Power transmission equipment

Abstract

To provide a power transmission device that can supply power with high efficiency. [Solution] The power transmission device 1 is generally configured to include a power transmission unit 12 that transmits a power transmission signal S1 for charging the power recipient 5 by contactless power supply based on a first power P1 output from a first power source 2, and a communication unit 13 that transmits a search signal S2 for searching for the power recipient 5 based on a second power P2 output from a second power source 3 different from the first power source 2, and also receives an output signal output from the power recipient 5.

Description

Technical Field

[0001] The present invention relates to a power transmission device.

Background Art

[0002] As a conventional technique, there is known a wireless power supply reuse system including a power transmitter having a power transmission antenna that transmits power transmission electromagnetic waves connected to a power source, and a power receiver having a first power reception antenna that receives electromagnetic waves (see, for example, Patent Document 1).

[0003] This wireless power supply reuse system has a communication function with a power receiver, for example, to detect the position of the power receiver, detect the required amount of electric power, and transmit the required amount efficiently when necessary at the required position.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a conventional wireless power supply reuse system, since a signal for detecting the position of a power receiver and power transmission electromagnetic waves are output based on the power of the same power source, the efficiency of power supply by the power transmission electromagnetic waves decreases.

[0006] Therefore, an object of the present invention is to provide a power transmission device capable of performing power supply with high efficiency.

Means for Solving the Problems

[0007] One aspect of the present invention provides a power transmission device comprising: a power transmission unit that transmits a power transmission signal for charging a power receiving object by contactless power supply based on a first power output from a first power source; and a communication unit that transmits a search signal for searching for a power receiving object based on a second power output from a second power source different from the first power source, and also receives an output signal output from the power receiving object. [Effects of the Invention]

[0008] According to the present invention, power can be supplied with high efficiency. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a block diagram showing an example of a power transmission system including a power transmission device according to the first embodiment. [Figure 2] Figure 2 is a block diagram showing an example of a power transmission system including a power transmission device according to the second embodiment. [Figure 3] Figure 3 is a block diagram showing an example of a power transmission system including a power transmission device according to the third embodiment. [Modes for carrying out the invention]

[0010] (Summary of the embodiment) The power transmission device according to this embodiment is generally configured to include a power transmission unit that transmits a power transmission signal for charging a power receiving object by contactless power supply based on a first power output from a first power source, and a communication unit that transmits a search signal for searching for a power receiving object based on a second power output from a second power source different from the first power source, and also receives an output signal output from the power receiving object.

[0011] This power transmission device transmits power transmission signals and search signals using power from different power sources, allowing for more efficient power supply compared to using power from a single power source.

[0012] [First Embodiment] (Overview of power transmission device 1) Figure 1 is a block diagram showing an example of a power transmission system including a power transmission device according to the first embodiment. In Figure 1, and in Figures 2 and 3 described later, the main signals and information flows are indicated by arrows. Furthermore, the numerical range "A~B" is used to mean A or greater and B or less. Below, an overview of the power transmission device 1 will be described.

[0013] As shown in Figure 1, the power transmission system 9 is generally configured to include a power transmission device 1, a first power supply 2, a second power supply 3, a drive voltage circuit 4, and a power receiving device 5. The power transmission system 9 is configured so that the power receiving device 5 is charged without the user's awareness when it receives a power transmission signal S1 transmitted from the power transmission device 1. The power receiving device 5 is, for example, an electronic device such as a smartphone, tablet terminal, personal computer, drone, remote controller, mobile battery, and electronic key, but is not limited to these. Furthermore, there may be one power receiving device 5 or multiple devices.

[0014] As shown in Figure 1, the power transmission device 1 is generally configured to include a power transmission unit 12 that transmits a power transmission signal S1 for charging the power recipient 5 by contactless power supply based on a first power P1 output from a first power source 2, and a communication unit 13 that transmits a search signal S2 for searching for the power recipient 5 based on a second power P2 output from a second power source 3 different from the first power source 2, and also receives a beacon signal S4 as an output signal output from the power recipient 5.

[0015] The communication unit 13 communicates with the power recipient 5 based on the second power P2 output from the second power source 3 which utilizes renewable energy.

[0016] The communication unit 13 transmits a search signal S2 based on a second power P2 output from a photovoltaic element that converts light energy, which is a renewable energy source, into electrical energy.

[0017] The communication unit 13 transmits a search signal S2 based on the second power P2 output from the perovskite solar cell as the photovoltaic element. That is, the second power source 3 is a perovskite solar cell. As shown in FIG. 1, the second power source 3 is electrically connected to the drive voltage circuit 4.

[0018] Furthermore, as shown in FIG. 1, the power transmission device 1 includes a first input unit 10, a second input unit 11, a control unit 14, and a communication antenna 15.

[0019] (Configuration of the first power source 2) The first power source 2 is at least one power source such as, for example, a household power source, a battery, and a power source that converts renewable energy into electric power. The first power source 2 is a different power source from the second power source 3. When the power transmission device 1 is mounted on a vehicle, the battery is the vehicle battery.

[0020] (Configuration of the second power source 3) As described above, the second power source 3 outputs the second power P2 based on renewable energy, but is not limited thereto, and may be any power source as long as it is not the same as the first power source 2. Therefore, even if it has the same type as the first power source 2, it is acceptable.

[0021] As shown in FIG. 1, the second power P2 is input to the drive voltage circuit 4. The drive voltage circuit 4 converts the second power P2 from DC to AC, and further adjusts the voltage to generate a drive voltage V for driving the communication unit 13. As a modification, the drive voltage circuit 4 may be connected between the second input unit 11 of the power transmission device 1 and the communication unit 13, or the communication unit 13 may be configured to have a similar function. That is, the power transmission device 1 may be configured to have the function of the drive voltage circuit 4.

[0022] Renewable energy is, for example, energy based on wind power, light, geothermal heat, etc. The second power source 3 of the present embodiment is a perovskite solar cell. This perovskite solar cell has flexibility and can generate electricity with a small amount of light, so it can be arranged not only outdoors but also indoors and inside a vehicle.

[0023] (Configuration of the first input unit 10) The first input unit 10 has an input terminal that can be connected to the first power supply 2 and is configured to receive the first power P1 output from the first power supply 2. The first input unit 10 outputs the input first power P1 to the power transmission unit 12.

[0024] (Configuration of the second input unit 11) The second input unit 11 has an input terminal that can be connected to the drive voltage circuit 4 and is configured to receive a drive voltage V based on the second power P2 output from the second power supply 3. The second input unit 11 outputs the input drive voltage V to the communication unit 13. As a modified example, if the communication unit 13 has the function of the drive voltage circuit 4, the second input unit 11 has an input terminal that can be connected to the second power supply 3 and is configured to receive the second power P2 output from the second power supply 3.

[0025] (Configuration of the power transmission unit 12) The power transmission unit 12 is driven based on a first power P1 input via the first input unit 10 and generates a power transmission signal S1. This power transmission signal S1 is output as microwaves to the power receiving target 5 via the communication antenna 15. The power transmission signal S1 has a frequency of 900 MHz to 60 GHz, for example, but is not limited to this. The communication antenna 15 may be one or multiple. Furthermore, the communication antenna 15 may be configured as separate antennas for the power transmission unit 12 and the communication unit 13.

[0026] (Composition of Communications Unit 13) The communication unit 13 is driven based on a second power P2 input via the second input unit 11 and outputs a search signal S2 and charging schedule information S3.

[0027] The search signal S2 is output to locate the power receiving device 5. The power receiving device 5 periodically outputs a beacon signal S4, but also outputs a beacon signal S4 based on the reception of the search signal S2. The search signal S2 is always output to transmit the power transmission signal S1 to multiple power receiving devices 5. The power transmission device 1 does not use the power of the first power supply 2 to output the search signal S2, and therefore does not consume the power of the first power supply 2.

[0028] The communication unit 13 outputs charging schedule information S3 when, for example, the power receiving device 5 enters the range of the power transmission signal S1. This charging schedule information S3 is output as charging-related information such as microwave frequency and voltage after receiving the beacon signal S4. The power receiving device 5 performs charging processing based on the charging schedule information S3.

[0029] (Configuration of the control unit 14) The control unit 14 is a microcomputer composed of, for example, a CPU (Central Processing Unit) that performs calculations and processing on acquired data according to a stored program, and semiconductor memories such as RAM (Random Access Memory) and ROM (Read Only Memory). The control unit 14 comprehensively controls the power transmission unit 12 and the communication unit 13.

[0030] (Operation of power transmission device 1) The control unit 14 of the power transmission device 1 controls the communication unit 13 to output a search signal S2 from the communication antenna 15 using the drive voltage V based on the second power P2 of the second power supply 3.

[0031] When the control unit 14 receives the beacon signal S4 output from the power receiving device 5, it controls the communication unit 13 to output charging schedule information S3 to the power receiving device 5.

[0032] When the control unit 14 receives a beacon signal S4 output from the powered device 5 that has received the charging schedule information S3, it controls the power transmission unit 12 based on the received beacon signal S4 and transmits a power transmission signal S1 generated based on the first power P1 of the first power supply 2 from the communication antenna 15 towards the powered device 5. This power transmission signal S1 is transmitted until it receives a beacon signal S4 from the powered device 5 indicating that transmission has stopped, or until the powered device 5 moves out of the range of the power transmission signal S1. While transmitting the power transmission signal S1, the control unit 14 also controls the communication unit 13 to output a search signal S2 from the communication antenna 15 in order to search for other powered devices 5.

[0033] (Effects of the first embodiment) The power transmission device 1 according to this embodiment can supply power with high efficiency. Specifically, the power transmission device 1 drives the power transmission unit 12 based on the first power P1 of the first power source 2, and drives the communication unit 13 based on the second power P2 of the second power source 3, which is different from the first power source 2. Therefore, compared to the case where the power transmission unit and the communication unit are driven by the same power source, the power transmission device 1 converts almost all of the first power P1 into a power transmission signal S1 and transmits it to the power recipient 5, thus enabling high-efficiency power supply.

[0034] Since the power transmission device 1 drives the power transmission unit 12 based on the first power P1 and the communication unit 13 based on the second power P2, there is no power loss due to splitting the first power P1 between the power transmission unit 12 and the communication unit 13, compared to the case where the power transmission unit and the communication unit are driven by the same power source.

[0035] Since the power transmission device 1 uses renewable energy as its second power source 3, it can reduce household power consumption compared to a configuration that does not employ this setup.

[0036] Because the second power source 3 of the power transmission device 1 is a perovskite solar cell, it can generate electricity even from indoor lighting, unlike other solar cells, and the power transmission system 9 can be operated indoors. Furthermore, because the perovskite solar cell of the power transmission device 1 is more flexible than other solar cells, it can be easily placed in available space indoors and utilized effectively, offering a high degree of freedom in placement.

[0037] Conventional power transmission devices constantly output signals to search for receiving devices, resulting in high power consumption. However, the power transmission device 1 of this embodiment outputs the search signal S2 using a second power source 3 that utilizes renewable energy. Therefore, compared to the case where a single power source is used to constantly output a search signal, it does not consume power from the first power source 2 to output the search signal S2.

[0038] As a variation, in the power-saving mode in which the power transmission device 1 is driven with the minimum power, the second power P2 of the second power supply 3 may be configured to supply power not only to the communication unit 13 but also to the control unit 14 and other components that are driven during the power-saving mode.

[0039] [Second Embodiment] The second embodiment differs from the first embodiment in that, when the power generated by the second power supply is low, the communication unit is temporarily driven by the first power supply.

[0040] Figure 2 is a block diagram showing an example of a power transmission system including a power transmission device according to the second embodiment. In the embodiments described below, parts having the same function and configuration as those in the first embodiment are denoted by the same reference numerals as in the first embodiment, and their descriptions are omitted.

[0041] As shown in Figure 2, the power transmission device 1 is generally configured to include a switching unit 16 that switches the electrical connection between the first power supply 2 and the power transmission unit 12 and the communication unit 13, and a control unit 14 that controls the switching unit 16 and electrically connects the first power supply 2 and the communication unit 13 when the second power P2 is lower than a predetermined threshold 140.

[0042] Furthermore, as an example, the power transmission device 1 includes a drive voltage circuit 4 between the switching unit 16 and the communication unit 13, as shown in Figure 2.

[0043] The control unit 14 of the power transmission device 1 electrically connects the first power supply 2 and the power transmission unit 12, and also electrically connects the second power supply 3 and the communication unit 13, when the second power P2 is greater than or equal to a threshold value of 140. The second power P2 is converted into a drive voltage V in the drive voltage circuit 4 and output to the communication unit 13.

[0044] Furthermore, the control unit 14 of the power transmission device 1 electrically connects the first power supply 2 and the communication unit 13 when the second power P2 is less than the threshold value 140. The first power P1 is converted into a drive voltage V in the drive voltage circuit 4 and output to the communication unit 13. This connection is temporary, and when the second power P2 becomes equal to or greater than the threshold value 140, an electrical connection is made between the first power supply 2 and the power transmission unit 12, and between the second power supply 3 and the communication unit 13.

[0045] When the second power P2 is less than the threshold 140, the control unit 14 electrically connects the first power supply 2 and the power transmission unit 12, for example, while outputting the power transmission signal S1, and electrically connects the first power supply 2 and the communication unit 13 while searching for the power recipient 5. The control unit 14 may also periodically switch the electrical connections between the first power supply 2 and the power transmission unit 12 and the communication unit 13, for example, when the second power P2 is less than the threshold 140.

[0046] (Effects of the second embodiment) In this embodiment, if the amount of power generated is low due to reasons such as the room being dark, and the second power P2 drops to the point where it cannot drive the communication unit 13, the power transmission device 1 can temporarily connect the first power source 2 and the communication unit 13 by the switching unit 16 until the amount of power generated recovers, and continue searching for the power recipient 5.

[0047] [Third Embodiment] The third embodiment differs from the other embodiments in that the power transmission device includes a rechargeable battery.

[0048] Figure 3 is a block diagram showing an example of a power transmission system including a power transmission device according to the third embodiment.

[0049] The power transmission device 1 of this embodiment includes, for example, a charging circuit 17 and a rechargeable battery 18, as shown in Figure 3. The charging circuit 17 is a circuit that controls the charging of the rechargeable battery 18 using the input second power P2. The rechargeable battery 18 is charged by the charging circuit 17 and outputs a drive voltage V based on the charged power to the communication unit 13.

[0050] The rechargeable battery 18 is, for example, a secondary battery such as a lithium-ion battery, a nickel-metal hydride battery, or a nickel-cadmium battery. The charging circuit 17 and the rechargeable battery 18 are configured to supply a drive voltage V to the communication unit 13 while charging. The charging circuit 17 and the rechargeable battery 18 are also configured to supply a drive voltage V to the communication unit 13 when fully charged. The rechargeable battery 18 may also be, for example, a capacitor that can store a large amount of charge. Furthermore, since the rechargeable battery 18 supplies the drive voltage V when the power generation amount of the second power supply 3 is small, a rechargeable battery with a small charging capacity and low cost can be used.

[0051] (Effects of the third embodiment) In this embodiment, the power transmission device 1 charges the rechargeable battery 18 with the second power supply 3 and drives the communication unit 13 with the drive voltage V of the rechargeable battery 18. Therefore, compared to a configuration that is not adopted, even if the power generation amount of the second power supply 3 is small and it is not possible to generate the drive voltage V, the communication unit 13 can be stably driven using the power of the rechargeable battery 18.

[0052] According to the power transmission device 1 of at least one embodiment described above, it becomes possible to supply power with high efficiency.

[0053] The power transmission device 1 according to the above-described embodiments and modifications may, for example, be partially implemented by a computer program, an ASIC (Application Specific Integrated Circuit), and an FPGA (Field Programmable Gate Array), depending on the application.

[0054] Although several embodiments and modifications of the present invention have been described above, these embodiments and modifications are merely examples and do not limit the invention as defined in the claims. These novel embodiments and modifications can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. Furthermore, not all combinations of features described in these embodiments and modifications are necessarily essential for solving the problem of the invention. Moreover, these embodiments and modifications are included in the scope and spirit of the invention, as well as in the invention described in the claims and its equivalents. [Explanation of symbols]

[0055] 1...Power transmission device, 2...First power supply, 3...Second power supply, 4...Drive voltage circuit, 5...Power receiving target, 9...Power transmission system, 10...First input unit, 11...Second input unit, 12...Power transmission unit, 13...Communication unit, 14...Control unit, 15...Communication antenna, 16...Switching unit, 17...Charging circuit, 18...Rechargeable battery, 140...Threshold, P1...First power, P2...Second power, S1...Power transmission signal, S2...Search signal, S3...Charging schedule information, S4...Beacon signal, V...Drive voltage

Claims

1. A power transmission unit that transmits a power transmission signal for charging a powered object via contactless power supply based on a first power output from a first power source, A communication unit that transmits a search signal for searching for the powered object based on a second power output from a second power source different from the first power source, and receives an output signal output from the powered object, A suitable power transmission device.

2. The communication unit communicates with the power recipient based on the second power output from the second power source which utilizes renewable energy. The power transmission device according to claim 1.

3. The communication unit transmits the search signal based on the second power output from the photovoltaic element that converts the renewable energy, which is light energy, into electrical energy. The power transmission device according to claim 2.

4. The communication unit transmits the search signal based on the second power output from the perovskite solar cell, which is the photovoltaic element. The power transmission device according to claim 3.

5. Furthermore, a switching unit that switches the electrical connection between the first power supply, the power transmission unit, and the communication unit, A control unit that controls the switching unit and electrically connects the first power supply and the communication unit when the second power is lower than a predetermined threshold, Equipped with, A power transmission device according to any one of claims 1 to 4.

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