality of second extension arms AC_ARM2. Each first extension arm AC_ARM1 extends from the first side AC_SD1 of the second gap GAP2, and each second extension arm AC_ARM2 extends from the second side AC_SD2 of the second gap GAP2. The lengths of both the first extension arms AC_ARM1 and the second extension arms AC_ARM2 are less than the distance between the first side AC_SD1 and the second side AC_SD2 of the second gap GAP2.

[0069] The first capacitor structure C1 in Figure 4B corresponds to the first capacitor structure C1 of coil 120_1 in Figure 3A. The additional capacitor structure AC2 in Figure 4B can be disposed in the coil structure TRA120 in Figure 3A and connected in parallel with the first capacitor structure C1 in Figure 3A. Furthermore, the first circuit board BRD1 is disposed on the first plane composed of the first direction D1 and the third direction D3, and each of the first extension arms AC_ARM1 and each of the second extension arms AC_ARM2 are staggered along the third direction D3 on the first plane.

[0070] In summary, the wireless charging system 100 of this disclosure can achieve resonance between the electromagnetic field of the coil structure TRA120 and the first capacitor structure C1 by configuring a first capacitor structure C1 in the coil structure TRA120 of the transmitting device TRA100, thereby giving the coil structure TRA120 a high quality factor (Q factor). This results in a significant change in the power transmission value when a foreign object OJT1 intrudes into the power transmission range. By detecting this change in power transmission value, the wireless charging system 100 can accurately detect foreign objects.

[0071] When implementing foreign object detection, the wireless charging system 100 does not require any small sensing coils between the transmitting device TRA 100 and the receiving device REC 100, which makes the wireless charging system 100 have a simpler hardware structure and can significantly reduce its manufacturing cost.

[0072] The above are merely preferred embodiments of this disclosure. Various modifications and equivalent changes can be made to this disclosure without departing from its scope or spirit. In summary, all modifications and equivalent changes to this disclosure made within the scope of the following claims are within the scope of this disclosure.

[0073] 100: Wireless charging system TRA100: Transmitting device REC100: Receiving device TRA110, REC110: Control circuit TRA120, REC120: Coil Structure TRA130: Power Supply REC130: Energy Storage Device OJT1: Foreign object BRD1: First Circuit Board 120: Coil conductor 120_1, 120_2, 120_3, 120_4: Coils C1: First capacitor structure IT1: Input Terminal OT1: Outgoing cable end CEN1: Center point STR1, STR2: Measurement terminals D1: First Direction D2: Second Direction D3: Third direction L1: Length SL3: Profile Line ARM1,AC_ARM1: First extension arm ARM2,AC_ARM2: Second extension arm SD1, AC_SD1: First side SD2, AC_SD2: Second side GAP1: First Gap GAP2: Second Gap GAPA: First Spacing GAPB: Second Spacing AC1, AC2: Additional capacitor structure

Claims

1. A wireless power transmitting device, comprising: a first coil structure including a first circuit board and a plurality of coil conductors disposed on the first circuit board, wherein the plurality of coil conductors includes at least one first capacitor structure, the straight-line distance between the first capacitor structure and one of the output terminals of the plurality of coil conductors is less than the straight-line distance between the first capacitor structure and one of the input terminals of the plurality of coil conductors, and the position of the first capacitor structure does not overlap with the position of the output terminal; and a control circuit coupled to the first coil structure, wherein the wireless power transmitting device is used to transmit power to a receiving device through the first coil structure, and the control circuit is used to measure the first coil structure to obtain a power transmission value, and to determine whether a foreign object has entered a power transmission range between the wireless power transmitting device and the receiving device based on the power transmission value.

2. The wireless power transmitting device as claimed in claim 1, wherein in response to the control circuit determining that the foreign object has entered the power transmission range, the wireless power transmitting device stops supplying power to the first coil structure.

3. The wireless power transmission device as claimed in claim 1, wherein the power transmission value is a voltage at the input terminal to the output terminal or a current flowing through the plurality of turns of the coil conductor.

4. The wireless power transmitting device as claimed in claim 1, wherein the control circuit is further configured to: set a reference value based on a placement environment of the first capacitor structure in the wireless power transmitting device and a capacitance of the first capacitor structure; and compare the power transmission value with the reference value to determine whether the foreign object exists within the power transmission range.

5. The wireless power transmitting device as claimed in claim 1, wherein a first gap is formed on the plurality of coil conductors of the wireless power transmitting device, and the first capacitor structure is formed through the first gap, and the first capacitor structure and the plurality of coil conductors are integrally formed.

6. The wireless power transmission device as claimed in claim 5, wherein the first capacitor structure includes a plurality of first extension arms and a plurality of second extension arms, the first extension arms extending from a first side of the first slit, the second extension arms extending from a second side of the first slit, each of the first extension arms being spaced apart from a corresponding one of the first and second extension arms by a first distance, the lengths of the first extension arms and the lengths of the second extension arms being less than the distance from the first side to the second side of the first slit, and each of the first extension arms and each of the second extension arms being staggered.

7. The wireless power transmission device as claimed in claim 6, wherein the first circuit board is disposed on a first plane, and each of the first extension arms and each of the second extension arms are alternately disposed on the first plane.

8. The wireless power transmission device as claimed in claim 6, wherein the first circuit board is disposed on a first plane, and the first extension arms and the second extension arms are staggered in a second direction perpendicular to the first plane.

9. The wireless power transmission apparatus as described in claim 6, wherein the widths of the first gaps are all different.

10. The wireless power transmission device as claimed in claim 5, wherein the first capacitor structure includes a plurality of first extension arms and a plurality of second extension arms, the first extension arms extending from a first side of the first slit, the second extension arms extending from a second side of the first slit, each of the first extension arms being spaced apart by a first gap, each of the second extension arms being spaced apart by the first gap, and each of the first extension arms and its corresponding counterpart being spaced apart by a second gap, the adjacent second gaps being not aligned in a first direction.

Images