Electricity storage device

Abstract

Power is recovered from a noise component generated by electrostatic induction. A power storage device includes: a first metal element electrically floating on the ground; a second metal element electrostatically coupled to the first metal element to induce a charge bias in the first metal element; and a power storage unit connected to the first metal element and the second metal element and storing a potential difference generated between the first metal element and the second metal element.

Description

Technical Field

[0001] The present technology relates to an electric storage device designed to recover electric power from noise components. Background Art

[0002] Consideration has been given to using antennas to collect electric field energy generated by the quasi-electrostatic fields or far-fields that exist around us and convert this electric field energy into electricity (energy harvesting). In the case of ambient power generation, the current flowing through the antenna and into the circuit is rectified into a DC current and converted into electrical energy. Diodes are used to rectify radio waves into DC current. Antennas equipped with a rectifying circuit are called rectennas.

[0003] The inventors of this application have proposed an energy harvester that is capable of obtaining greater received power by taking in electric field energy of a quasi-electrostatic field (near field) in addition to a wide range of radio waves, and that has a different structure from conventional energy harvesters that use a receiving antenna and convert the energy of radio waves into electricity (see Patent Document 1).

[0004] Citation List

[0005] Patent Literature

[0006] Patent Document 1: WO 2021 / 261076 A Summary of the Invention

[0007] Problems to be solved by the present invention

[0008] The device disclosed in the above-mentioned Patent Document 1 requires an antenna as a current collector and a rectifier / boosting circuit for converting an AC signal obtained by the antenna into a DC signal.

[0009] This technology relates to an energy storage device that utilizes the potential difference in an electrostatic field. This device is designed for use with electrostatic fields that do not change over time and can generate power from components that do not contain any frequency components. Consequently, it is possible to eliminate the need for a rectifier circuit (rectifier diode) required to convert frequency components into direct current. This reduces the number of components, the mounting area, and costs. This technology aims to provide an energy storage device that does not require a rectifier circuit.

[0010] Solution to the problem

[0011] This technology relates to an electric storage device, including:

[0012] a first metal element electrically floating to ground;

[0013] a second metallic element electrostatically coupled to the first metallic element to induce a charge bias in the first metallic element; and

[0014] The power storage unit is connected to the first metal element and the second metal element and stores a potential difference generated between the first metal element and the second metal element. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic diagram illustrating a schematic configuration of an embodiment of the present technology.

[0016] Figure 2 is a connection diagram of an embodiment of the present technology.

[0017] Figure 3 is a block diagram of an example of a power storage unit.

[0018] Figure 4 is a connection diagram of an example of a power storage unit.

[0019] Figure 5 is a block diagram of another example of a power storage unit.

[0020] Figure 6 This is a connection diagram of another example of the power storage unit.

[0021] Figure 7 is a connection diagram of another embodiment of the present technology.

[0022] Figure 8 is a schematic diagram for explaining the operation according to the present technology.

[0023] Figure 9 Is used to explain Figure 8 Waveform diagram.

[0024] Figure 10 is a schematic diagram for explaining the operation according to the present technology.

[0025] Figure 11 is a schematic diagram for explaining an example application of the present technology. DETAILED DESCRIPTION

[0026] The following embodiments are preferred specific examples of the present technology, and various technically preferred limitations are imposed thereon. However, unless otherwise stated in the following description, the scope of the present technology is not limited to these embodiments. In the following description, the same names and reference numerals designate the same or similar components, and any repeated explanation thereof will be omitted as appropriate.

[0027] Before describing the embodiments of this technology, we will first describe the spatial conduction of noise. Types of spatial conduction of noise include electrostatic induction, electromagnetic induction, and the radiation and reception of radio waves. This technology relates to electrostatic induction in electronic devices. Electrostatic induction is a phenomenon in which free electrons in a conductor migrate and the charge distribution is biased when a charged object (charged object) approaches the conductor. In other words, positive charge accumulates on the surface of the conductor opposite to the object in proximity, generating a positive potential.

[0028] In electronic devices, the circuit components that generate the most electrostatic induction are switching power supply circuits, including switching transistors and output rectifier diodes. These circuit components are implemented as integrated circuits (ICs) or large-scale integrated circuits (LSIs) and used, for example, in power supply boards on the primary side. Heat is dissipated to the ICs or LSIs via heat sinks.

[0029] Therefore, a large amount of electrostatic capacitance (floating capacitance) exists between the housing of a circuit component such as an LSI and the heat sink used for heat dissipation. This generates a potential difference from the ground (earth) of the electronic device due to electrostatic induction. Conventionally, a shield plate is provided between the heat sink used for heat dissipation and connected to the ground of the electronic device, with the use of a noise return circuit to return the generated charge to the ground as a countermeasure. Since the shield plate disposed between the switching transistor and the heat sink is connected to the electronic device ground, the shield plate's potential is the same as the electronic device ground, and the heat sink's potential is also the same as the electronic device ground.

[0030] This technology does not return the energy of noise generated by electrostatic induction to the ground of the electronic device, but converts the energy again into energy and utilizes the energy. Figure 1 The configuration of the embodiment is schematically illustrated.

[0031] exist Figure 1 In the present invention, an LSI 1 forming a circuit component such as a switching power supply circuit is mounted on a printed wiring board 2. LSI 1 includes a switching transistor, a coil, and the like. To dissipate heat from LSI 1, a metal heat sink 3 is provided. Insulation plates 4 and 5 and a shield plate 6 are interposed between LSI 1 and heat sink 3.

[0032] Conventionally, the shield plate 6 is electrically connected to the ground (earth) on the printed wiring board 2 so that noise generated in the LSI 1 flows to the ground. In the embodiment, the shield plate 6 is not connected to the ground but floated from the ground.

[0033] like Figure 2As shown in FIG, floating capacitance 7 exists between shield plate 6, which is floating from ground, and heat sink 3, and floating capacitance 8 exists between LSI 1 (including FET Q1, switching inductor L, resistor R, and the like as switching elements) and shield plate 6. Since LSI 1 and shield plate 6 are electrostatically coupled, charge is induced in shield plate 6 by electrostatic induction. Consequently, shield plate 6 has a potential relative to the ground of LSI 1.

[0034] As described above, the metal element (e.g., shield plate 6) in which charge is induced by electrostatic induction as a noise countermeasure is referred to as the first metal element, and the metal element (such as the ground on the electronic device side, which has voltage energy) that electrostatically couples to the first metal element and causes charge bias in the first metal element is referred to as the second metal element. The battery included in the power storage unit 11 or the capacitor included in the power storage unit 11 is charged by the potential difference generated between the first metal element (shield plate 6) and the second metal element (ground).

[0035] Shielding plate 6, serving as the first metal element, and power storage unit 11 are in contact or connected to each other via metal such as a cable, metal sheet, or pins. Similarly, the metal portion of the electronic device's housing, serving as the ground for the second metal element, and the ground for the control board, serving as the secondary board, are in contact or connected to power storage unit 11 via metal such as a cable, metal sheet, or pins. With this configuration, noise generated by a potential difference due to electrostatic induction is reused as energy by power storage unit 11. Furthermore, the noise energy is converted back into electricity, effectively reducing the noise component.

[0036] Figure 3 illustrates a schematic configuration of an example of the electric storage unit 11 (electric storage unit 11A), and Figure 4 The diagram illustrates an example circuit configuration of a power storage unit 11A. Power storage unit 11A includes a capacitor (capacitive element) 12 that stores the energy of the potential difference generated between a first metal element E1 and a second metal element E2, a protection diode 13 connected downstream of capacitor 12, a charge / discharge control IC 14, and a battery 15 serving as a secondary battery. The protection diode (Zener diode) 13 protects the charge / discharge control IC 14. The charge / discharge control IC 14 controls the charging and discharging of the battery 15. A load 16 is connected to the battery 15. The charge / discharge control IC 14 controls the charging and discharging of the battery 15, using a configuration appropriately selected from among buck-type and boost-type circuits, depending on the amount of power that can be collected. For example, the battery 15 is charged using constant-voltage charging.

[0037] Figure 5 illustrates a schematic configuration of another example of the power storage unit 11 (power storage unit 11B), and Figure 6The diagram illustrates an example circuit configuration of a power storage unit 11B. The power storage unit 11B includes a capacitor 22 that stores energy resulting from a potential difference between a first metal element E1 and a second metal element E2; a protective diode (Zener diode) 23 connected to a downstream side of the capacitor 22; a voltage detection IC 24; a capacitor 25 that stores energy similarly to the capacitor 22; and a field-effect transistor (FET) 26 serving as a switching element. A load 27 is connected to the output terminal of the FET 26.

[0038] The drain and source of a field-effect transistor (FET) 26 are inserted between one end of the capacitor 25 and a load 27. The detection output of the voltage detection IC 24 is supplied to the gate of the FET 26, thereby controlling the on / off state of the FET 26. When the voltage detection IC 24 detects that the terminal voltage of the capacitor 25 has reached a predetermined voltage, it turns on the FET 26, and power is supplied to the load 27 through the FET 26.

[0039] Figure 7 Another embodiment of the present technology is illustrated. In the above embodiment, the present technology is applied to a case where anti-noise measures are taken. On the other hand, another embodiment is one in which the shielding plate 6 serving as an anti-noise measure is not provided. That is, a metal heat sink 3 for heat dissipation is used as the first metal element, and the storage unit 11 is directly connected to the heat sink 3. The second metal element is a metal portion of the housing of the electronic device, which is the ground of the electronic device, or the ground of the control board as a secondary circuit board, as in the embodiment. According to another embodiment, it is possible to generate electricity and reduce noise by converting noise generated by electrostatic induction into electricity through the storage unit 11.

[0040] Figure 8 This is a schematic diagram for explaining the operation of another embodiment. LSI 1 includes a switching power supply circuit, and a positive charge is generated in the housing of LSI 1. Due to electrostatic induction, a charge bias is generated in heat sink 3, which is in contact with LSI 1. Negative (-) charge accumulates on the side of heat sink 3 closest to LSI 1, while positive (+) charge accumulates on the other side, generating a positive (+) potential. Accordingly, a voltmeter 31 is inserted between the ground of LSI 1 (such as a metal chassis) and heat sink 3 to detect the resulting voltage.

[0041] like Figure 9 As shown in B, the output generated by the switching power supply of LSI 1 is obtained by superimposing ripple noise on Figure 9 The ideal DC voltage shown in A is obtained. Figure 9 The circled portion C in B is magnified and Figure 9 Shown in C. Figure 9 The circled portion D in C is magnified and Figure 9 As shown in D. Figure 9 As shown in D, the ripple noise in the switching cycle has spike noise. Therefore, noise of various frequency components is radiated from the LSI 1 and is transmitted to the radiator 3 by electrostatic induction and electromagnetic induction, and noise of various frequency components is also radiated from the radiator 3.

[0042] In addition, in order to verify the effect of this technology, this technology was applied to Figure 10 The television receiver shown in FIG. Specifically, a power supply circuit 32 including a converter is mounted on a printed circuit board 33, and a heat sink 30 is provided for the power supply circuit 32, serving as a first metal element. Furthermore, a ground electrode 36 of a printed circuit board 35 on which a control circuit 34 is mounted serves as a second metal element. Ground electrode 36 is connected to a metal chassis 37 disposed on the back side of the television receiver's display panel (such as a liquid crystal display).

[0043] The heat sink 30 (first metal element) and the ground electrode 36 (second metal element) are connected to a voltmeter 31 via a cable. In this configuration, the voltmeter 31 detects the voltage change between when the TV receiver is in standby mode and when it is powered on by measuring the change in DC voltage. This confirms the potential difference induced between the first and second metal elements. For example, the voltmeter 31 indicates 6V when the TV receiver is in standby mode, but 13V when it is powered on. This allows sufficient power to be collected from the energy generated by electrostatic induction, which is part of the noise component of the heat sink.

[0044] As described above, this technology has confirmed that sufficient power can be recovered. Furthermore, this technology allows power to be recovered even during standby mode. For example, depending on the model used, this verification has shown that it is possible to obtain power equivalent to 30 minutes of standby power for a television receiver over a single day, and that standby power consumption can be reduced by using this recovered power. Furthermore, since the output voltage of the power storage unit changes between the standby and energized states, the operating status of the electronic device (television receiver) can be detected based on this voltage change.

[0045] Figure 11The diagram illustrates an example application of this technology to a television receiver. In the case of a television receiver, the television receiver is a flat-panel display, and a plate-shaped metal chassis 37 is provided on the back surface of a display panel, such as a liquid crystal display. A power supply board 33 and a control board 35 are attached to the metal chassis 37. The power supply board 33 is a printed circuit board on which switching elements and circuit components are mounted, and the control board 35 is a printed circuit board on which circuit components other than the power supply circuit, such as those for signal processing, are mounted. It has been confirmed that the heat sink 30 of the power supply board 33 is in a floating potential state in the television receiver, and there is a large potential difference with respect to the ground of the metal chassis 37 and the control board 35. For example, a DC voltage of, for example, 2.39V is generated in the metal chassis 37. Therefore, a configuration can be considered in which the metal chassis 37 serves as the first metal element, and the ground electrode 36 of the printed circuit board 35, on which the control circuit 34 is mounted, serves as the second metal element.

[0046] For electronic devices such as television receivers, each country has safety standards, such as the UL (Underwriters Laboratories Inc.) standard in the United States. In consideration of the safety defined in the safety standards, when it is necessary to maintain a certain distance from the power supply board (primary side), it is effective to adopt a configuration in which the grounded metal floating and storage unit 42 from the radiator 30 is not directly connected, but is maintained at a predetermined distance from the printed circuit board 33, as shown in FIG. Figure 11 As shown in . That is, instead of directly connecting the radiator 30 and the storage unit 42, a thin metal sheet 43 is installed in a place where the radiator 30 is likely to cause electrostatic induction (such as the resin housing 41), and the metal sheet 43 is connected to the storage unit 42 as a first metal element. As the second metal element, the ground electrode 36 is used. As the metal sheet 43, a material such as copper or aluminum is used. In addition, in addition to the resin housing 41, a metal structure can be the first metal element, and a metal sheet, cable, etc. can be connected or contacted therewith for connection. As the storage unit 42, a component that stores electricity recovered in a battery as described above, or a component that stores electricity recovered in a capacitor can be used.

[0047] While this embodiment uses electrostatic induction within the device to collect electricity from a heat sink, it is also possible to use a metal part of the electronic device induced by electrostatic induction and a ground for collection. For example, it is possible to collect electricity between the ground and a metal part of a television receiver that is electrically floating from the ground. In this case, by using the painted metal surface of the television receiver as the first metal element and the ground as the second metal element, there is no need to take measures to prevent leakage, so this embodiment can be adopted.

[0048] By using such a floating metal, the present embodiment can be applied not only to television receivers but also to other devices.

[0049] Note that this technology can be applied not only to television receivers but also to vending machines, refrigerators, washing machines, dryers, microwave ovens, game consoles, in-vehicle electronic circuits, air conditioners, various measuring instruments, factory robots, electronic equipment such as server equipment, unmanned aerial vehicles (drones), etc.

[0050] The present technology described above can provide a compact and low-cost power storage device that does not require a rectifier circuit or antenna, unlike configurations that recover power by rectifying noise components generated by electromagnetic induction or received radio waves. Note that a collector having a rectifier circuit and antenna can be used in combination with the power storage device according to this technology.

[0051] This power generation device converts electromagnetic noise generated by electronic devices into electrical energy, which can be used to power electronic devices and their peripherals, achieving efficient energy utilization. Consequently, this device can be used to address Goal 7 of the Sustainable Development Goals (SDGs), "Affordable and Clean Energy," adopted at the 2015 United Nations Summit.

[0052] While the embodiments of the present technology have been specifically described above, the present technology is not limited to the above embodiments, and various modifications can be made based on the technical concept of the present technology. In addition, one or more of any selected modification modes can be appropriately combined. In addition, without departing from the main purpose of the present technology, the configurations, methods, steps, shapes, materials, numerical values, etc. of the above embodiments can be combined with each other. For example, power generation using the present technology can be combined with natural energy sources (e.g., solar power generation and thermoelectric conversion elements) to store energy.

[0053] Note that the present technology can also have the following configurations.

[0054] (1) An electric storage device comprising:

[0055] a first metal element electrically floating on ground;

[0056] a second metallic element electrostatically coupled to the first metallic element to induce a charge bias in the first metallic element; and

[0057] The power storage unit is connected to the first metal element and the second metal element and stores a potential difference generated between the first metal element and the second metal element.

[0058] (2) The power storage device according to (1), wherein the first metal element is a metal member disposed in contact with or close to a circuit component mounted on a printed circuit board.

[0059] (3) The power storage device according to (2), wherein the circuit component is a switching power supply circuit.

[0060] (4) The power storage device according to any one of (1) to (3), wherein the first metal element is a metal located away from a printed circuit board on which the circuit component is mounted.

[0061] (5) The power storage device according to any one of (1) to (3), wherein a metal sheet, a cable, or a metal structure is provided between the first metal element and the power storage unit for connection.

[0062] (6) The power storage device according to any one of (1) to (3), wherein the power storage unit includes a capacitor or a battery for storing electric charge obtained from the obtained potential difference.

[0063] (7) The power storage device according to (6), further comprising:

[0064] a voltage detection device that detects a voltage of the capacitor; and

[0065] A switch is inserted between the capacitor and the load and is turned on or off by a signal from a voltage detection device according to the charge state of the capacitor.

[0066] (8) The power storage device according to (7), wherein a Zener diode for protecting the voltage detection device is provided at a preceding stage of the voltage detection device.

[0067] (9) The power storage device according to (6), further comprising a charge and discharge control circuit for performing constant voltage charging on the battery.

[0068] (10) The power storage device according to (9), wherein a Zener diode for protecting the charge and discharge control circuit is provided at a preceding stage of the charge and discharge control circuit.

[0069] Reference Signs List

[0070] 1LSI

[0071] 3 Radiator

[0072] 6 shielding plates

[0073] 7.8 Electrostatic Capacitance

[0074] 11, 11A, 11B power storage units

[0075] 14 Charge / discharge control IC

[0076] 15 battery

[0077] 24 voltage detection IC

[0078] 25 capacitors

[0079] E1 first metal element

[0080] E2 second metal element

Claims

1. An electric storage device comprising: a first metal element electrically floating on ground; a second metallic element electrostatically coupled to the first metallic element to induce a charge bias in the first metallic element; as well as The power storage unit is connected to the first metal element and the second metal element and stores a potential difference generated between the first metal element and the second metal element. 2 . The power storage device according to claim 1 , wherein the first metal element is a metal member disposed in contact with or close to a circuit component mounted on a printed circuit board.

3. The power storage device according to claim 2, wherein the circuit component is a switching power supply circuit. 4 . The power storage device according to claim 1 , wherein the first metal element is a metal located away from a printed circuit board on which the circuit component is mounted. 5 . The power storage device according to claim 1 , wherein a metal sheet, a cable, or a metal structure is provided between the first metal element and the power storage cell for connection. 6 . The power storage device according to claim 1 , wherein the power storage unit includes a capacitor or a battery for storing electric charge obtained from the obtained potential difference.

7. The power storage device according to claim 6, further comprising: a voltage detection device that detects a voltage of the capacitor; as well as A switch is inserted between the capacitor and the load and is turned on and off by a signal from a voltage detection device according to the charge state of the capacitor. 8 . The power storage device according to claim 7 , wherein a Zener diode for protecting the voltage detection device is provided at a preceding stage of the voltage detection device.

9. The power storage device according to claim 6, wherein a charge and discharge control circuit for performing constant voltage charging on the battery is provided. 10 . The power storage device according to claim 9 , wherein a Zener diode for protecting the charge and discharge control circuit is provided at a preceding stage of the charge and discharge control circuit.

Images