WO2024261981A1 - Power transmission device and power transmission system - Google Patents

Abstract

A power transmission device (100) can transmit power to an object (50) in a non-contact manner. The power transmission device (100) is provided with a signal source (110), a Rotman lens (151), a switching device (120), and an array antenna (153). The Rotman lens (151) has a plurality of input ports and a plurality of output ports. The switching device (120) supplies the high-frequency power output from the signal source (110) to any input port of the plurality of input ports of the Rotman lens (151). The array antenna (153) radiates signals from the plurality of output ports in the Rotman lens (151). The array antenna (153) includes a plurality of antenna arrays (ANT 1 to ANT 6) provided corresponding to the plurality of output ports, respectively. Each of the plurality of antenna arrays (ANT 1 to ANT 6) has a plurality of radiation elements (160) arranged apart from each other in a first direction. For each of the plurality of radiation elements (160) of each antenna array, the phase of the radiated signal is set by the line length from the output port corresponding to the antenna array. In the antenna array, a line length corresponding to each radiation element is set so that the phase of a signal radiated from a radiation element arranged in a center part in the first direction is delayed more than a phase of a signal radiated from a radiation element arranged at an end part in the first direction.

Description

Power transmission device and power transmission system

This disclosure relates to a power transmission device and a power transmission system, and more specifically to contactless power transmission using an array antenna.

　Development of a phased array antenna that radiates a signal (radio waves) using multiple radiating elements arranged on a flat substrate is underway. In a phased array antenna, as shown in JP 2022-191769 A (Patent Document 1) or WO 2018/105303 A (Patent Document 2), beamforming is possible, adjusting the direction of the beam radiated from the array antenna by adjusting the phase of the high-frequency signal supplied to each arranged radiating element.

In JP 2022-191769 A (Patent Document 1), a phase shifter is provided in the path from the power supply circuit to the radiating element to adjust the phase of the high-frequency signal supplied to the radiating element. However, when performing beamforming, a phase shifter is required for each radiating element or for each predetermined group of radiating elements. Because phase shifters are relatively expensive, increasing the number of phase shifters can increase the size of the device and the cost of the device.

In order to solve these problems, a technology has been developed to adjust the phase using a Rotman lens, such as the antenna device disclosed in International Publication WO 2018/105303 (Patent Document 2). A Rotman lens has a configuration in which a planar pattern having multiple input ports, multiple output ports connected to radiating elements, and curved surfaces arranged between the input ports and the output ports is formed on a substrate, and the time delay amount (i.e., phase) between the multiple output ports can be changed by switching the input port that supplies the high-frequency signal.

JP 2022-191769 A International Publication No. WO 2018/105303

"Wirelessly charging smartphones using 5G communication networks - Development of a new millimeter wave wireless power supply system", fabcross for Engineer, https://engineer.fabcross.jp/archeive/210414_wirelessly-power.html (Published on May 25, 2021)

"Wireless charging of smartphones using 5G communication networks - Development of a new millimeter wave wireless power supply system" (Non-Patent Document 1) discloses a power supply system that applies the antenna device described above and supplies power contactlessly using a Rotman lens and a phased array antenna. In such a contactless power supply system, it is necessary to improve the power transmission efficiency in order to reduce power consumption on the power transmitting device side and shorten the charging time on the power receiving device side.

The present disclosure has been made to solve these problems, and its purpose is to improve the power transmission efficiency in a power transmission device that supplies power contactlessly using a phased array antenna.

The power transmission device according to the present disclosure transmits power to an object in a non-contact manner. The power transmission device includes a signal source, a Rotman lens, a switching device, and an array antenna. The Rotman lens has multiple input ports and multiple output ports. The switching device supplies high-frequency power output from the signal source to one of the multiple input ports of the Rotman lens. The array antenna radiates signals from the multiple output ports of the Rotman lens. The array antenna includes multiple antenna rows provided corresponding to the multiple output ports. Each of the multiple antenna rows has multiple radiating elements arranged at a distance in a first direction. For each of the multiple radiating elements of each antenna row, the phase of the radiated signal is set by the line length from the output port corresponding to the antenna row. In the antenna row, the line length corresponding to each radiating element is set so that the phase of the signal radiated from the radiating element arranged at the end in the first direction leads relatively to the phase of the signal radiated from the radiating element arranged in the center in the first direction.

A power transmission system according to another aspect of the present disclosure transmits power contactlessly to a moving object. The power transmission system includes a detection device for detecting the object, a power transmission device for transmitting power to the object, and a control device for controlling the power transmission device. The power transmission device includes a signal source, a Rotman lens, a switching device, and an array antenna. The Rotman lens has multiple input ports and multiple output ports. The switching device supplies high-frequency power output from the signal source to one of the multiple input ports of the Rotman lens. The array antenna radiates signals from the multiple output ports in the Rotman lens. The array antenna includes multiple antenna arrays respectively provided corresponding to the multiple output ports. Each of the multiple antenna arrays has multiple radiating elements arranged at a distance in a first direction. For each of the multiple radiating elements of each antenna array, the phase of the radiated signal is set by the line length from the output port corresponding to the antenna array. In the antenna array, the line length corresponding to each radiating element is set so that the phase of the signal radiated from the radiating element arranged at the end in the first direction leads the phase of the signal radiated from the radiating element arranged at the center in the first direction. The control device controls the switching device according to the position of the object detected by the detection device to change the direction of the signal radiated from the power transmission device.

In the power transmission device and power transmission system disclosed herein, for multiple radiating elements arranged one-dimensionally in a first direction in each antenna row of an array antenna, the line length corresponding to each radiating element is set so that the phase of the high-frequency signal radiated from the radiating element at the end of the antenna row is relatively ahead of the phase of the high-frequency signal radiated from the radiating element at the center of the antenna row. By providing a phase difference in the high-frequency signal radiated from each radiating element, directionality is created in the beam direction of the composite wave of all the radiating elements, and the signal radiated from the entire antenna row can be concentrated in a specified area. Therefore, in a power transmission device that supplies power contactlessly using a phased array antenna, it is possible to improve the power transmission efficiency.

1 is an overall schematic diagram of a power transmission system to which a power transmission device according to an embodiment is applied; FIG. 2 is a functional block diagram of the control device of FIG. 1 . FIG. 2 is a diagram illustrating a detailed configuration of the power transmitting device of FIG. 1 . 10A and 10B are diagrams for explaining a phase adjustment technique for each radiating element. 1 is a diagram for explaining the direction of a beam radiated from an array antenna. FIG. FIG. 1 is a diagram showing simulation results of the signal strength radiated from an array antenna. FIG. 2 shows the simulation results of the signal strength radiated from the array antenna. FIG. 3 shows the simulation results of the signal strength radiated from the array antenna. 13A and 13B are diagrams illustrating an example of measurement of signal strength when the input to the Rotman lens is switched.

Below, the embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the same or corresponding parts in the drawings will be given the same reference numerals and their description will not be repeated.

(Outline of the power transmission system)
1 is an overall schematic diagram of a power transmission system 10 to which a power transmission device 100 according to the present embodiment is applied. The power transmission system 10 is a system for contactlessly transmitting power to a movable object 50. The object 50 is, for example, a transport vehicle that transports parts or the like in a factory. The object 50 has a power receiving device 51, which receives power supplied from the power transmission system 10 and uses the received power to charge a battery (not shown) mounted on the object 50 or to operate various electrically-powered devices.

Referring to FIG. 1, the power transmission system 10 includes, in addition to the power transmission device 100, a control device 300, and a number of sensors S1 to S3 arranged on the movement path of the target object 50. The power transmission device 100 includes a signal source 110, a switching device 120, and an antenna device 150 in which a number of radiating elements 160 are arranged. The power transmission device 100 is controlled by the control device 300, and radiates high-frequency power generated by the signal source from the antenna device 150 to supply power to the target object 50 in a non-contact manner. At this time, the direction of the beam radiated from the antenna device 150 can be changed by switching the input position of the high-frequency power to the antenna device 150 using the switching device 120. The detailed configuration of the antenna device 150 will be described later with reference to FIG. 3 and FIG. 4.

In the example of FIG. 1, the object 50 is configured to be able to move, for example, between three stations P1 to P3 on the movement route RD, stopping at each station to load and unload parts. In this case, when the object 50 is stopped at each station, the power transmission device 100 switches the beam direction to the direction of the station where the object 50 is stopped. When the object 50 is stopped at station P1, the beam direction is switched to beam direction BM1. Similarly, when the object 50 is stopped at station P2, the beam direction is switched to beam direction BM2, and when the object 50 is stopped at station P3, the beam direction is switched to beam direction BM3.

Sensors S1 to S3 are disposed at stations P1 to P3, respectively. Sensors S1 to S3 detect whether or not the object 50 is stopped at the corresponding station. Sensor S1 may be, for example, a mechanical limit switch, or a non-contact magnetic sensor or optical sensor. Alternatively, sensors S1 to S3 may be a reader for an identifier such as an RFID or barcode affixed to the object 50. Detection signals DP1 to DP3 detected by sensors S1 to S3, respectively, are transmitted to the control device 300.

In addition, to detect the position of the target object 50, an imaging device (camera) 250 may be used instead of or in addition to the above-mentioned sensors S1 to S3. Image data IMG captured by the imaging device 250 is transmitted to the control device 300.

The control device 300 is, for example, a computer system, and includes a CPU (Central Processing Unit) 310, memory 320, and an input/output interface (I/F) 330, all of which are communicatively connected to a common bus. The memory 320 includes a ROM (Read Only Memory) and a RAM (Random Access Memory) made of volatile or non-volatile semiconductor memory, and/or a large-capacity storage device such as a HDD (Hard Disc Drive) and an SSD (Solid State Drive).

The CPU 310 receives the detection signals DP1-DP3 of the sensors S1-S3 and/or the image data IMG captured by the imaging device 250 via the I/F 330. The CPU 310 generates control signals CON1, CON2 for controlling the signal source 110 and the switching device 120 of the power transmission device 100, respectively, by executing a program stored in the memory 320 based on the received data. The generated control signals CON1, CON2 are output to the signal source 110 and the switching device 120 via the I/F 330. Note that the control device 300 may be constructed with a hardware circuit instead of the software processing described above. Alternatively, the control device 300 may be a combination of a hardware circuit and software processing.

2 is a functional block diagram of the control device 300 in FIG. 1. The control device 300 includes an input unit 301, a position detection unit 302, a signal control unit 304, and a switching control unit 305. If the power transmission system 10 includes an imaging device 250, an image analysis unit 303 is further included in addition to the above configuration.

In terms of hardware, the input unit 301 corresponds to the I/F 330 in FIG. 1. The input unit 301 acquires the detection signals DP1 to DP3 of the sensors S1 to S3, and, if an imaging device 250 is provided, image data IMG from the imaging device 250. The input unit 301 outputs the detection signals DP1 to DP3 to the position detection unit 302, and outputs the image data IMG to the image analysis unit 303.

The image analysis unit 303 determines the position of the object 50 by analyzing the acquired image data IMG, and outputs the determination result to the position detection unit 302. The position detection unit 302 detects at which station the object 50 is stopped based on the acquired detection signals DP1 to DP3 and/or the determination result by the image analysis unit 303. The position detection unit 302 outputs information on the detected stopping position of the object 50 to the signal control unit 304 and the switching control unit 305.

The signal control unit 304 generates a control signal CON1 for controlling the signal source 110 based on information on the stopping position of the object 50, and outputs the signal to the signal source 110. For example, when the distance from the power transmission device 100 to each station is different, the signal control unit 304 changes the output power of the high-frequency signal output from the signal source 110 depending on the station. Alternatively, when multiple objects 50 are targets for receiving power, if the receiving frequency differs for each moving body, the signal control unit 304 may adjust the frequency of the high-frequency signal depending on the object 50 to which power is to be transmitted.

The switching control unit 305 changes the input position of the high-frequency signal to the antenna device 150 by switching the switching device 120 based on information about the stopping position of the object 50. This causes the direction of the beam emitted from the antenna device 150 to move in the direction of the station where the object 50 is stopped.

By performing the above-described control in the control device 300, even if the stopping position of the object 50 on the movement route RD changes, it is possible to appropriately transmit power from the power transmission device 100 to the stopping position of the object 50.

Note that power transmission from the power transmission device 100 may be performed not only when the target object 50 is stopped at the station, but also while the target object 50 is moving on the moving route RD. In other words, the direction of the beam radiated from the antenna device 150 is set to the direction determined from the position of the sensor that detects the target object 50.

Specifically, the position of the object 50 on the movement path RD may be estimated from the time when it passed the sensor and the movement speed of the object 50, and the beam direction may be set based on the estimated position to transmit power. Alternatively, if the movement speed of the object 50 is fixed, power may be transmitted in a predetermined beam direction after a predetermined time has elapsed since the time when it passed the sensor.

Also, when the object 50 moves according to a position control signal (transport command), the position of the object 50 may be determined from the transport command for movement and the beam direction may be switched without using detection devices such as sensors and imaging devices. When the movement control of the object 50 is performed by the control device 300, the control device 300 determines the position of the object 50 from the transport command calculated inside the control device 300. On the other hand, when the movement control of the object 50 is performed by a control device other than the control device 300, or when the position of the object 50 is autonomously controlled by a control device mounted on the object 50, the control device 300 receives a transport command for the object 50 from these other control devices and determines the position of the object 50 from the transport command.

FIG. 3 is a diagram showing a detailed configuration of the power transmission device 100 in FIG. 1. As described in FIG. 1, the power transmission device 100 includes a signal source 110, a switching device 120, and an antenna device 150. The antenna device 150 includes a Rotman lens 151, an amplifier 152, and an array antenna 153.

The signal source 110 includes a mixer and a local oscillator, neither of which are shown, and upconverts the signal to be transmitted to generate a high-frequency signal. In the power transmission device 100 of this embodiment, the frequency of the high-frequency signal radiated from the antenna device 150 is, for example, a microwave band frequency of 900 MHz to 30 GHz. The power transmitted by the power transmission device 100 varies depending on the frequency used, but is approximately 1 to 30 W.

The switching device 120 is a so-called SPNT type switch that includes an input terminal T0 and output terminals T1 to T5. The switching device 120 receives a high-frequency signal from the signal source 110 at the input terminal T0, and supplies the signal to one of the multiple output terminals T1 to T5. The number of output terminals is determined according to the number of input ports of the Rotman lens 151.

The Rotman lens 151 has a configuration in which a planar pattern having multiple input ports, multiple output ports, and a main body 1512 arranged between these input and output ports is formed on a flat dielectric substrate 1511. The main body 1512 has a shape that is approximately elliptical with protrusions formed around the periphery that connect to each port. In the example of Figure 3, five input ports and six output ports are set. The input ports are connected to input terminals T11 to T15, respectively. The output ports are connected to output terminals T21 to T26, respectively, via corresponding wiring sections PS1 to PS6.

The Rotman lens 151 determines the phase between signals output from the output ports according to the transmission distance from one input port to each output port. The Rotman lens 151 in FIG. 3 has a shape that is linearly symmetrical with the direction from the input terminal to the output terminal (the X-axis direction in FIG. 3) as the axis of symmetry. The line lengths of the wiring sections PS1 to PS6 are set so that when a high-frequency signal is input to the input terminal T13, which is located on this axis of symmetry, the signals output from the output terminals T21 to T26 have the same phase. Therefore, when the center input terminal T13 is selected by the switching device 120, signals of the same phase are output from the output terminals T21 to T26.

The array antenna 153 includes a plurality of radiating elements 160 and a dielectric substrate 161 on which the radiating elements 160 are arranged. The array antenna 153 in FIG. 3 is an array antenna in which 72 radiating elements 160 are arranged in a 12 x 6 two-dimensional array on the dielectric substrate 161 or on the inner layer of the dielectric substrate 161. The radiating elements 160 are grouped into six antenna arrays ANT1 to ANT6, each of which includes 12 elements arranged in the X-axis direction. The antenna arrays ANT1 to ANT6 are connected to the output terminals T21 to T26 of the Rotman lens 151, respectively, via the amplifier 152.

That is, a high-frequency signal is transmitted to each radiating element in the antenna array ANT1 from output terminal T21 of the Rotman lens 151. Similarly, a high-frequency signal is transmitted to each radiating element in the antenna arrays ANT2 to ANT6 from output terminals T22 to T26, respectively.

As described above, the phase between the signals output from the output terminals T21 to T26 changes when the switching device 120 switches the input port to which the high frequency signal is supplied in the Rotman lens 151. In other words, by switching the input port to which the high frequency signal is supplied, the phase between the signals radiated from the antenna arrays ANT1 to ANT6 can be changed, thereby enabling beamforming in the Y-axis direction in FIG. 3.

Note that amplifier 152 is not necessarily a required component, and if the desired amplification rate can be achieved by an amplifier (not shown) included in signal source 110, output terminals T21 to T26 may be directly connected to antenna arrays ANT1 to ANT6, respectively.

(Phase Adjustment Method)
Fig. 4 is a diagram for explaining the details of the phase adjustment method of each radiating element 160. In the array antenna 153 of Fig. 4, a wiring pattern (feeding wiring) for transmitting a high-frequency signal to each radiating element 160, which is arranged inside a dielectric substrate 161, is shown.

The wiring pattern corresponding to each antenna array branches out and extends from near the center of the arrangement direction of the 12 radiating elements 160 in two directions, the positive and negative directions of the X-axis, and is connected to each radiating element 160. At this time, the line length to each radiating element 160 is set so that the phase of the signal radiated from each radiating element 160 is made different. More specifically, the line length is set so that the phase of the signal radiated from the radiating element closer to both ends in the X-axis direction advances relatively to the phase of the signal radiated from the radiating element near the center in the X-axis direction.

By setting the line length between the radiating elements in each antenna array in this way, a directionality is generated in the composite wave of all the radiating elements in each antenna array. Therefore, by appropriately adjusting the phase difference for each radiating element, the phase of the signal at a specific position spaced apart in the normal direction of the dielectric substrate 161 near the center in the X-axis direction can be matched, thereby increasing the signal strength. In other words, the transmission power can be concentrated at that specific position.

Furthermore, in the array antenna 153, the line length is set so as to make the phases different between the antenna rows. More specifically, the line length is set so that the phase of the signal radiated from the antenna row near the center in the Y-axis direction advances relatively as it approaches both ends in the Y-axis direction.

By setting the line length between the antenna rows in this way, the composite wave also has directionality in the Y-axis direction. Therefore, by appropriately adjusting the phase difference between each antenna row, the phase of the signal at a specific position spaced apart in the normal direction of the dielectric substrate 161 near the center in the Y-axis direction can be matched, thereby increasing the signal strength. In other words, the transmitted power can be concentrated at that specific position.

As described above, in the array antenna 153, the beam direction of the signal radiated from each radiating element 160 can be concentrated near the center of the X-axis and Y-axis. In other words, the array antenna 153 functions as a "focusing lens" that concentrates the radiated signal at a predetermined focal point. By placing the receiving antenna at this focal position, the efficiency of power transmission from the power transmitting device 100 can be improved. The focal length of the beam is determined by the phase difference between the radiating elements in each antenna row and the phase difference between the antenna rows. Increasing the phase difference shortens the focal length, and decreasing the phase difference lengthens the focal length.

Also, as described above, by switching the input port of the Rotman lens 151, the phase of the signal between the output ports of the Rotman lens 151 can be adjusted. For example, as shown in FIG. 4, when a high-frequency signal from the signal source 110 is input to the input terminal T15 by the switching device 120, the distance (arrow AR1) from the input port corresponding to the input terminal T15 to the wiring section PS1 becomes longer than the distance (arrow AR2) from the input port to the wiring section PS6. Therefore, the phase of the signal radiated from the antenna array ANT1 is delayed relatively compared to the phase of the signal radiated from the antenna array ANT6. As a result, the beam direction of the signal radiated from the entire array antenna 153 is tilted in the positive direction of the Y axis as shown by the arrow AR3, and the specific position (i.e., the focal position) shifts in the Y axis direction.

FIG. 5 is a diagram for explaining the direction of the beam radiated from the array antenna 153 of the power transmission device 100. In FIG. 5, the left diagram (A) shows the phase difference of the high frequency signal between the radiating elements caused by the Rotman lens 151, and the center diagram (B) shows the phase difference of the high frequency signal between the radiating elements caused by the difference in the path length of the power supply wiring in the array antenna 153. And the right diagram (C) shows the total phase difference of the signal radiated by the entire power transmission device 100. Note that in FIG. 5, the phase difference is shown in shades, with the darker the color, the greater the phase delay. Also, the left diagram (A) of FIG. 5 shows the case where a high frequency signal is supplied to the input terminal T15 of the Rotman lens 151 as in FIG. 4.

As shown in the left diagram (A) of FIG. 5, when a high frequency signal is supplied to the input terminal T15 of the Rotman lens 151, the phase of the high frequency signal radiated from the antenna array ANT6 in the negative direction of the Y axis relatively advances, and the phase of the high frequency signal radiated from the antenna array ANT1 in the positive direction of the Y axis relatively delays. As a result, the beam direction of the signal radiated from the array antenna 153 tilts in the positive direction of the Y axis. Also, as shown in the middle diagram (B) of FIG. 5, depending on the setting of the path length of the power supply wiring of the array antenna 153, the phase of the signal radiated from the radiating element 160 near the center of the array antenna relatively delays, and the phase of the signal radiated from the radiating element 160 near the outer periphery of the array antenna relatively advances. As a result, the beam direction of the signal radiated from the array antenna 153 is concentrated at a focal position at a predetermined distance from the array antenna.

As a result, the power transmission device 100 as a whole is in a state where the signal phase is most delayed at the position offset in the positive direction of the Y axis from the center of the array antenna (arrow AR4). Therefore, the focal position of the beam can be moved in the positive direction of the Y axis. The amount of movement of the focal position in the Y axis direction can be controlled by switching the input position to the Rotman lens 151 using the switching device 120.

(Experimental Example)
Next, an experimental example regarding the strength of a signal transmitted from the power transmitting device 100 will be described with reference to FIGS.

Figures 6 to 8 are simulation results showing the distribution of signal strength radiated from antenna device 150. In the simulation, the principal surface of antenna device 150 was taken as the XY plane, and the normal direction of the principal surface of antenna device 150 was taken as the Z axis. Simulations were then performed on the intensity distribution in the ZX plane at the center of the Y axis direction of the antenna array (Figure 7), and the intensity distribution in the XY plane near the focal position of the beam (Figure 8). Figure 8 corresponds to the cross-sectional view at line VIII-VIII in Figure 7.

In the simulation, a high-frequency signal is input to input terminal T13 of the Rotman lens 151, and the signals output from output terminals T21 to T26 are in phase. In the distribution diagrams of Figures 6 to 8, locations with strong signal strength are shown in darker colors.

As shown in FIG. 7, in the ZX plane, the signal strength is partially strong at a specific position near the center of the antenna device 150, away from the antenna device 150 in the Z-axis direction, and the signal strength in other parts is weaker than that specific position. That is, it can be seen that the beam is concentrated near the center in the X-axis direction. Also, as shown in FIG. 8, in the XY plane, the signal strength is strong in a spot shape, and it can be seen that the beam is concentrated near the center in the Y-axis direction as well as the X-axis direction. That is, it can be seen that the antenna device 150 functions as a focusing lens. Note that, in one example, by using the configuration of this embodiment, it is possible to improve the power transmission efficiency by about 10 times compared to a case in which no phase difference is provided in the array antenna 153 and no focal beam is formed.

Figure 9 shows an example of signal strength measurement when the input to the Rotman lens 151 is switched. In the measurement in Figure 9, the near electromagnetic field is measured at a position away from the antenna device 150 by a distance corresponding to the focal position. Figure 9 shows the measurement results when high-frequency signals are supplied to the input terminals T13, T14, and T15 of the Rotman lens 151. Note that the position of zero on the horizontal axis corresponds to the center of the array antenna 153 in the X-axis direction, and the position of zero on the vertical axis corresponds to the center of the array antenna 153 in the Y-axis direction.

When a high frequency signal is supplied to input terminal T13 (left diagram), the position of the spot where the signal strength is strong is near the center. When a high frequency signal is supplied to input terminal T14 (middle diagram), the position of the spot moves slightly in the positive direction of the Y axis. When a high frequency signal is supplied to input terminal T15 (right diagram), the position of the spot moves further in the positive direction of the Y axis. In this way, it can be seen that by switching the input to the Rotman lens 151, the focal position moves in the Y axis direction.

As described above, in a power transmission device that uses an array antenna to supply power contactlessly, by using beamforming with a Rotman lens and an antenna board that functions as a focusing lens, it is possible to transmit power to different positions while concentrating the power at a specific focal position. This improves the power transmission efficiency and allows a single power transmission device to supply power to a movable object. Furthermore, by forming a focal beam, the size of the receiving antenna on the power receiving device side can be reduced.

In the above example, the power transmission system of the embodiment is described as being applied to powering a transport vehicle that transports parts and the like within a factory, but the power transmission system may also be applied to powering vehicles that run on public roads, for example. The concept of the power transmission system can also be applied to a system that transmits electricity generated by solar panels placed in space to the ground.

[Aspects]
It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

　(1) A power transmission device according to one embodiment transmits power to an object in a non-contact manner. The power transmission device includes a signal source, a Rotman lens, a switching device, and an array antenna. The Rotman lens has multiple input ports and multiple output ports. The switching device supplies high-frequency power output from the signal source to one of the multiple input ports of the Rotman lens. The array antenna radiates a signal transmitted from the multiple output ports of the Rotman lens. The array antenna includes multiple antenna rows provided corresponding to the multiple output ports. Each of the multiple antenna rows has multiple radiating elements arranged at a distance in a first direction. For each of the multiple radiating elements of each antenna row, the phase of the radiated signal is set by the line length from the output port corresponding to the antenna row. In the antenna row, the line length corresponding to each radiating element is set so that the phase of the signal radiated from the radiating element arranged at the end in the first direction leads relatively to the phase of the signal radiated from the radiating element arranged in the center in the first direction.

(2) In the power transmission device described in 1, the line length corresponding to each radiating element is set so that the phase of the signal radiated from each radiating element in each antenna row coincides at a predetermined position spaced apart in the radiation direction from the array antenna.

(3) In the power transmission device described in 2, the multiple antenna arrays are arranged in a second direction that intersects with the first direction.

(4) In the multiple antenna arrays of the power transmission device described in 3, the line length corresponding to each radiating element is set so that the phase of the signal input to the radiating element of the antenna array located at the center in the second direction lags behind the phase of the signal input to the radiating element of the antenna array located at the end in the second direction.

(5) In the power transmission device described in 4, when the input port in the switching device that supplies high-frequency power from the signal source is switched, the predetermined position shifts in the second direction.

(Section 6) A power transmission system according to another aspect transmits power to a moving object in a non-contact manner. The power transmission system includes a power transmission device that transmits power to the object, and a control device for controlling the power transmission device. The power transmission device includes a signal source, a Rotman lens, a switching device, and an array antenna. The Rotman lens has multiple input ports and multiple output ports. The switching device supplies high-frequency power output from the signal source to one of the multiple input ports of the Rotman lens. The array antenna radiates a signal transmitted from the multiple output ports in the Rotman lens. The array antenna includes multiple antenna arrays that correspond to the multiple output ports. Each of the multiple antenna arrays has multiple radiating elements that are arranged at a distance in a first direction. For each of the multiple radiating elements of each antenna array, the phase of the radiated signal is set by the line length from the output port corresponding to the antenna array. In the antenna array, the line length corresponding to each radiating element is set so that the phase of the signal radiated from the radiating element located at the end in the first direction leads the phase of the signal radiated from the radiating element located in the center in the first direction. The control device controls the switching device according to the position of the target object to change the direction of the signal radiated from the power transmission device.

(7) The power transmission system described in 6 further includes a detection device for detecting an object. The control device controls the switching device according to the position of the object detected by the detection device to change the direction of the signal emitted from the power transmission device.

(Section 8) In the power transmission system described in Section 7, the detection device includes a plurality of sensors for detecting an object. The plurality of sensors are arranged on the path of movement of the object. The control device controls the switching device so that a signal from the power transmission device is emitted in a direction determined from the position of the sensor that has detected the object among the plurality of sensors.

(Clause 9) In the power transmission system described in Clause 7, the detection device includes a camera. The control device controls the switching device so that a signal from the power transmission device is emitted in the direction of the object detected by the detection device based on the position of the object detected by the detection device.

(Article 10)
In the power transmission system described in paragraph 6, the control device controls the switching device in accordance with the position of the object determined based on a position control signal for moving the object, thereby changing the direction of the signal radiated from the power transmission device.

The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than the description of the embodiments above, and is intended to include all modifications within the meaning and scope of the claims.

10 Power transmission system, 50 Object, 51 Power receiving device, 100 Power transmission device, 110 Signal source, 120 Switching device, 150 Antenna device, 151 Rotman lens, 152 Amplifier, 153 Array antenna, 160 Radiating element, 161, 1511 Dielectric substrate, 250 Imaging device, 300 Control device, 301 Input section, 302 Position detection section, 303 Image analysis section, 304 Signal control section, 305 Switching control section, 320 Memory, 1512 Main body section, ANT1 to ANT6 Antenna array, P1 to P3 Stations, PS1 to PS6 Wiring section, RD Movement path, S1 to S3 Sensors, T0, T11 to T15 Input terminals, T1 to T5, T21 to T26 Output terminals.

Claims (10)

A power transmission device that transmits power to an object in a non-contact manner,
A signal source;
a Rotman lens having a plurality of input ports and a plurality of output ports;
a switching device for supplying high frequency power output from the signal source to any one of the plurality of input ports;
an array antenna for radiating signals transmitted from the plurality of output ports of the Rotman lens;
the array antenna includes a plurality of antenna rows provided corresponding to the plurality of output ports,
Each of the plurality of antenna arrays has a plurality of radiating elements arranged at a distance from each other in a first direction,
For each antenna array,
a phase of a signal to be radiated is set for each of the plurality of radiating elements according to a line length from an output port corresponding to the antenna array;
a power transmitting device in which the line length corresponding to each radiating element in the antenna array is set so that the phase of a signal radiated from the radiating element arranged at the end in the first direction leads relatively more than the phase of a signal radiated from the radiating element arranged in the center in the first direction. The power transmission device according to claim 1, in which the line length corresponding to each radiating element is set so that the phase of the signal radiated from each radiating element in each antenna row coincides at a predetermined position spaced apart in the radiation direction from the array antenna. The power transmission device according to claim 2, wherein the plurality of antenna arrays are arranged in a second direction that intersects with the first direction. The power transmission device according to claim 3, wherein the line length corresponding to each radiating element is set so that the phase of a signal input to a radiating element of an antenna array arranged at the center in the second direction lags behind the phase of a signal input to a radiating element of an antenna array arranged at an end in the second direction. The power transmission device according to claim 4, wherein when the input port of the switching device that supplies high-frequency power from the signal source is switched, the predetermined position shifts in the second direction. A power transmission system that transmits power to a moving object in a non-contact manner,
A power transmitting device that transmits power to the object;
A control device for controlling the power transmitting device,
The power transmitting device is
A signal source;
a Rotman lens having a plurality of input ports and a plurality of output ports;
a switching device for supplying high frequency power output from the signal source to any one of the plurality of input ports;
an array antenna for radiating signals transmitted from the plurality of output ports of the Rotman lens;
the array antenna includes a plurality of antenna rows provided corresponding to the plurality of output ports,
Each of the plurality of antenna arrays has a plurality of radiating elements arranged at a distance from each other in a first direction,
For each antenna array,
a phase of a signal to be radiated is set for each of the plurality of radiating elements according to a line length from an output port corresponding to the antenna array;
in the antenna array, a line length corresponding to each radiating element is set so that a phase of a signal radiated from a radiating element disposed at an end in the first direction leads relatively to a phase of a signal radiated from a radiating element disposed at a center in the first direction,
The control device controls the switching device in accordance with a position of the object to change a direction of a signal radiated from the power transmitting device. a detection device for detecting the object,
The power transmitting system according to claim 6 , wherein the control device controls the switching device in response to a position of the object detected by the detection device to change a direction of a signal radiated from the power transmitting device. the detection device includes a plurality of sensors for detecting the object, the plurality of sensors being disposed along a path of movement of the object;
The power transmission system according to claim 7 , wherein the control device controls the switching device so that the signal from the power transmission device is emitted in a direction determined from a position of a sensor that detects the object among the plurality of sensors. the detection device includes a camera;
The power transmission system according to claim 7 , wherein the control device controls the switching device based on the position of the object detected by the detection device so that a signal from the power transmission device is emitted in the direction of the object detected by the detection device. The power transmission system according to claim 6, wherein the control device controls the switching device in response to the position of the object determined based on a position control signal for moving the object, thereby changing the direction of the signal emitted from the power transmission device.

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