KR102791159B1 - Wireless charging assembly and wireless charging system comprising the same - Google Patents

Abstract

According to one aspect of the present invention, a wireless charging assembly is provided, including a power coil for transmitting or receiving power, and a communication module disposed above or below the power coil and transmitting or receiving information associated with the power based on capacitive coupling.

Description

{WIRELESS CHARGING ASSEMBLY AND WIRELESS CHARGING SYSTEM COMPRISING THE SAME}

The present invention relates to a wireless charging assembly and a wireless charging system including the same.

Among the methods of transmitting power wirelessly, the method that utilizes inductive coupling uses the principle that when the strength of the current flowing in one of two adjacent coils is changed, an induced electromotive force is generated in the other coil.

In the wireless power transmission method using this inductive coupling, a method of establishing a communication channel between the power transmission side and the power reception side has been introduced for the stability of the operation. Specifically, the Wireless Power Consortium (WPC), a standardization organization for wireless power transmission, has specified in-band, time-multiplexing, and out-of-band methods in its standard documents.

However, the communication channel construction methods introduced so far, including the above method, have clear limitations, such as reducing the efficiency of wireless power transmission or being subject to power interference when performing communication.

The purpose of the present invention is to solve all of the problems of the above-mentioned prior art.

In addition, another purpose of the present invention is to establish a separate communication channel based on capacitive coupling in a wireless power transmission method using inductive coupling.

A representative configuration of the present invention to achieve the above purpose is as follows.

According to one aspect of the present invention, a wireless charging assembly is provided, including a power coil for transmitting or receiving power, and a communication module disposed above or below the power coil and transmitting or receiving information associated with the power based on capacitive coupling.

According to another aspect of the present invention, a wireless charging system is provided, comprising a first wireless charging assembly and a second wireless charging assembly, wherein the first wireless charging assembly comprises a first power coil for transmitting power, and a first communication module disposed above the first power coil and transmitting or receiving information associated with the power based on capacitive coupling, and wherein the second wireless charging assembly comprises a second power coil for receiving the power, and a second communication module disposed below the second power coil and transmitting or receiving the information based on capacitive coupling.

In addition, other wireless charging assemblies and other wireless charging systems according to the technical idea of the present invention are further provided.

According to the present invention, by establishing a separate communication channel based on capacitive coupling in a wireless power transmission method using inductive coupling, the influence of power interference can be minimized when performing communication between a power transmitting side and a power receiving side.

In addition, according to the present invention, by constructing a separate communication channel based on capacitive coupling as described above, power transmission and communication can be performed separately, and stable communication performance (e.g., low power consumption, high signal-to-noise ratio (SNR), and high data transmission speed) can be secured.

FIG. 1 is a block diagram exemplarily illustrating a wireless charging system according to one embodiment of the present invention.
FIG. 2 is a diagram schematically illustrating components of a wireless charging system according to one embodiment of the present invention.
FIG. 3 is a drawing exemplarily illustrating the shapes of a first communication module and a second communication module according to one embodiment of the present invention.
FIG. 4 is an exploded perspective view exemplarily illustrating a wireless charging system including a first shielding material and a second shielding material according to one embodiment of the present invention.
FIG. 5 is a diagram exemplarily illustrating an equivalent circuit model of a first communication module and a second communication module according to one embodiment of the present invention.
FIG. 6 is a drawing exemplarily illustrating an equivalent circuit model of a first wireless charging assembly according to one embodiment of the present invention.
FIG. 7 is a diagram exemplarily illustrating a conceptual diagram of a wireless charging system according to one embodiment of the present invention.
FIG. 8 is a drawing illustrating an example of implementing a first communication module or a second communication module according to one embodiment of the present invention.
FIG. 9 is a diagram illustrating the results of simulating the operation of a wireless charging system based on a first communication module and a second communication module.

The detailed description of the present invention set forth below refers to the accompanying drawings which illustrate specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention, while different from each other, are not necessarily mutually exclusive. For example, specific shapes, structures, and characteristics described herein may be modified and implemented from one embodiment to another without departing from the spirit and scope of the invention. It should also be understood that the positions or arrangements of individual components within each embodiment may be changed without departing from the spirit and scope of the invention. Accordingly, the detailed description set forth below is not to be taken in a limiting sense, and the scope of the present invention is to be taken to encompass the scope of the claims and all equivalents thereof. Like reference numerals in the drawings represent the same or similar elements throughout the several aspects.

Hereinafter, various preferred embodiments of the present invention will be described in detail with reference to the attached drawings so that a person having ordinary skill in the art to which the present invention pertains can easily practice the present invention.

FIG. 1 is a block diagram exemplarily illustrating a wireless charging system (10) according to one embodiment of the present invention. In addition, FIG. 2 is a diagram schematically illustrating components of a wireless charging system (10) according to one embodiment of the present invention.

Referring to FIGS. 1 and 2, a wireless charging system (10) according to one embodiment of the present invention may include a first wireless charging assembly (100) and a second wireless charging assembly (200).

According to one embodiment of the present invention, the first wireless charging assembly (100) and the second wireless charging assembly (200) can be divided into a side for transmitting power and a side for receiving power, and can be included in different devices, respectively. For example, the first wireless charging assembly (100) can be included in a charging device (e.g., a wireless charger located near a center fascia of a vehicle) as a side for transmitting power, and the second wireless charging assembly (200) can be included in a user device (e.g., a smartphone) as a side for receiving power.

According to one embodiment of the present invention, the first wireless charging assembly (100) may include a first power coil (110) and a first communication module (120). In addition, the second wireless charging assembly (200) may include a second power coil (210) and a second communication module (220). Since the components of the first wireless charging assembly (100) and the second wireless charging assembly (200) correspond to each other (i.e., the first power coil (110) and the second power coil (210), and the first communication module (120) and the second communication module (220) may each be configured as a pair), the following description will focus on the components of the first wireless charging assembly (100).

First, the first power coil (110) according to one embodiment of the present invention can perform a function of transmitting (or receiving) power. In addition, the second power coil (210) according to one embodiment of the present invention can perform a function of receiving (or transmitting) power.

Specifically, the first power coil (110) and the second power coil (210) can transmit or receive power based on inductive coupling, and this inductive coupling can be formed between the first power coil (110) and the second power coil (210) when the first power coil (110) and the second power coil (210) are arranged to face each other within a predetermined range.

Next, the first communication module (120) according to one embodiment of the present invention may be placed above the first power coil (110). In addition, the second communication module (220) according to one embodiment of the present invention may be placed below the second power coil (210). Specifically, the first communication module (120) and the second communication module (220) may be placed between the first power coil (110) and the second power coil (210) corresponding to the first power coil (110) and the second power coil (210) being placed to face each other.

According to one embodiment of the present invention, the first communication module (120) may not be formed in the same shape (e.g., coil shape) as the first power coil (110), but may be formed in an open circuit (or open loop) shape, that is, a shape that is open (or open) in at least one outer radial direction of the first power coil (110). For example, as shown in (a) and (b) of FIGS. 2 and 3, the first communication module (120) may be formed to be orthogonal to at least a portion of the first power coil (110), and more specifically, at least a portion of the first communication module (120) may be formed in a direction orthogonal to the central axis of the first power coil (110). If the shape of the first communication module (120) is formed in the same shape (or direction) as that of the first power coil (110), the current flowing in the first power coil (110) may be induced in the first communication module (120), which may deteriorate the communication quality. Therefore, it is preferable that the first communication module (120) be formed perpendicularly or in a direction perpendicular to the first power coil (110) as much as possible.

Likewise, according to one embodiment of the present invention, the second communication module (220) may not be formed in the same shape (e.g., coil shape) as the second power coil (210), but may be formed in an open circuit (or open loop) shape, that is, a shape that is open (or open) in at least one outer radial direction of the second power coil (210). For example, as shown in (a) and (b) of FIGS. 2 and 3, the second communication module (220) may be formed to be orthogonal to at least a portion of the second power coil (210), and more specifically, at least a portion of the second communication module (220) may be formed in a direction orthogonal to the central axis of the second power coil (210). If the shape of the second communication module (220) is formed in the same shape (or direction) as that of the second power coil (210), the current flowing in the second power coil (210) may be induced in the second communication module (220), which may deteriorate the communication quality. Therefore, it is preferable that the second communication module (220) be formed as vertically or in a direction perpendicular to the second power coil (210) as possible.

Meanwhile, according to one embodiment of the present invention, since the first communication module (120) and the second communication module (220) are formed in the shape as described above (specifically, since the first communication module (120) and the second communication module (220) formed in the same shape are arranged to face each other), capacitive coupling may be formed between the first communication module (120) and the second communication module (220). This capacitive coupling is a coupling method different from the inductive coupling formed between the first power coil (110) and the second power coil (210), and may be used to establish a communication channel between the first communication module (120) and the second communication module (220). Since the direction of a signal including information transmitted based on capacitive coupling is orthogonal to the direction of an induced electromotive force transmitted based on inductive coupling, the first communication module (120) and the second communication module (220) can transmit or receive information (or signals) while minimizing the influence of power interference.

Meanwhile, according to one embodiment of the present invention, information transmitted or received between the first communication module (120) and the second communication module (220) may be information associated with power transmitted or received by the first power coil (110) and the second power coil (210). Such information may include, for example, information regarding the power transmission capability of the power transmitting side, information regarding the device of the power receiving side, information regarding the charging status of the power receiving side, etc. However, it should be noted that the information associated with power is not necessarily limited to the above examples and may be variously changed within a scope that can achieve the purpose of the present invention.

Although the components of the first wireless charging assembly (100) and the second wireless charging assembly (200) have been described above, it is obvious that other components may be included in the first wireless charging assembly (100) and the second wireless charging assembly (200).

For example, referring to FIG. 4 (i.e., an exploded perspective view showing a state in which a first wireless charging assembly (100) and a second wireless charging assembly (200) are arranged to face each other for wireless charging), the first wireless charging assembly (100) and the second wireless charging assembly (200) may each include a first shielding material (130) and a second shielding material (230). The first shielding material (130) may be arranged below the first power coil (110), and thus, the first wireless charging assembly (100) may be arranged in the order of the first communication module (120), the first power coil (110), and the first shielding material (130). In addition, the second shielding material (230) may be placed on the upper portion of the second power coil (210), and accordingly, the second wireless charging assembly (200) may be placed in the order of the second shielding material (230), the second power coil (210), and the second communication module (220). Meanwhile, the first shielding material (130) and the second shielding material (230) may be formed of ferrite, and may perform a function of shielding a magnetic field when the first power coil (110) and the second power coil (210) transmit or receive power.

FIG. 5 is a drawing exemplarily illustrating an equivalent circuit model of a first communication module (120) and a second communication module (220) according to one embodiment of the present invention.

Referring to FIG. 5, self-capacitance (C1, C2) may be formed in each of the first communication module (120) and the second communication module (220). In addition, mutual capacitance (C3, C4) may be formed between the first communication module (120) and the second communication module (220).

According to one embodiment of the present invention, when information related to power is transmitted or received using a communication channel established between a first communication module (120) and a second communication module (220), the lower the self-capacitance (C1, C2) and the higher the mutual capacitance (C3, C4), the more stable communication performance can be secured.

In a situation where it is difficult to secure an appropriate level of self-capacitance (C1, C2) or mutual capacitance (C3, C4) with only the first communication module (120) and the second communication module (220), a method of securing stable communication performance by using other elements may be considered. For example, the self-capacitance (C1, C2) of each of the first communication module (120) and the second communication module (220) may be offset by an inductor (L) to be described later. As another example, the mutual capacitance (C3, C4) between the first communication module (120) and the second communication module (220) may be formed to have a very low value, such as pF, in which case the frequency of the pulse signal used by the first communication module (120) and the second communication module (220) to transmit or receive information associated with power may be used at a frequency of MHz or higher. These frequencies can be formed to be values greater than the frequency of the current flowing in the first power coil (110) or the second power coil (210), and for example, a frequency of 6.78 MHz, 13.56 MHz, etc., as a frequency of the ISM (Industrial Scientific and Medical) band can be used.

FIG. 6 is a drawing exemplarily illustrating an equivalent circuit model of a first wireless charging assembly (100) according to one embodiment of the present invention.

Referring to Fig. 6, inductors (L) may be arranged in parallel at both ends of the first communication module (120). These inductors (L) may offset the self-capacitance (C1) of the first communication module (120) and increase the size of a signal transmitted or received through the first communication module (120).

In addition, a plurality of capacitors (C5, C6) may be arranged on a path (T1) through which a signal is transmitted from an MCU (Micro Controller Unit) (140) to a first communication module (120). These plurality of capacitors (C5, C6) may function as a filter (e.g., a high-pass filter) to remove unnecessary signals such as noise.

In addition, a comparator (COMP) may be arranged on a path (T2) through which a signal is transmitted from the first communication module (120) to the MCU (140). This comparator (COMP) may perform a function of determining the level (High or Low) of a signal, i.e., a pulse signal, received from the first communication module (120). According to one embodiment of the present invention, the pulse signal used by the first communication module (120) to transmit or receive information related to power may be synchronized based on the frequency of the current flowing in the first power coil (110) (for example, if the frequency of the current flowing in the first power coil (110) is 120 kHz, it may be synchronized to a frequency corresponding to 1/N times that frequency ("N" is a natural number)), and the comparator (COMP) may determine the level (High or Low) of the pulse signal by referring to the number of pulses specified in a state in which the pulse signal is synchronized based on the frequency of the current flowing in the first power coil (110). Information associated with the power contained in the pulse signal can be encoded or decoded based on these determination results.

Meanwhile, since the equivalent circuit model of the second wireless charging assembly (200) can be generated with the same structure as the equivalent circuit model of the first wireless charging assembly (100), a detailed description thereof will be omitted.

Fig. 7 is a diagram exemplarily illustrating a conceptual diagram of a wireless charging system (10) according to one embodiment of the present invention. Specifically, Fig. 7 is a diagram additionally illustrating components related to power transmission in the equivalent circuit model examined in Figs. 5 and 6.

Referring to FIG. 7, the MCU (140) included in the first wireless charging assembly (100) can drive the inverter (150) to supply alternating current (AC) power to the first power coil (110). In addition, the MCU (240) included in the second wireless charging assembly (200) can detect the power received by the second power coil (210) using a converter (ADC). Here, in the process in which the first power coil (110) and the second power coil (210) transmit or receive power, it is obvious that, in addition to the first power coil (110) and the second power coil (210), an inverter (150), a tank circuit (e.g., a resonant tank) (160, 260), a rectifier (250), etc. can operate together.

In addition, the MCU (140) included in the first wireless charging assembly (100) and the MCU (240) included in the second wireless charging assembly (200) can transmit or receive information associated with power using a communication channel established based on the capacitive coupling of the first communication module (120) and the second communication module (220) during a process of transmitting or receiving power (it can also be understood that the first communication module (120) and the second communication module (220) transmit or receive the corresponding information). For example, the MCU (140) included in the first wireless charging assembly (100) can transmit information regarding the power transmission capability of the power transmission side to the MCU (240) included in the second wireless charging assembly (200), and the MCU (240) included in the second wireless charging assembly (200) can transmit information regarding the charging state of the power reception side to the MCU (140) included in the first wireless charging assembly (100).

FIG. 8 is a drawing illustrating an example of implementing a first communication module (120) or a second communication module (220) according to one embodiment of the present invention. Specifically, FIG. 8 is a drawing illustrating a first communication module (120) or a second communication module (220) implemented on a printed circuit board (PCB).

Referring to FIG. 8, the first communication module (120) (or the second communication module (220)) may be formed by extending from two terminals located at opposite ends of the four terminals arranged at the upper right of the printed circuit board (PCB). In FIG. 8, it can be understood that the portion (or pattern) formed by extending from the two terminals above represents the first communication module (120) (or the second communication module (220)).

A first power coil (110) (or a second power coil (210)) may be formed at the bottom of a printed circuit board (PCB), and the first power coil (110) (or the second power coil (210)) may be connected to two terminals located inside among the four terminals at the upper right of the PCB. Here, the first power coil (110) (or the second power coil (210)) may be formed in a coil shape, i.e., a circularly wound shape, and the first communication module (120) (or the second communication module (220)) may be formed in a different shape from the first power coil (110) (or the second power coil (210)). Specifically, the first communication module (120) (or the second communication module (220)) may be formed in an open shape toward the lower left side of the printed circuit board (PCB) and may be formed to be orthogonal to at least a portion of the first power coil (110) (or the second power coil (210)). For example, assuming that the first power coil (110) (or the second power coil (210)) is formed in a circular shape, portions (or patterns) formed to extend in the 3 o'clock direction, 6 o'clock direction, 9 o'clock direction, and 12 o'clock direction from the first communication module (120) (or the second communication module (220)) may be orthogonal to the first power coil (110) (or the second power coil (210)). Meanwhile, in addition to the corresponding portion (or pattern), there may be another portion in which the first communication module (120) (or the second communication module (220)) in FIG. 8 is orthogonal to the first power coil (110) (or the second power coil (210)).

FIG. 9 is a diagram illustrating the results of simulating the operation of a wireless charging system (10) based on the first communication module (120) and the second communication module (220) implemented as illustrated in FIG. 8. Specifically, FIG. 9 is a diagram illustrating a signal waveform measured in a first wireless charging assembly (100) including the first communication module (120) implemented as illustrated in FIG. 8.

Referring to FIG. 9, the first section (910) is a section in which the second communication module (220) transmits information related to power according to the present invention to the first communication module (120). In addition, the second section (920) is a section in which the first communication module (120) transmits information related to power according to the present invention to the second communication module (220).

The first signal waveform (930) represents a current flowing in the first power coil (110), and the frequency of the current may be 120.1 kHz and the peak to peak value may be 11.7 A _pp . In addition, the second signal waveform (940) and the third signal waveform (950) are voltages of a node that transmits information related to power in the MCU (140) (see FIG. 7) included in the first wireless charging assembly (100), and the frequency of a pulse signal used to transmit or receive the information may be 6.78 MHz, and may be set to high impedance (High-Z) when the information is not transmitted. Additionally, the fourth signal waveform (960) may be the output of a comparator (COMP) (see FIG. 7) included in the first wireless charging assembly (100), and may be the voltage of a node that receives information related to power from an MCU (140) included in the first wireless charging assembly (100).

Here, information related to power according to the present invention can be transmitted based on a pulse signal of 6.78 MHz (for example, by transmitting a high or low signal depending on the presence or absence of the pulse signal) synchronized to about 0.5 times the frequency of the current flowing in the first power coil (110), that is, 60 kHz. In addition, when receiving the information, High or Low can be determined by referring to the number of pulses appearing every 60 kHz.

Information related to power according to the present invention can be normally transmitted or received using a communication channel established between the first communication module (120) and the second communication module (220), as shown in the first signal waveform (930), the second signal waveform (940), the third signal waveform (950), and the fourth signal waveform (960).

Although the present invention has been described above with reference to specific details such as specific components and limited examples and drawings, these have been provided only to help a more general understanding of the present invention, and the present invention is not limited to the above examples, and those with common knowledge in the technical field to which the present invention pertains may make various modifications and changes based on this description.

Therefore, the idea of the present invention should not be limited to the embodiments described above, and not only the scope of the patent claims described below but also all scopes equivalent to or equivalently modified from the scope of the patent claims are included in the scope of the idea of the present invention.

10: Wireless charging system
100: 1st wireless charging assembly
110: 1st power coil
120: 1st Communication Module
200: Second wireless charging assembly
210: 2nd power coil
220: Second Communication Module

Claims (14)

A power coil for transmitting or receiving power, and
A communication module is disposed above or below the power coil and transmits or receives information related to the power based on capacitive coupling,
The above communication module is composed of two poles of symmetrical shape.
Wireless charging assembly. In the first paragraph,
The above power coil transmits or receives the power based on inductive coupling.
Wireless charging assembly. In the first paragraph,
The communication module comprises at least one outer radially open shape of the power coil and is formed to be orthogonal to at least a portion of the power coil.
Wireless charging assembly. In the third paragraph,
At least a portion of the above communication module is formed in a direction orthogonal to the central axis of the power coil.
Wireless charging assembly. In the first paragraph,
The frequency of the pulse signal used by the above communication module to transmit or receive the information is formed to a value greater than the frequency of the current flowing in the power coil.
Wireless charging assembly. In the first paragraph,
The above information is encoded or decoded by referring to the number of pulses specified in a state in which the pulse signal used by the communication module to transmit or receive the information is synchronized based on the frequency of the current flowing in the power coil.
Wireless charging assembly. In the first paragraph,
Inductors are placed in parallel at both ends of the above communication module.
Wireless charging assembly. comprising a first wireless charging assembly and a second wireless charging assembly;
The above first wireless charging assembly,
a first power coil for transmitting power, and
A first communication module is disposed above the first power coil and transmits or receives information associated with the power based on capacitive coupling,
The second wireless charging assembly,
a second power coil for receiving said power, and
A second communication module is disposed below the second power coil and transmits or receives the information based on the capacitive coupling,
The above first communication module and the above second communication module are each composed of two poles of symmetrical shape,
The two poles of the first communication module and the two poles of the second communication module are arranged to face each other.
Wireless charging system. In Article 8,
The first power coil and the second power coil transmit or receive the power based on inductive coupling.
Wireless charging system. In Article 8,
The first communication module comprises at least one outer radially open shape of the first power coil and is formed to be orthogonal to at least a portion of the first power coil,
The second communication module comprises a shape that is open in at least one outer radial direction of the second power coil and is formed to be orthogonal to at least a portion of the second power coil.
Wireless charging system. In Article 10,
At least a portion of the first communication module is formed in a direction orthogonal to the central axis of the first power coil,
At least a portion of the second communication module is formed in a direction orthogonal to the central axis of the second power coil.
Wireless charging system. In Article 8,
The frequency of the pulse signal used by the first communication module and the second communication module to transmit or receive the information is formed to a value greater than the frequency of the current flowing in the first power coil or the second power coil.
Wireless charging system. In Article 8,
The above information is encoded or decoded by referring to the number of pulses specified in a state in which the pulse signals used by the first communication module and the second communication module to transmit or receive the information are synchronized based on the frequency of the current flowing in the first power coil or the second power coil.
Wireless charging system. In Article 8,
Inductors are arranged in parallel at both ends of the first communication module and at both ends of the second communication module.
Wireless charging system.

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