JP2017212849A - Power transmitter and power receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply appropriate power to an electronic device by improving efficiency of power supply.SOLUTION: A power transmitter 20 supplies a micro wave to a power receiver 40 for converting the received micro wave to DC voltage to supply power to an electronic device. The power transmitter 20 includes: a plurality of power transmission units for transmitting a micro wave to the power receiver 40; and a controller 22 for controlling the power transmission units. Each power transmission unit includes an antenna 26 for transmitting power and receiving a beacon signal transmitted from the power receiver 40; and a transceiver 23 that on the basis of a phase control signal, adjusts a phase of a micro wave to be transmitted to the power receiver 40 and, on the basis of an amplification control signal, adjusts the degree of amplification of the microwave to output the micro wave. A control unit, on the basis of a phase difference and amplification difference between a reference signal and the beacon signal, generates the phase control signal and the amplification control signal, respectively.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power transmission device and a power reception device, and more particularly to a technique effective for wireless power feeding to an electronic device.

  In recent years, as a power supply technique, for example, so-called wireless power supply that supplies power in a contactless manner without using a power cable or the like for an electronic device or the like is becoming popular. As this type of wireless power supply technology, for example, a technology for supplying electric power to an electronic device by using micro energy is known (see, for example, Patent Document 1).

  In the technique of Patent Document 1, the microwave energy is concentrated and charged at a position that responds to reception of a beacon signal from a beacon device by a power transmitter having one or more adaptive phase microwave array emitters. The rectenna in the device describes that the microwave energy is rectified and used for main power.

Japanese Patent Application Laid-Open No. 2014-2223018

  In the technique of Patent Document 1 described above, the reflection of a wall or the like is also used, so that power can be propagated even if there is an obstacle such as a human in the line-of-sight propagation path of the power transmitter that transmits microwaves. However, when the reflection of the wall or the like is used, there is a problem that the attenuation of the power transmission signal is increased and the power supply efficiency is lowered.

  As a result, the electronic device may be charged for a long time, or power may be insufficient to cause a malfunction of the electronic device.

  The objective of this invention is providing the technique which can supply the optimal electric power to an electronic device by improving the efficiency of an electric power supply.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  That is, a typical power transmission device transmits a microwave to a power reception device that supplies power to an electronic device. This power transmission device has a plurality of power transmission units and a control unit. The power transmission unit transmits microwaves to the power receiving device. The control unit controls the power transmission unit.

  The plurality of power transmission units each have an antenna and a microwave output unit. The antenna receives a beacon signal having the same frequency as the microwave transmitted from the power transmission and power reception device. The microwave output unit adjusts the phase of the microwave transmitted to the power receiving device based on the phase control signal, and adjusts and outputs the amplification degree of the microwave based on the amplification control signal.

  The control unit generates a phase control signal based on the phase difference between the reference signal and the beacon signal, and generates an amplification control signal based on the amplitude difference between the reference signal and the beacon signal.

  The microwave output unit has a signal detection unit, a phase adjustment unit, and a gain adjustment amplification unit. The signal detection unit detects an amplitude difference and a phase difference between the beacon signal received by the antenna and the reference signal. The phase adjustment unit adjusts the phase of the microwave transmitted to the power receiving device based on the phase control signal. The gain adjustment amplification unit adjusts the amplification degree of the microwave transmitted to the power receiving device based on the amplification control signal.

  In particular, the control unit calculates the sum of the received power transmitted from the power receiving apparatus, determines whether the sum of the received power is larger than a preset expected power value, and the sum of the received power is the expected power value. If below, generate either phase control signal or amplification control signal so that the total received power is larger than the expected power value, and either microwave phase shift amount or microwave amplification degree Adjust one.

  Here, in the embodiment, it is described as a microwave that is a typical frequency, but the present invention is a radio wave of UHF (300 MHz) band or higher, particularly a quasi-microwave (920 MHz band) to a millimeter wave (30 GHz or higher). The band is technically applicable.

  According to the one embodiment, the charging efficiency can be improved.

3 is an explanatory diagram illustrating an example of a configuration in a wireless power feeding system according to Embodiment 1. FIG. FIG. 2 is an explanatory diagram illustrating an example of a configuration of a power receiver included in the wireless power feeding system of FIG. 1. 2 is a flowchart illustrating an example of initial setting when power is supplied by microwaves in the wireless power supply system of FIG. 1. 4 is a flowchart showing an example of a speaker selection process of FIG. 1 executed after the initial setting of FIG. 3 is completed. 3 is a flowchart illustrating an example of power adjustment processing by the wireless power feeding system of FIG. 1. It is explanatory drawing which shows an example at the time of applying the wireless electric power feeding system of FIG. 1 to an electronic device. It is explanatory drawing which shows an example of a structure in the LED fluorescent lamp which the lighting fixture of FIG. 6 has. It is sectional drawing for demonstrating the specific example in the lighting fixture by Embodiment 2. FIG. It is the whole view which looked at the ceiling side from the floor side for demonstrating the specific example in the lighting fixture by Embodiment 2. FIG. FIG. 10 is an explanatory diagram illustrating an example of a configuration in a wireless power feeding system according to a third embodiment. 10 is an explanatory diagram illustrating an example of a configuration of a power receiver included in a wireless power feeding system according to a fourth embodiment. FIG. FIG. 10 is an explanatory diagram illustrating an example of a configuration in a wireless power feeding system for a mobile terminal according to a fifth embodiment.

  In the following embodiments, when it is necessary for the sake of convenience, the description will be divided into a plurality of sections or embodiments. However, unless otherwise specified, they are not irrelevant to each other. There are some or all of the modifications, details, supplementary explanations, and the like.

  Further, in the following embodiments, when referring to the number of elements (including the number, numerical value, quantity, range, etc.), especially when clearly indicated and when clearly limited to a specific number in principle, etc. Except, it is not limited to the specific number, and may be more or less than the specific number.

  Further, in the following embodiments, the constituent elements (including element steps and the like) are not necessarily indispensable unless otherwise specified and apparently essential in principle. Needless to say.

  Similarly, in the following embodiments, when referring to the shape, positional relationship, etc. of components, etc., the shape of the component is substantially the case unless it is clearly specified and the case where it is clearly not apparent in principle. And the like are included. The same applies to the above numerical values and ranges.

  In all the drawings for explaining the embodiments, the same members are denoted by the same reference symbols in principle, and the repeated explanation thereof is omitted.

(Embodiment 1)
<Configuration example of wireless power supply system>
FIG. 1 is an explanatory diagram illustrating an example of a configuration of the wireless power feeding system 10 according to the first embodiment.

  The wireless power supply system 10 is a system that supplies electric power in a non-contact manner using radiant energy such as microwaves.

  As shown in FIG. 1, the wireless power supply system 10 includes a power transmitter 20 and a power receiver 40. The power transmitter 20 which is a power transmission device wirelessly transmits a microwave. The power receiver 40 as a power receiving apparatus receives the microwave transmitted from the power transmitter 20 and converts it into electric power.

  Here, the power transmitter 20 is assumed to be installed at, for example, a ceiling or a high position close to the ceiling. Thereby, the probability that there is an obstacle that shields the microwave transmitted from the power transmitter 20 is reduced, and the microwave can be transmitted efficiently, that is, the power transmission efficiency can be improved.

  Further, the power receiver 40 is provided in an electronic device, and in FIG. 1, it is assumed that each of the power receivers 40 is provided in a later-described speaker 50 included in the acoustic system.

  The acoustic system is a system that reproduces three or more channels such as surround sound, and includes a reproduction device (not shown) and a plurality of speakers 50. The speaker 50 plays back content data output from the playback device. As for the number of these speakers 50, a large number of speakers are used according to the number of channels.

  Content data such as an audio signal is transmitted to each speaker 50 wirelessly such as Bluetooth (registered trademark) (not shown) from a reproduction device that reproduces content. Each of these speakers 50 is provided with an electronic circuit. The electronic circuit amplifies the content data received from the playback device, and then plays back and outputs the content data.

  The power transmitter 20 includes a communication unit 21, a controller 22, a plurality of transceivers 23, an antenna array 24, and an oscillator 25. The communication unit 21 performs bidirectional wireless communication with the power receiver 40. The controller 22 serving as a control unit controls transmission of microwaves in the power transmitter 20.

  The transceiver 23 serving as a microwave output unit adjusts the amplitude and phase of the microwave based on the control of the controller 22. The antenna array 24 has a plurality of antennas 26. The transceiver 23 and the antenna 26 constitute a transmission unit.

  Each transceiver 23 is individually connected to an antenna 26. The oscillator 25 generates a reference signal having a preset frequency. The reference signal generated by the oscillator 25 is input to each transceiver 23.

  The transceiver 23 includes an amplitude phase comparator 27, a phase shifter 28, a variable gain amplifier 29, and a switch unit 30. The amplitude / phase comparator 27, which is a signal detection unit, compares the received beacon signal with the reference signal of the oscillator 25 and outputs the comparison result to the controller 22.

  The phase shifter 28 as a phase adjustment unit adjusts the amount of phase shift in the reference signal generated by the oscillator 25 based on the phase control signal output from the controller 22. A variable gain amplifier 29 that is a gain adjustment amplification unit amplifies the reference signal generated by the oscillator 25 and outputs it as a microwave. The variable gain amplifier 29 adjusts the gain, that is, the amplification degree, based on the amplification control signal output from the controller 22.

  The switch unit 30 switches the connection destination of the antenna 26. Specifically, based on a switch control signal output from the controller 22, the antenna 26 is switched to be connected to either the output unit of the variable gain amplifier 29 or the input unit of the amplitude / phase comparator 27. The controller 22 generates a phase control signal and an amplification control signal based on the comparison result by the amplitude phase comparator 27 described above.

<Example configuration of power receiver>
Next, the configuration of the power receiver 40 will be described.

  FIG. 2 is an explanatory diagram illustrating an example of a configuration of the power receiver 40 included in the wireless power supply system 10 of FIG.

  The power receiver 40 includes a communication unit 41, a controller 42, a rectifying unit 43, a power receiving antenna 44, and a beacon 45. The communication unit 41 performs bidirectional wireless communication with the communication unit of the power transmitter 20. Here, the content data receiver is omitted.

  The power receiving antenna 44 receives the microwave transmitted from the power transmitter 20 of FIG. The rectifier 43 rectifies the microwave received by the power receiving antenna 44 to convert it into a DC voltage, and supplies it as an operating power supply for the electronic circuit included in the speaker 50 of FIG. The controller 42 controls power reception in the power receiver 40. The beacon 45 serving as a beacon unit outputs a beacon signal. Moreover, the communication part 41 and the controller 42 become a control communication part.

  In addition, as a beacon frequency and a power transmission frequency, an ISM (Industry Science Medical) band such as a 2.4 GHz band or a 5.8 GHz band is used.

  Next, a power feeding operation in the wireless power feeding system 10 will be described.

<Initial setting example>
FIG. 3 is a flowchart illustrating an example of an initial setting at the time of power feeding by microwaves in the wireless power feeding system 10 of FIG.

  First, the controller 22 of the power transmitter 20 determines whether initial setting is unnecessary (step S101). The initial setting is a process of setting the received power at the power receiver 40 to an expected value by adjusting the phase and amplification degree of the microwave transmitted from the power transmitter 20.

  For example, when the power supply is resumed after the wireless power supply is stopped, the initial setting is not necessary. On the other hand, when microwave transmission is performed by the power transmitter 20 for the first time, initial setting is required. The same initial setting is performed when the installation position of the speaker 50 is changed.

  Whether or not the initial setting is necessary is determined based on, for example, a flag stored in a memory (not shown) of the controller 22 or the like. If a flag indicating that the initial setting has been performed is stored in the memory, the controller 22 determines that the initial setting is unnecessary.

  If the initial setting is unnecessary in the process of step S101, the initial setting process ends. On the other hand, when it is determined in step S101 that initial setting is necessary, the power transmitter 20 receives a beacon signal output from the beacon 45 of the power receiver 40 in FIG. 2 (step S102).

  In the process of step S <b> 102, the controller 22 outputs a switch control signal to the switch unit 30, thereby switching the connection destination of the switch unit 30 to the input unit of the amplitude phase comparator 27.

  At this time, a beacon signal is output from the beacon 45 included in the power receiver 40, and the antenna 26 receives the beacon signal. The beacon signal received by the antenna 26 is input to the amplitude / phase comparator 27 via the switch unit 30.

  The amplitude / phase comparator 27 detects the amplitude and phase difference of the beacon signal received by the antenna 26 using the reference signal generated by the oscillator 25 as a reference, and outputs the detection result to the controller 22 (step S102).

  The controller 22 adjusts the amount of phase shift and the amplification degree of the microwave to be transmitted based on the detection result of the amplitude phase comparator 27 (step S103). Specifically, the controller 22 calculates the optimum power transmission amplitude and phase difference from the amplitude and phase difference of the beacon signal received by each antenna 26, and the amplification degree of the variable gain amplifier 29 and the phase shifter 28. Adjust the amount of phase shift.

  As described above, the phase shifter 28 adjusts the amount of phase shift based on the phase control signal output from the controller 22, and the variable gain amplifier 29 is based on the amplification control signal output from the controller 22. Amplification is adjusted.

  Thus, by providing not only the phase shifter 28 but also the variable gain amplifier 29, the gain can be adjusted for each antenna 26, so that the phase shifter 28 only adjusts the amount of phase shift. The power transmission efficiency can be further improved.

  As an example of the optimum amplitude and phase difference, the gain of the variable gain amplifier 29 is increased in the antenna 26 having a high beacon signal amplitude. As for the phase difference, it is conceivable that microwaves are transmitted with a phase that is complex conjugate with respect to the phase difference between the received beacon signal and the reference signal of the oscillator 25.

  In addition, the gain amplitude can be fed without control, but the feed efficiency can be further increased by performing the amplitude control as described above.

  When the adjustment of the phase shift amount and the amplification degree of the microwave to be transmitted is completed, power transmission is started from the power transmitter 20, and the power received by the controller 42 is measured in the power receiver 40 (step S104).

  For example, the controller 42 calculates the received power from the DC voltage converted by the rectifying unit 43. The controller 42 transmits the measured power, that is, the received power value, from the communication unit 41 to the communication unit 21 of the power transmitter 20.

  The controller 22 determines whether or not the received power value received by the communication unit 21 is equal to or less than an expected power value that is a preset threshold value (step S105). It is assumed that the expected power value is stored in, for example, a memory (not shown) included in the controller 22.

  If it is determined in step S105 that the received power of the power receiver 40 is less than or equal to the expected power value, the process returns to step S103, and the phase shift amount and the amplification degree of the microwaves to be transmitted again are readjusted. .

  As a readjustment technique, a change in received power at that time may be detected by increasing the gain of the variable gain amplifier 29 or changing the phase of the microwave. Or you may make it adjust an amplification degree and a phase, respectively.

  When increasing the amplification degree of the variable gain amplifier 29, the controller 22 does not increase the amplification degree of all the variable gain amplifiers 29 provided in each transceiver 23, but a small number, for example, about one or two variable gain amplifiers. The degree of amplification of 29 is gradually increased.

  Similarly, when changing the phase of the antenna, the controller 22 does not change the phase shift of all the microwaves, but gradually adjusts a small number of phase shifters 28, for example, about 1 or 2. By these, highly accurate adjustment can be performed.

  If the received power is larger than the expected power value in step S105, the initial setting is completed.

  When the number of power receivers 40 is large, the total received power may exceed the allowable value of the transmitted power that can be transmitted by the power transmitter 20 in the initial setting. If the allowable value of the power transmission value is exceeded, adjustment with high accuracy may not be possible. In this case, adjustment is performed by operating the power receivers 40 one by one. As a result, it is possible to perform adjustment with high accuracy and to improve power supply efficiency.

  When the transmission efficiency is significantly low, such as when the distance between the power transmitter 20 and the power receiver 40 is long, the operation of the speaker 50 with low transmission efficiency is turned off. This can prevent malfunction of the speaker 50 caused by power shortage.

  Alternatively, notification that the transmission efficiency is insufficient may be made by an alarm or the like. Thus, it is possible to notify the user in advance of insufficient power supply to the speaker 50 or the like.

  As described above, adjustment can be performed so that optimum power is supplied to each speaker 50. Thereby, the power supply shortage of the speaker 50 can be solved.

<Speaker selection processing example>
FIG. 4 is a flowchart showing an example of the selection process of the speaker 50 of FIG. 1 executed after the initial setting of FIG. 3 is completed.

  The selection process of the speaker 50 is a process for solving the shortage of the received power by stopping the low priority speaker when the received power is assumed to be insufficient. Note that the process in FIG. 4 is also executed when it is determined in step S101 in FIG. 3 that the initial setting is unnecessary.

  First, the controller 42 of the power receiver 40 of FIG. 2 transmits the output value or power consumption value of the speaker 50 of FIG. 1 having the power receiver 40 from the communication unit 41 to the communication unit 21 of the power transmitter 20 (step S201). . Here, as the power consumption value, an actual power consumption value or a rated power consumption value when the speaker is used may be used.

  The actual power consumption value of the speaker 50 is stored in a memory (not shown) of the controller 42, for example. Or you may make it store in the memory etc. which were provided in the electronic circuit which the speaker 50 has.

  The controller 22 of the power transmitter 20 determines whether or not the sum of the actual power consumption values of the respective speakers 50 received by the communication unit 21 is less than or equal to the power transmission capability of the power transmitter 20 (step S202).

  If it is determined that the power transmission capacity of the power transmitter 20 has been exceeded, the controller 22 turns off the low priority speaker based on the priority information (step S203), and then returns to the process of step S201. Therefore, the processing of steps S201 to S203 is executed until the total of the actual power consumption values of the speaker 50 becomes equal to or less than the power transmission capability of the power transmitter 20.

  Here, the priority information is information indicating a speaker to be turned off when the power transmission capacity of the power transmitter 20 is exceeded. For example, a speaker having less influence during reproduction is preferentially turned off. This priority information is also stored in the memory of the controller 22, for example.

  In the process of step S203, the controller 22 determines a speaker with a low priority based on the priority information. Subsequently, the controller 22 outputs a stop request signal to the power receiver 40 provided in the low priority speaker.

  The power receiver 40 that has received the stop request signal stops supplying power to the electronic circuit of the speaker 50. In this case, for example, a switch is provided at the output section of the rectifying section 43. This switch is controlled on / off by the controller 42.

  When the switch is turned on under the control of the controller 42, the DC voltage generated by the rectifier 43 is supplied to the electronic circuit via the switch.

  Then, when the controller 42 turns off the switch, the power supply to the electronic circuit is stopped. Even when the power supply to the electronic circuit is stopped, the controller 42, the beacon 45, the communication unit 41, and the like are supplied with the DC voltage generated by the rectifying unit 43 as the operating power.

  Alternatively, instead of stopping the power supply to the electronic circuit, a control signal for stopping the operation of the electronic circuit included in the speaker 50 may be output. In this case, power is supplied to the electronic circuit of the speaker 50, but the operation of the electronic circuit is stopped.

  If it is determined in step S202 that the total actual power consumption value of the speaker 50 does not exceed the power transmission capability of the power transmitter 20, the speaker selection process ends.

  As described above, even if the number of speakers 50 is large and the power transmission capability of the power transmitter 20 is insufficient, the shortage of the power transmission capability of the power transmitter 20 is solved while reducing the effect of regeneration due to the decrease in the number of speakers. Can do.

  In FIG. 4, in the process of step S <b> 202, an example has been described in which it is determined whether or not the total of the actual power consumption values of the speakers 50 received by the communication unit 21 is equal to or less than the power transmission capability of the power transmitter 20. However, for example, the output value of each speaker may be used instead of the power consumption value.

  In this case, the controller 22 totals the output values of the speakers transmitted from the respective controllers 42, and compares the total value with a preset output threshold value. And when a total value is larger than an output threshold value, it determines with having exceeded the power transmission capability of the power transmission device 20. Here again, the output threshold value is stored in the memory of the controller 22 or the like.

  Next, a technique for adjusting the transmission power according to the power consumption of each speaker 50 will be described.

<Example of power adjustment processing>
FIG. 5 is a flowchart illustrating an example of power adjustment processing by the wireless power supply system 10 of FIG. This power adjustment process is a process for adjusting the shortage of transmitted power by adjusting the power transmitted to each speaker 50 when the transmitted power of the power transmitter 20 is insufficient.

  First, the controller 42 of the power receiver 40 in FIG. 2 transmits the power consumption value of the speaker 50 to the controller 22 of the power transmitter 20 in FIG. 1 (step S301). The controller 22 determines whether or not the total of the power consumption values of the received speakers 50 is less than or equal to the power transmission capacity (step S302).

  When the total power consumption value of the speaker 50 is less than or equal to the power transmission capacity, the power adjustment process is terminated. If the total power consumption value of the speaker 50 is larger than the transmission capability, the transmission power is adjusted (step S303).

  In the process of step S303, the power supplied to each speaker 50 is reduced by adjusting the amount of phase shift by the phase shifter 28 and adjusting the degree of amplification by the variable gain amplifier 29. Thus, the total power consumption value of the speaker 50 is set to be equal to or less than the power transmission capacity. Further, when adjusting the transmission power, the controller 22 reduces the power supplied to each speaker 50 by the same rate according to the power consumption.

  When the adjustment is completed, each controller 42 transmits the power consumption value of the speaker 50 to the controller 22 (step S304), and executes the process of step S302. Then, when the total power consumption value of the speaker 50 is equal to or less than the power transmission capacity, the power adjustment process is ended.

  As described above, it is possible to avoid power supply in a state where the power transmission capacity is insufficient. Thereby, the operation of the speaker 50 can be stabilized.

<Specific examples of wireless power supply systems>
Next, a specific application example of the wireless power feeding system 10 will be described.

  FIG. 6 is an explanatory diagram showing an example when the wireless power feeding system 10 of FIG. 1 is applied to an electronic device.

  As described above, the power transmitter 20 included in the wireless power feeding system 10 is assumed to be installed at, for example, a ceiling or a high position close to the ceiling. In FIG. 6, the example which provided the power transmission device 20 in the lighting fixture 60 installed in a ceiling is shown.

  As shown in FIG. 6, the lighting fixture 60 is, for example, a round ceiling light. A circular LED (Light Emitting Diode) fluorescent lamp 61 is provided in the ceiling light. The LED fluorescent lamp 61 is an illumination unit. Inside the LED fluorescent lamp 61, a power transmitter 20 is provided as shown in FIG.

  FIG. 7 is an explanatory diagram showing an example of the configuration of the LED fluorescent lamp 61 included in the lighting fixture 60 of FIG. FIG. 7 shows the internal configuration of the LED fluorescent lamp 61.

  In FIG. 7, a plate-like substrate 64 extending in the circumferential direction of the LED fluorescent lamp 61 is provided at the center of the LED fluorescent lamp 61. The substrate 64 is made of, for example, PCB (Poly Chlorinated Biphenyl).

  On the main surface of the substrate 64, an LED 63 serving as an illumination unit is placed. On the back surface of the substrate 64, the power transmitter 20 is mounted. Further, the plurality of antennas 26 of FIG. 1 included in the power transmitter 20 are arranged, for example, in an array at intervals on the back surface of the substrate 64.

  In the above configuration, the LED fluorescent lamp is on the floor side and the plurality of antennas 26 are on the ceiling side, but the LED fluorescent lamp may be an indirect illumination type with the ceiling side and the plurality of antennas 26 on the lower side. Alternatively, in the lighting fixture 60 shown in FIG. 6, areas other than the LED fluorescent lamps 61 may be arranged at intervals in an array by the plurality of antennas 26 of the power transmitter 20.

  The installation position of the above power transmitter 20 is not limited to these, and may be provided in the lighting fixture 60.

  The power receiver 40 is formed in a sheet shape, and a power receiving antenna 44 is provided on the upper surface of the sheet-shaped power receiver 40. The sheet-shaped power receiver 40 is mounted on the upper surface of the speaker 50, for example. Placed. Alternatively, it may be provided inside the speaker 50. In that case, the power feeding efficiency can be further improved by providing the power receiving antenna 44 on the upper portion of the speaker 50 so as to approach the power transmitter 20.

  As described above, since the power transmitter 20 can be installed on the ceiling, a decrease in power transmission efficiency due to an obstacle or the like can be reduced. Moreover, since the power transmitter 20 is installed only by attaching the lighting fixture 60, the installation work of the power transmitter 20 etc. can be made unnecessary. Thereby, the power transmission cost 20 can be easily attached while reducing the attachment cost.

(Embodiment 2)
<Example configuration of lighting equipment>
In FIG. 7 of the first embodiment, the configuration in which the power transmitter 20 is provided inside the LED fluorescent lamp 61 has been described. In the second embodiment, another configuration example of the lighting fixture will be described.

  FIG. 8A is an explanatory diagram illustrating a specific example of the lighting fixture 70 according to the second embodiment. FIG. 8A shows a cross section of the luminaire 70.

  8A includes, for example, two straight tube LED fluorescent lamps 71 and a plurality of microwave reflectors 31. Inside the LED fluorescent lamp 71, the power transmitter 20 is provided. The microwave reflecting plate 31 is made of, for example, a plate-like metal, and is attached to the ceiling surface in an array shape.

  These microwave reflectors 31 reflect the illumination light of the LED fluorescent lamp 71 together with the reflector for illumination 38 and reflect the microwave transmitted from the power transmitter 20. Further, a phase adjusting unit 32 that adjusts the phase of the microwave is connected to the microwave reflecting plate 31.

  A plate-like substrate 72 extending in the longitudinal direction of the LED fluorescent lamp 71 is provided at the center of the LED fluorescent lamp 71. The substrate 72 is made of, for example, PCB, and a plurality of LEDs 73 serving as an illumination unit are mounted on the main surface thereof, and the power transmitter 20 is mounted on the back surface of the substrate 72. Further, the plurality of antennas 26 in FIG. 1 included in the power transmitter 20 are arranged at intervals on the back surface of the substrate 72.

  The phase adjustment unit 32 adjusts the phase of the microwave transmitted from the power transmitter 20 by changing the capacitance value of each microwave reflection plate 31, for example. Control of this adjustment is performed by the controller 22 of the power transmitter 20, for example.

  In this case, the phase shifter 28 is unnecessary in the power transmitter 20 of FIG. 1 may be an amplifier whose gain cannot be adjusted without using the variable gain amplifier 29. In that case, the microwave is adjusted only by the phase. Here, the power transmitter 20 and the plurality of antennas 26 are not necessarily arranged on the back surface of the substrate 72, and the position is not limited as long as the microwave can be sent to the microwave reflection plate.

  The phase adjustment unit 32 includes a plurality of switches 33 and a plurality of capacitive elements 34. The switch 33 and the capacitive element 34 are respectively connected in series between the microwave reflection plate 31 and the reference potential VSS. In the figure, when the reference potential VSS is connected to the grounded reflector for illumination 38, the capacitance value between the microwave reflector 31 and the reflector for illumination 38 having the ground potential changes.

  The controller 22 performs on / off control of the switch 33 by outputting an adjustment signal to a control terminal (not shown) of the switch 33. Thereby, the capacitance value of each microwave reflecting plate 31 changes, and the microwave phase shift amount can be adjusted by the microwave reflecting plate 31.

  FIG. 8B is a diagram showing an example of the overall arrangement when the lighting fixture 70 is viewed from the floor direction to the ceiling direction.

  In FIG. 8B, square microwave reflectors 31 each having a size of about 2 cm to 5 cm are arranged at regular intervals at a distance of several millimeters below the reflector for illumination 38, and further below that The LED fluorescent lamp 71 is arranged at a distance of several mm.

  The LED fluorescent lamp 71 is supplied with AC 100V power through a socket 81. As the socket 81, a conventional fluorescent lamp socket can be used as it is.

  As described above, since the microwave can be reflected using the microwave reflector 31 having a large area, the power density during power transmission can be lowered, and a person approaches the ceiling side where the power density is relatively high. There is nothing. As a result, the influence on the human body can be reduced.

  Moreover, since the power transmitter 20 can be installed on the ceiling simply by attaching the lighting fixture 70, a decrease in power transmission efficiency due to an obstacle or the like can be reduced. Further, the installation work of the power transmitter 20 and the power supply work can be made unnecessary.

(Embodiment 3)
<Overview>
In the first embodiment, the example in which the phase of the microwave is adjusted by the phase shifter 28 in FIG. 1 has been described. In the third embodiment, a technique for adjusting the phase by the antenna 26 will be described.

<Configuration example and operation of wireless power supply system>
FIG. 9 is an explanatory diagram showing an example of the configuration of the wireless power feeding system 10 according to the third embodiment.

  The wireless power feeding system 10 of FIG. 9 is different from the wireless power feeding system 10 of FIG. 1 of the first embodiment in that a phase adjustment unit 35 is provided instead of the phase shifter 28.

  The phase adjustment unit 35 is configured such that a phase shift circuit 65 is inserted between each transceiver 23 and the antenna 26. The phase shift circuit 65 includes two 0 ° phase shift microstrip lines 66 and 45 ° phase shift. It comprises a microstrip line 67, a 90 ° phase-shifting microstrip line 68, and four switches 69.

  This phase shift circuit 65 utilizes the fact that a phase difference is generated due to the transmission line length of each strip line being different. A 0 ° phase shift microstrip line 66 and a 45 ° phase shift microstrip line 67 are provided. The switch 69 can be selected, and similarly, the 0 ° phase-shifting microstrip line 66 and the 90 ° phase-shifting microstrip line 68 can also be selected.

  For this reason, by selecting a path through which the transmission / reception signal passes by the switch 69, the phase difference can be switched between four phases of 0 °, 45 °, 90 °, and 135 ° in the circuit shown in FIG. The switch 69 performs transmission line switching control based on the adjustment signal output from the controller 22.

  As described above, it is possible to change the phase of the antenna by changing the line length in addition to the technique for changing the capacitance value added to the antenna 26. Although the above-described technology makes the circuit complicated, it is possible to reduce the loss due to the impedance matching shift at the time of phase shift as compared with the case where the capacitance value of the antenna is changed.

  Here, the phase shift amount is adjusted by adding a phase shift circuit 65 between the antenna 26 and the transceiver 23. However, the phase shift amount may be adjusted by changing the length of the antenna 26, for example. Good. In this case, the phase adjustment unit 35 is provided with an antenna and a switch (not shown) instead of the phase shift circuit 65.

  One end of the switch is connected to each antenna 26. The other end of the switch is connected to an antenna included in the phase adjustment unit 35. When the switch is turned on by the adjustment signal from the controller 22, the antenna 26 is connected to the antenna included in the phase adjustment unit 35. This changes the equivalent antenna length, and as a result, the amount of microwave phase shift is adjusted.

  Also by the above, the power transmission efficiency in the wireless power feeding system 10 can be improved.

(Embodiment 4)
<Overview>
In the fourth embodiment, a technique will be described in which the power receiver 40 supplements the insufficient power when the received power is insufficient and supplies it to the electronic circuit of the speaker.

<Example configuration and operation of power receiver>
FIG. 10 is an explanatory diagram illustrating an example of a configuration of the power receiver 40 included in the wireless power feeding system according to the fourth embodiment.

  The power receiver 40 of FIG. 10 is different from the power receiver of FIG. 2 of the first embodiment in that a rechargeable battery 46 is newly provided. The rechargeable battery 46 as a charging unit is formed of a secondary battery such as a lithium ion battery. Other configurations are the same as those in FIG.

  A rectifier 43 is connected to the rechargeable battery 46, and the DC voltage generated by the rectifier 43 is charged. The rechargeable battery 46 may be charged, for example, when a speaker is not used, or extra power may be charged to the rechargeable battery 46 while using the speaker.

  The rechargeable battery 46 supplies the electric power stored in the rechargeable battery 46 to the electronic circuit when the transmitted power from the power transmitter 20 is insufficient. Alternatively, even when power is not supplied from the power transmitter 20 of FIG. 1, the power of the rechargeable battery 46 can be supplied to the electronic circuit to operate the speaker 50 of FIG.

  Thereby, even when the transmitted power from the power transmitter 20 is insufficient, the electronic circuit can be operated stably.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  For example, the wireless power supply system in the first to third embodiments supplies power to an electronic circuit provided in a speaker. However, power supply is not limited to this, for example, a smartphone or a PDA (Personal Digital Assistant). The present invention can be applied to various devices such as portable devices such as televisions, electronic devices such as televisions and personal computers, and home appliances such as refrigerators.

(Embodiment 5)
<Overview>
In the fifth embodiment, a wireless power feeding system when the charger 40 is applied to a mobile terminal such as a smartphone will be described.

<Example configuration and operation of power receiver>
FIG. 11 is an explanatory diagram illustrating an example of a configuration of the power receiver 40 included in the wireless power feeding system according to the fifth embodiment.

  As shown in FIG. 11, the power receiver 40 includes a notebook-type mobile terminal case 91, a power receiving antenna element 92, a communication unit 93, a beacon 94, a magnetic field coupling power receiving coil 95, and a mobile terminal 96 such as a smartphone. .

  The portable terminal 96 is charged by wireless charging by the charging stand 97. The portable terminal is equipped with a notebook-type portable terminal case 91 that can cover the screen with a cover. When a new power receiver 40 enters the communication range of the power transmitter 20 and power supply to the power receiver 40 is required by data communication, initial setting is performed by transmitting a beacon from the power receiver 40, and receiving is performed. Power transmission to the electric device 40 is possible.

  The power receiving antenna elements 92 are regularly arranged on the upper surface of the notebook-type portable terminal case 91, and the microwave transmission power from the luminaire 60 is efficiently obtained by forming a planar array antenna in the microwave band. It is configured to receive power well.

  In addition, for initial setting with the luminaire 60, a beacon signal is transmitted by a beacon 94 mounted on a notebook type portable terminal case 91. The control during charging is configured to use the communication unit 93. Since these are also mounted on the mobile terminal 96, beacon signals may be transmitted and communicated from the mobile terminal 96.

  The power received by the notebook type portable terminal case 91 is supplied by being connected to the portable terminal 96 through a connector (not shown).

  Further, a magnetically coupled power receiving coil 95 using the kHz band or MHz is mounted on the lower surface of the notebook type portable terminal case 91, in other words, on the back side of the portable terminal 96, and the charging stand 97 for charging the portable terminal 96 is provided. Non-contact charging is also possible by magnetically coupling with the magnetic field coupling power transmission coil 98. The communication unit 99 of the charging stand 97 and the communication unit 93 of the notebook type portable terminal case 91 communicate to perform charging control.

  In the above configuration, since the portable terminal 96 is placed with the screen facing upward, it is difficult to mount the power receiving antenna on the portable terminal by microwave power feeding from the ceiling. For this reason, by mounting the power receiving antenna element 92 for receiving microwaves on the top cover of the notebook type portable terminal case 91, it becomes possible to efficiently charge the portable terminal wirelessly.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  In addition, each of the above-described configurations may be configured so that a part or all of them are configured by hardware or executed by executing a program by a processor. Further, the control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

DESCRIPTION OF SYMBOLS 10 Wireless power supply system 20 Power transmitter 21 Communication part 22 Controller 23 Transceiver 24 Antenna array 25 Oscillator 26 Antenna 27 Amplitude phase comparator 28 Phase shifter 29 Variable gain amplifier 30 Switch part 31 Microwave reflector 32 Phase adjustment part 33 Switch 34 Capacity Element 35 Phase adjustment unit 36 Switch 37 Capacitor 38 Lighting reflector 40 Power receiver 41 Communication unit 42 Controller 43 Rectifier 44 Power receiving antenna 45 Beacon 46 Rechargeable battery 50 Speaker 60 Lighting fixture 61 LED fluorescent lamp 63 LED
64 Substrate 65 Phase shift circuit 66 0 ° phase shift microstrip line 67 45 ° phase shift microstrip line 68 90 ° phase shift microstrip line 69 Switch 70 Lighting fixture 71 LED fluorescent lamp 72 Substrate 73 LED
81 Socket 91 Notebook-type mobile terminal case 92 Power receiving antenna element 93 Communication unit 94 Beacon 95 Magnetically coupled receiving coil 96 Portable terminal 97 Charging stand 98 Magnetically coupled power transmitting coil 99 Communication unit

Claims (17)

A power transmission device that transmits microwaves to a power receiving device that supplies power to an electronic device,
A plurality of power transmission units that transmit the microwaves to the power receiving device;
A control unit for controlling the power transmission unit;
Have
The plurality of power transmission units are
An antenna for receiving the beacon signal transmitted from the microwave transmission and the power receiving device;
A microwave output unit that adjusts the phase of the microwave to be transmitted to the power receiving device based on a phase control signal and adjusts and outputs the amplification degree of the microwave based on an amplification control signal;
Each with
The control unit generates the phase control signal based on a phase difference between a reference signal and the beacon signal, and generates the amplification control signal based on an amplitude difference between the reference signal and the beacon signal. . The power transmission device according to claim 1,
The microwave output unit is
A signal detector for detecting an amplitude difference and a phase difference between the beacon signal received by the antenna and the reference signal;
A phase adjustment unit that adjusts a phase of the microwave to be transmitted to the power receiving device based on the phase control signal;
Based on the amplification control signal, a gain adjustment amplification unit that adjusts the degree of amplification of the microwave transmitted to the power receiving device;
A power transmission device. The power transmission device according to claim 1 or 2,
The control unit calculates the sum of the received power transmitted from the power receiving apparatus and determines whether the sum of the received power is greater than a preset expected power value, and the sum of the received power is the If it is less than or equal to the expected power value, the phase shift amount of the microwave or the phase control signal or the amplification control signal is generated so that the total received power is greater than the expected power value or A power transmission device that adjusts an amplification degree of the microwave. The power transmission device according to claim 1 or 2,
The control unit calculates a total value of power consumption of the electronic device transmitted from the power receiving device, determines whether the total value of power consumption is less than or equal to a power transmission capability of the power transmission device, and the consumption A power transmission device that transmits an operation stop request signal for stopping the operation of an electronic device having a low priority when it is determined that a total value of power exceeds the power transmission capability. The power transmission device according to claim 1,
The control unit determines whether or not a total value of power consumption of the electronic device transmitted from the power receiving device is less than or equal to a power transmission capability of the power transmission device, and the total value of power consumption exceeds the power transmission capability. So that the total value of the power consumption is less than or equal to the power transmission capacity when it is determined that the phase control signal or the amplification control signal is generated and the phase shift amount of the microwave or the A power transmission device that adjusts the amplification level of microwaves. In the power transmission device according to any one of claims 1 to 5,
The power transmission device is a power transmission device provided in an illumination unit included in a lighting fixture. The power transmission device according to claim 6, wherein
A reflector that reflects light emitted from the illumination unit;
A phase adjuster for adjusting the phase of the microwave by the reflector;
Have
The reflector reflects the microwave transmitted from the power transmission unit and transmits it to the power receiving device,
The phase adjustment unit is a power transmission device that adjusts a phase of the microwave reflected on the reflection plate based on the phase control signal output from the control unit. The power transmission device according to claim 7, wherein
The phase adjustment unit adjusts the phase of the microwave by changing a capacitance value or a length of the reflector. A power transmission device that transmits microwaves to a power receiving device that supplies power to an electronic device,
A plurality of power transmission units that transmit the microwaves to the power receiving device;
A control unit for controlling the power transmission unit;
A plurality of reflecting plates that reflect the microwaves transmitted from the power transmission unit and transmit power to the power receiving device;
Have
The plurality of power transmission units are
An antenna for receiving the beacon signal transmitted from the microwave transmission and the power receiving device;
A microwave output unit for amplifying and outputting the microwave;
Based on a phase control signal output from the control unit, a phase adjustment unit that adjusts the phase of the microwave reflected by the reflector, and
Each with
The control unit is a power transmission device that generates the phase control signal based on a phase difference between a reference signal and the beacon signal. The power transmission device according to claim 9, wherein
The microwave output unit is
A signal detector for detecting a phase difference between the beacon signal received by the antenna and a reference signal;
Based on the phase control signal, a phase adjustment unit that adjusts the phase of the microwave reflected on the reflector;
A power transmission device. The power transmission device according to claim 10, wherein
The microwave output unit includes a gain adjustment amplification unit that adjusts an amplification degree of the microwave transmitted to the power receiving device based on an amplification control signal;
The signal detection unit detects an amplitude difference between the beacon signal received by the antenna and the reference signal,
The control unit is a power transmission device that generates the amplification control signal based on the amplitude difference detected by the signal detection unit. The power transmission device according to any one of claims 9 to 11,
The power transmission device, wherein the phase adjustment unit adjusts a phase of the microwave reflected by the reflection plate by changing a capacitance value or a length of the reflection plate. The power transmission device according to any one of claims 9 to 12,
The power transmission device is provided in a lighting fixture,
The reflection plate is a power transmission device that reflects light from an illumination unit included in the lighting fixture. A power receiving device that receives a microwave transmitted from a power transmission device, converts the microwave into a DC voltage, and supplies power to an electronic device,
A beacon unit that transmits a beacon signal to the power transmission device;
A rectifier that rectifies the received microwave and converts it to a DC voltage;
A control communication unit that generates power reception information and transmits the power reception information to the power transmission device;
Have
The control communication unit calculates received power based on the DC voltage converted by the rectifying unit, and transmits the calculated received power to the power transmission device as the power reception information. The power receiving device according to claim 14,
The control communication unit is a power reception device that transmits power consumption of an electronic device to which the power reception device supplies power as the power reception information to the power transmission device. The power receiving device according to claim 14 or 15,
The power receiving device, wherein the control communication unit stops power supply to the electronic device when receiving an operation stop request signal for stopping the operation of the low priority electronic device from the power transmitting device. The power receiving device according to any one of claims 14 to 16, wherein
A power receiving device including a charging unit that charges a DC voltage generated by the rectifying unit.

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